Abstract in English:ABSTRACT The potential of royal jelly production in Africanized honeybee colonies was evaluated using techniques involving two queens per colony in horizontal and vertical systems during the spring of 2019. The techniques were tested for their effect on cell acceptance (%); royal jelly production per colony (g), per harvest (g), and per position of cell bar (g) and compared with standard techniques (five and ten-frame hives) in southern Brazil. Results showed statistical significance in royal jelly production between methods. Vertical colonies produced a significantly greater amount of royal jelly per colony and per harvest (8.26 and 53.28±4.98 g) compared with single-queen colonies in ten-frame hives (4.30 and 32.76±3.57 g) and five-frame hives overlapping (2.03 and 14.45±2.48 g), but did not differ from two-queen horizontal colonies (8.09 and 46.81±4.90 g). In contrast, there was no significant difference in queen cell acceptance rate within vertical, horizontal, and ten-frame colonies. Royal jelly yield of two-queen vertical colonies increase as compared with standard colonies.
Abstract in English:ABSTRACT The objective of this study was to analyze the perceptions of professionals in relation to the importance of indicators used to assess the sustainability of Brazilian dairy cattle. A survey method was used through a questionnaire. The target audience was professionals related to dairy cattle: researchers, professors, consultants, farmers, and other professionals. The total number of respondents to the survey was 347. Cluster analysis resulted in the formation of four distinct groups: G1 (“Holistic”), participants agreed that all indicators are very important or, at least, important; G2 (“Technician”) considered the indicators important and desirable, except for some environmental indicators which were assessed as non-priority and expendable; G3 (“Socio-environmentalist”) assessed the indicators as desirable, but environmental indicators received more importance; and G4 (“Skeptic”) generally believed that indicators were non-priority and expendable. The groups showed significant differences in relation to knowledge about technical, economic, social, and environmental aspects of dairy cattle. More than 60% of professionals consider milk production per area, reproductive index, production costs, profit from the activity, milk quality, quality of life of the producer and employees, succession, protection of water courses, and soil management as very important indicators of the sustainability of dairy cattle. On the other hand, important environmental indicators such as emissions of gases and substances, energy use, nutrient balance, and land use were neglected by most respondents. These results can help select and implement policies and strategies for decision making, aiming at producing milk in a more sustainable way.
Abstract in English:ABSTRACT The experiment aimed to analyze the economic viability of using high-energy diets and the supplementation of chromium propionate or calcium salts of palm oil in the diet of ewes from the late gestation until the end of lactation. Seventy-two ewes of Santa Ines × Dorper crossbreeds were allocated to five treatments: CTL (n = 14) with 100% of NRC recommendation for metabolizable energy per kg dry matter intake (ME/kg DMI), LOW (n = 14) with 90% ME/kg DMI, HIGH (n = 15) with 110% ME/kg DMI, Cr (n = 15) HIGH diet plus chromium propionate, and FAT (n = 14) HIGH diet plus calcium salts of palm oil. Based on the performance data, a short-term analysis was performed for a module of 1000 ewes, evaluating costs, revenues, and profitability, and long-term analysis was performed by an additional cash flow of 120 months. The CTL and FAT treatments were not viable due to higher costs and lower revenues, and they also had a negative net present value (NPV) and internal rate of return (IRR). The LOW treatment, despite lower costs and positive profitability, had a negative NPV (-$872.90) and IRR (1.85%) that was below the discount rate, making it unprofitable in the long run. The HIGH and Cr treatments were considered feasible because they had lower unit costs and higher profitability, in addition to a high NPV ($64,894.11 and 104,902.05, respectively) and a higher IRR (9.03% and 13.65%, respectively) than the discount rate. The use of high-energy diets, with added chromium propionate, promoted better performance and, consequently, better economic return.
Abstract in English:ABSTRACT This study was performed to evaluate the efficiency index of cow-calf systems, based on different feed technologies commonly employed in the Rio Grande do Sul state, southern Brazil. Hence, the efficiency of 35 cow-calf herds was evaluated by Data Envelopment Analysis (DEA). Data was collected by online survey and in-depth interviews, as well as data registers from the cow-calf systems, located in 31 municipalities. The analyzed indicators included rates of mortality, pregnancy, birth, and productivity. The feed technologies evaluated were the use of cultivated pastures during winter and summer, supplementation during winter and summer, creep feeding, deferral of natural pasture, use of grazing systems, and employee's capacitation. Approximately 80% of the evaluated farms showed low-to-medium Efficiency Index (EI; up to 0.79 in a scale of 0 to 1), 13% presented high EI, and only 7% had very high EI (above 0.95). The use of cultivated pastures with the inclusion of protein supplementation and employees’ capacitation were highlighted as the main practices to increase efficiency of cow-calf systems in Rio Grande do Sul. The technologies identified as most impactful raise the EI of production systems from low to medium. Our results assist in decision-making in the use of feed technologies, pointing out a direction for the use of technologies that make breeding systems more efficient from a productive point of view.
Abstract in English:ABSTRACT This study aimed at analyzing and comparing the phenotypic characteristics of height, body length, and fleece wool fineness with the liquidity and final price sold in auctions in the city of Uruguaiana, RS, Brazil, for three consecutive years (2015 to 2017). A total of 412 one-year-old (two teeth) male sheep, of the Australian Merino (n = 50), Polwarth (n = 130), and Corriedale (n = 232) breeds were evaluated. Height and length of the animals were measured on the day of the auction with a measuring tape, and animals were grouped into small or tall and short or long categories, as defined in this study. Wool fineness was measured using an Optical-based Fibre Diameter Analyser (FDA 2000) device and classified according to official wool classification standards (the Bradford System). There was no statistical difference in the average selling price of different breeds. There was a correlation between the breed and liquidity, in which Corriedale lambs were sold more than the Polwarth lambs, as expected; however, there was no such correlation for Merino lambs. The tall Merino lambs were sold at a higher selling price (R$ 2,449.11) than the small ones (R$ 1,826.59). Polwarth lambs exhibited positive correlations among height, length, and liquidity. Long and tall Corriedale lambs had a higher selling price (R$ 1,963.40 and R$ 1,915.02) than the short (R$ 1,656.38) and small (R$ 1,698.20) ones, respectively. In the case of Corriedale lambs, there was a positive correlation between length and liquidity. Wool fineness did not influence the selling price and liquidity in the three studied breeds. Conclusively, buyers of the Polwarth and Corriedale lambs prefer tall and long animals, regardless of the fleece wool fineness; only the height (taller lambs) seems to be a relevant factor for choosing the Merino breeders.
Abstract in English:ABSTRACT The objective of this study was to characterize and understand the investment profile towards technologies for control and automation of climate control on swine farms, focused on integrated producers on the same integration system. A structured questionnaire including open, dichotomic, or multiple-choice questions was responded by 190 integrated producers classified as nursery (28,300 swines), wean-to-finish (WTF; 144,388 swines), or finishing unit (FU; 164,185 swines) farms. Data were described and categorized according to the type of integrated producer (nursery, WTF, and FU) and income history during a 24-month interval. The most predominant farmer profile was of a 44.5-year-old man, with incomplete secondary education. Furthermore, the majority of the farms had family-based labor with an average area of 43.6±65.5 ha and ~2.4 economic activities developed. Overall, a reduced labor availability was observed, although the integrated producers declared to be satisfied with the activities. Interestingly, integrated producers with a better income history declared a longer working (high = 37; average = 31; regular = 31; low = 28 min). The investment profile in automation technologies is conservative; however, potential improvements in pig performance were the most popular justification for potential investments. Furthermore, high costs, knowledge in technologies, interest rates, and quality of the available material are the limiting factors for investing in environment control. A total of 74% of the integrated producers considered the activity as economically profitable. Lastly, the uptake of environmental control technologies is strongly associated with the average income received by farmers.
Abstract in English:ABSTRACT This study determined the apparent digestibility for crude protein (ACPD) and essential aminoacids (AEAAD) of ingredients for Litopenaeus vannamei fed diets containing soy protein concentrate (SPC), corn gluten meal (CGM), poultry byproduct meal (PBM), meat and bone meal (MBM), hydrolyzed feather meal (HFM), spray-dried blood meal (DBM), tilapia byproduct meal (TBM), Brazilian marine fish meal (BFM), salmon byproduct meal (SLM), and krill meal (KRM). Digestibility was estimated using chromic oxide as a marker in a reference (REF) mixture. Shrimp of 6-8 g body weight were reared over three separate experimental stages lasting 29-30 days each. Shrimp survival exceeded 96% and was unaffected by test ingredient. The ACPD ranged from 66.7% for a diet containing DBM to 84.2% for the REF diet. Higher ACPD were observed for aquatic compared with plant and terrestrial animal byproducts. Aside from SPC (79.3%), ACPD for CGM was low at 47.5%. Among terrestrial animal byproducts, ACPD was higher for MBM compared with PBM, DBM, and HFM (71.2, 62.8, 48.6, and 45.9%, respectively). With the exception of BFM (59.7%), ACPD for all other aquatic proteins was high (KRM, 84.3%; TBM, 83.3%; SLM, 78.9%). Aquatic proteins have higher crude protein (CP) and essential aminoacid (EAA) digestibility for shrimp. Ingredients SLM, SPC, TBM, and KRM are preferable in feeds for the whiteleg shrimp since they carry a high CP and EAA content (>600 g kg−1) combined with ADC near or in excess of 80%.
Abstract in English:ABSTRACT The objective of the present study was to evaluate the effects of cooling systems by negative pressure versus directed ducts on the performance of lactating sows and their litter. The experiment was conducted in a tropical climatic region in Brazil. Ninety-four lactating sows during 26.2±1.7 days of lactation were included with their 1,236 piglets. Sows were distributed using a completely randomized block design into two treatments: a negative pressure cooling (NPC) system and a directed duct cooling (DDC) system. We adopted sow parity as blocking criterion. During the experimental period, environmental temperatures inside the farrowing rooms were 22.9±1.5 and 25.4±2.5 °C, respectively, using the NPC and DDC systems. Sow daily feed intake, litter weight at weaning, piglet weight at weaning, litter daily weight gain, piglet daily gain, and daily milk production per sow were greater in the NPC system than in the DDC system. The type of cooling system did not affect piglet weight after standardization, mortality, number of piglets weaned per sow, and estrus return. The use of an NPC system can reduce the effects of higher environmental temperatures better than the DDC system. The NPC system allowed for greater feed intake, piglet and litter weight gain, weight of piglets and litter at weaning, and milk production compared with the DDC system.
Abstract in English:ABSTRACT We evaluated the maternal behavior, physiology, and reproductive performance of both Damin (Min-pig × Large White) and Large White gilts to identify the advantages hybrid sows offer with regard to stress relieve and improvement of the welfare level of sows during late lactation. First-parity Damin gilts (n = 40) and first-parity Large White gilts (n = 40) were farrowed in individual pens. Video surveillance was used to monitor the occurrence of lateral recumbency and compare it to other postures, such as ventral recumbency, defecation, urination, tail posture, sham-chewing, and bar-biting behaviors. Monitoring was conducted from 07:00 to 09:00 h and from 13:00 to 15:00 h on days 3 and 6 of each week from the third to the fifth week post-parturition. In addition, the concentrations of tumor necrosis factor-α, interleukin-6, and salivary α-amylase were assessed. During the fourth week postpartum, Damin gilts showed a higher frequency of postural changes from lateral recumbency to other postures and less ventral recumbency, sham-chewing, and bar-biting behavior compared with Large White gilts. However, no significant differences were found between Damin and Large White gilts with regard to urination, defecation, tail wagging, and “tail low” behaviors. The concentrations of serum interleukin-6, salivary α-amylase, and serum tumor necrosis factor-α were higher in Damin gilts than in Large White gilts during the fifth week postpartum. Damin gilts partly achieve lower stress levels during late lactation and better animal welfare than purebred Large White gilts.
Abstract in English:ABSTRACT The objective was to study the stress level in dogs during grooming services in a pet shop. A total of 55 grooming services carried out in a pet shop in the city of Janaúba, MG, were evaluated and divided into four categories according to sex and body weight. The flowchart of the grooming process contained six steps that began with the transportation of dogs to the pet shop and finished with their return to the place of origin. Behavioral, physiological, and blood component evaluations were performed at different steps of the process. Changes in dog behavior and physiological parameters were observed primarily upon arrival at the pet shop and during drying. Employee characteristics also influenced dogs’ behaviors. However, dogs were able to thermoregulate and maintain the homeostasis of leukocytes, glucose and cortisol in the blood.
Abstract in Portuguese:ABSTRACT This study compared the social and feeding behaviour of immunocastrated female pigs using different immunocastration protocols. We used seventy-two gilts from industrial crossbreeding (Agroceres × Topigs) at 15 weeks of age. The pigs were distributed in a randomised design with three treatments. The second dose of the immunocastration vaccine was applied in two groups, six weeks before slaughter (I6) and four weeks before slaughter (I4). A non-immunised group (NI) was used for comparison. Due to the divergence in the time of immunisation between the two groups, an individual comparison of each immunocastrated group with the control group (NI vs. I6 and NI vs. I4) was performed. Social behaviour was analysed through the collection of images by a monitoring camera, and the analysis period was from 6:00 to 18:00 h, with behaviour observed every ten minutes. Feeding behaviour data were collected by the automated FIRE® system. Anti-GnRH immunisation and the different protocols of application did not influence most social and feeding behaviours.
Abstract in English:ABSTRACT The effects of dietary digestible protein (DP) levels (22, 26, 29, 32, and 34%) and different stressors (cold-induced stress, CIS; heat/dissolved oxygen-induced stress, HDOIS; transport-induced stress, TIS; and size-sorting-induced stress, SSIS) on hemato-biochemical parameters were evaluated. Four hundred and forty Nile tilapia fingerlings were distributed into 40-250 L aquaria and fed experimental diets for 110 days, and fed each of the five experimental diets, that were randomly distributed to eight replicates per treatment. Then, different groups of fish were subjected to one type of stress. Groups of 40 fish were used on CIS (17 °C), HDOIS (32 °C), and TIS (4 h), and a group of 140 fish on SSIS (15 min air exposure and 60 s handling). There was no effect on hemato-biochemical profile when DP levels were compared, neither before nor after stress; however, there was a significant stress effect. Digestible protein did not mitigate stress response under SSIS and CIS; lymphopenia and neutrophilia were the main cell-mediated immune response; dietary 22 and 26% DP impaired oxygenation on SSIS and TIS; fish under HDOIS and SSIS demanded more energy using triglycerides as an energy source; the diet formulated to contain 22% DP was not adequate to keep homeostasis under temperature stress. Cluster analysis showed that, for DP levels below the requirement for growth, SSIS and CIS were considered the most stressful conditions. At 34% DP level, HDOIS response was comparable to that of non-stressing conditions.
Abstract in English:ABSTRACT The objective of this study was to assess a training protocol employed in the Brazilian Northeast region for fitness conditioning of vaquejada horses. For 12 months, 24 Quarter Horses were evaluated under a completely randomized split-plot experimental design in which the plots comprised three age groups: horses at two, three, and four years of age. The split plots were made up of six fitness tests carried out every other month. The fitness test protocol consisted of five levels of protocol exercises on a standard vaquejada track. Prior to the tests with fasted animals, we collected blood samples to determine muscle enzymes (aspartate aminotransferase, creatine kinase, and lactate dehydrogenase). During the tests, heart rate, speed, and distance run were recorded using a heart rate monitor. Next, the results were used to calculate speed at which each horse reached 150 bpm (V150), speed at which each horse reached 200 bpm (V200), maximum heart rate (HRmax), maximum speed (Vmax), recovery time needed for the heart rate of horses to return to half the maximum value reached during the fitness tests (HR50%), and recovery time needed for the heart rate of horses to return to baseline values (HRbasal). No difference was found among the age groups for V150, HRmax, Vmax, HR50%, HRbasal, or muscle enzymes. By the final stage of training, the V200 of the three-year-old horses was higher than that of the four-year-old foals. During training, all groups exhibited increases in serum concentrations of muscle enzymes and reductions in efficiency to recover heart rate after exercise. The training protocol assessed is unable to maintain proper fitness for competitions throughout the year.
Abstract in English:ABSTRACT The objective of this study was to elucidate the optimum protocol timing of thermal manipulation (TM) during embryogenesis, which underline genetic improvement of muscle thermotolerance acquisition. For the present study, 1,440 fertile eggs were divided randomly and equally into control (37.8 °C with 56% relative humidity) and four thermally manipulated groups (TM1, TM2, TM3, and TM4) subjected to 39 °C for 18 h with 65% relative humidity daily during different embryonic periods. Then, at day 35 post-hatch, all groups were subjected to thermal challenge at 43 °C for 6 h to identify the level of thermotolerance acquisition differences between them. Hsp70 mRNA expression was evaluated by using a relative quantitatively RT-qPCR. Single nucleotide polymorphisms sequence of the Hsp70 gene was evaluated by Sanger's sequencing method. Pectoral and thigh muscles samples were subjected to immunohistochemistry to detect Hsp70. Among TM conditions that were investigated, TM1 (39 °C for 18 h during embryonic days (ED) 7–11) induced a significant improvement in thermotolerance parameters (body temperature and T3 levels) during thermal challenge combined with an increase in the levels of Hsp70 mRNA and its protein with a high stability of nucleotide sequences in both pectoral and thigh muscles. The partial DNA sequence of Hsp70 gene in TM1 was reported, and nucleotide sequences were deposited in NCBI GenBank database with the accession numbers (MK852579) and (MK852580). Thigh muscle thermotolerance acquisition was higher than pectoral muscle during thermal challenge at 43 °C for 6 h. Thus, TM during ED7–11 may improve thermotolerance acquisition without adversely affecting performance.
Abstract in English:ABSTRACT The objective of this study was to evaluate the breed and heterosis effects on reproductive traits, test-day milk yield, and 305-day milk yield in different lactations of crossbred Girolando cows. Data consisted of test-day milk yield records of first (118,831 records), second (63,227), and third lactation (44,512) and their relative productive (test-day milk yield, 305-day milk yield, and lactation length) and reproductive (age at first calving, calving interval, days open, and dry period) records of 35,582 Girolando cows from Brazil, collected from 1998 to 2014. The heterosis effect of the evaluated traits in Girolando cattle was estimated by MIXED procedure in SAS. Girolando cows showed a negative (favorable) and significant heterosis effect for reproductive traits. The dry periods between the first and second calving and between the second and third calving showed the greatest gains in heterosis (21.93 and 10.41%, respectively). All the evaluated productive traits showed a significant and similar heterosis effect between the three lactations. The use of crossbreeding strategies between the Holstein and Gyr breeds, instead of using the pure breed, is indeed a good alternative to increase the economic efficiency of the dairy activity in the different production systems in tropical environments.
Abstract in English:ABSTRACT The objective of the present study was to evaluate the stability of candidate reference genes and select the genes that can be used for normalizing real-time polymerase chain reaction (PCR) in the liver, skeletal muscle, and jejunum tissues of Nellore or Nellore × Angus steers fed different diets. Fourteen purebred and 14 crossbred steers were used, in which half of the animals of each genetic group received a diet containing whole shelled corn (WSC) and the other half whole shelled corn and sugarcane bagasse (WSCB). Stability was analyzed by the RefFinder program. To validate the selection of candidate reference genes, the expression of target genes was evaluated using the different groups of reference genes. The most stable genes were 18S, ACTB, and CASC3 for skeletal muscle; HMBS, ACTB, and 18S for the liver; and GAPDH, ACTB, and CASC3 for the jejunum, regardless of breed and diet provided. Possible errors caused in data analyses were clarified comparing the more and less stable genes as reference for normalization of the target genes FASN, ACOX, SCD1, MGAM, and SLC2A1. The use of the more stable and less stable sets of reference genes may lead to different conclusions in respect to the expression profile of the target studied gene. The selection of more suitable reference genes for each experiment is of utmost importance to ensure the reliability of gene expression studies so that they can be applied in practice.
Abstract in English:ABSTRACT The objective of this work was to describe morphology and grouping of Paspalum notatum accessions, based on multicategorical data which discards the redundant variables for quantification of genetic diversity. We also tested the hypothesis that geographical distance was correlated with morphological divergence. In our study, multivariate analyzes successfully demonstrated the geographic and morphological variability of the P. notatum accessions characterized. Many of these evaluated accessions can be included in future genetic improvement programs. Based on two methodologies for discarding variables, it was possible to identify the potentially important morphological characteristics from genetic diversity studies and characterize new accessions aimed at improving forage and seed production. The methodologies used to discard variables are biometric tools that can be used successfully in future plant breeding programs, especially when a large number of traits and accessions are being evaluated. Although significant, geographic distance had a low association with morphological traits. This indicated the need to use other characteristics, such as forage and seed yield, in addition to molecular analysis. Our analyzes showed genetic variability in P. notatum for all the characteristics studied.
Abstract in English:ABSTRACT This study aimed to introduce R package pedSimulate, which was built to simulate pedigree, genetic merit, phenotype, and genotype data. These are amongst the most important data types that animal breeders and quantitative geneticists deal with. Twenty pedigrees with ten generations were simulated applying different combinations of three parameters: genetic variance (10 vs. 20), proportion of males selected (10 vs. 20%), and the pattern for selecting females (random, positively, or negatively based on own phenotype or parent average). Males were selected positively based on parent average. Consequently, assortative mating was applied to the pedigrees in which females were positively selected based on their own phenotype or parent average. Disassortative mating was applied to the pedigrees in which females were selected negatively based on phenotype or parent averages. Genetic gain and response to selection over generations were positive for all the pedigrees due to high selection intensity on males, mating each male with multiple females, and moderate to high heritability (0.25 and 0.40 for genetic variances 10 and 20, and the residual variance of 30). Genetic variance showed a slightly increasing trend over generations by assortative mating and lower selection intensity on males. Selection intensity on females was the same in all the pedigrees. This study provided examples of how R package pedSimulate can be adopted for pedigree, genetic merit, phenotype, and genotype data simulation in animal breeding studies. By using different functions and combining different parameters for their arguments, many scenarios can be simulated by R package pedSimulate.
Abstract in English:ABSTRACT We aimed to estimate genetic parameters for growth, reproductive, and carcass traits in Tabapuã cattle. Phenotypic data were collected between 1990 and 2019 in 1,218 farms, and the pedigree file had 340,868 animals. The traits evaluated were body weight at 120 (W120), 210 (W210), 365 (W365), and 550 (W550) days of age; age at first calving (AFC), scrotal circumference at 365 days of age (SC365), ribeye area (REA), backfat thickness (BF), and rump fat thickness (RF). The (co)variance components were estimated using the restricted maximum likelihood method, considering single and two-traits animal models. For all traits, the models considered fixed, direct additive genetic, and residual random effects. In addition, for W120 and W210, the maternal additive genetic and maternal permanent environmental effects were also included. Heritabilities for W120, W210, W365, W550, SC365, REA, BF, and RF were of moderate magnitude (0.15, 0.16, 0.23, 0.19, 0.22, 0.36, 0.31, and 0.27, respectively). Low heritability was observed for AFC (0.07). The genetic correlations between growth traits were higher than 0.90, while AFC and SC365 presented negative moderate correlation (−0.66). The REA showed low genetic correlations with BF (0.07) and RF (0.07), whereas BF and RF were highly correlated (0.77). Considering the heritability estimates, selection for AFC would result in limited genetic gain, while for the other traits, it would be satisfactory. Based on the high genetic correlations between growth traits, selection of Tabapuã animals can be performed at younger ages. Additionally, animals can be indirectly selected for AFC through SC365, and only one fat thickness trait may be used in the selection process considering the high genetic correlation and similar heritability values for BF and RF.
Abstract in English:ABSTRACT The objective was to evaluate the existence of heterogeneity of variances and its impact on the genetic evaluation of ponderal performance in sires of the Nellore breed. We used records of adjusted body weights at 210 (W210), 365 (W365), and 450 (W450) days of age. Both W365 and W450 were combined by principal component analyses using the first component (PC). Average daily gain (ADG) was obtained by difference between W450 and W210. The classes of standard deviations (SD) for W210, PC, and ADG were obtained by the standardization of means of herd-year means subclasses, with positive values composing the high SD and values equal and less than zero composing the SD. The model included the fixed effects of contemporary group and age at calving as a covariate, random genetic additive, and maternal genetic (except for PC) effects, and the permanent maternal environment. Variance components were obtained by Gibbs sampling. Posterior means of heritability in analyses without considering heterogeneity of variances ranged from 0.15±0.01 to 0.31±0.01. Posterior means of genetic correlations between the two classes of SD for W210, PC, and ADG were equal to 0.85±0.04, 0.83±0.03, and 0.71±0.08, respectively. Spearman correlation to breeding values of sires for ADG as the selection intensity increased in them, and the correlations between breeding values in general analyses were more correlated with those predicted in the high DP. Therefore, when there is a higher selection intensity on the sires only for the ADG criterion, there is a significant presence of the heterogeneity of variances and impact on the genetic evaluation of the sires. Thus, for ADG, the predictions of breeding values obtained by the genetic evaluation model in which the heterogeneity of variances are not considered are more weighted by the class of greater heterogeneity.
Abstract in English:ABSTRACT The objective of this work is to estimate genetic parameters and breeding values to improve embryo and oocyte production, using repeatability and random regression models (RRM) for Gir dairy cattle. We used 11,398 records of ovum pick-up from 1,747 dairy Gir donors and evaluated sixteen different models: the traditional repeatability model and fifteen RRM, each of which considered a different combination of Legendre polynomial regressors to describe the additive genetic and permanent environment effects. The 4G1P model (four regressors for the genetic effect and one regressor for the permanent environment effect) is the most suitable model to analyze the number of viable and total oocytes, while the 3G1P is the best model to analyze the number of cleaved and viable embryos, according to the values of the Akaike information criterion (AIC) and the Bayesian information criterion (BIC). The heritability estimated with the RRM was higher than that estimated with the repeatability model. The high repeatability reported for oocyte and embryo count traits indicates that donors, which had high oocyte and embryo counts in the first ovum pick-up, should maintain this result in the next ovum pick-up. Genetic correlations between adjacent ages were high and positive, while genetic correlations between extreme ages were weak. We observed a reranking of the top sires and females (heifers and cows) over the period evaluated. The reliability of the estimated breeding values by RRM showed changes across age, and the expected genetic gains by RRM are larger. This shows that RRM is most suitable alternative for the evaluation and selection of oocyte and embryo count traits.
Abstract in English:ABSTRACT We aimed to reduce the dimensionality of quantitative traits in pigs applying factor analysis. Quantitative variables were collected, and the factor analysis extracted five factors with biological meaning related to performance, carcass quality, carcass yield, meat quality, and initial pH. These factors were posteriorly used as dependent variable to evaluate the effects of genetic groups (Piau, Duroc, and Pietrain crossbreds), nutritional plans (low, medium and high lysine levels) and sex. An interaction effect between genetic group and sex was observed in performance, in which Duroc crossbred showed the greatest scores. The Pietrain genetic group showed greater values of carcass quality compared with Duroc and Piau, while Piau crossbred pigs had greater values for meat quality compared with Pietrain and Duroc. A greater carcass yield was observed in Pietrain crossbred compared with Duroc pigs. Pigs fed under low lysine level had the lowest performance values. Carcass yield was affected by nutritional plans, in which the medium lysine level showed the greatest values. Meat quality was improved by the nutritional plan with high lysine level compared with the low lysine level. Initial pH showed increased means when using nutritional plans with low and medium lysine levels in diet composition. With regard to sex effects, a greater carcass quality was found for gilts compared with barrows. The reduction of the data dimensionality allowed the joint evaluation of genetic group, nutritional plan, and sex based on new latent variables that represented the original dataset under easier framework based on factors’ biological interpretation.
Abstract in English:ABSTRACT The objective of this study was to investigate the effects of recombinant adiponectin on chicken liver cells. The full-length chicken adiponectin gene was amplified by PCR and cloned into the vector pET-32a, followed by the transformation of the vector into Escherichia coli BL21. SDS-PAGE was used to detect and analyze the purity of the expressed recombinant protein. Induction was performed with 1 mM IPTG at 30 °C for 3 h, and the recombinant thioredoxin–adiponectin fusion protein was purified using Ni-NTA affinity chromatography. Chicken adiponectin was successfully expressed and purified in a bacterial system. In addition, the chicken recombinant adiponectin demonstrated that it ameliorates palmitic acid- and oleic acid-induced adipogenesis, in which an increase in β-oxidation and a decrease in lipogenesis-related genes may be involved. In summary, chicken recombinant adiponectin enhances fatty acid metabolism in LMH cells.
Abstract in English:ABSTRACT The objective was to evaluate the effect of different irrigation systems and harvest frequencies on the cultivation of cactus pear. The study was conducted in the semi-arid region, in the municipality of Russas, CE, Brazil. The experiment was a split plot randomized block design, with four replications. Plots were represented by irrigation systems (surface drip, microsprinkler, Micro Spray Jet, and conventional sprinkler) and subplots by harvest frequencies (6, 9, 12, and 18 months). Cactus pear biomass production characteristics were evaluated. Most of the productive characteristics evaluated were influenced by harvest frequency and irrigation system. The harvest frequency of 12 months combined with conventional sprinkler system resulted in a total dry biomass production of 16,400 kg ha−1. The conventional sprinkler system showed the highest number of second-order cladodes (4.9 cladodes plant−1). The conventional sprinkler and Micro Spray Jet systems showed the highest values for various structural characteristics. For water use efficiency (WUE), the highest value was found at the frequency of six months (8.46 kg ha−1 mm−1). Regarding the effects of irrigation system on WUE, the highest values were observed with the conventional sprinkler system (8.20 kg ha−1 mm−1). The harvest frequency of 12 months combined with the conventional sprinkler system presents better results in the evaluated productive characteristics, mainly the cactus pear production by area.
Abstract in English:ABSTRACT The objective of this research was to identify the existence of root exudation of organic acid in Lotus corniculatus germplasms subjected to toxic aluminum (Al) levels and investigate the effect of this mechanism on the Al content in the root tissue and in morphological parameters of plant development. Two experiments were performed in nutrient solution to evaluate the Al accumulation and exudation of organic acids, using cultivars INIA Draco and São Gabriel and genotypes UFRGS and UF-T2. The plants were cultivated in Al-free solution, which was applied on the 45th day in half of the pots of each genotype. Root exudation was highly correlated with the reduced accumulation of Al in the root tissue (r2 = 0.75 at 72 h). Genotype UF-T2, selected for Al tolerance, extruded 80% more oxalic acid in the presence of Al compared with the other germplasms, indicating that this mechanism is involved with Al tolerance in L. corniculatus. This experiment showed strong evidence that L. corniculatus exhibits Type I tolerance, in which anionic channels are rapidly activated by Al exposure. Exudation of oxalic acid is likely a crucial mechanism that allows the maintenance of L. corniculatus growth when exposed to toxic Al conditions, and this characteristic should be used to identify tolerant genotypes in the future.
Abstract in English:ABSTRACT The objective of this study was to evaluate the effect of harvesting corn at different maturity stages for silage production combined with four storage periods, considering nutrient loss and the chemical composition of silage of the whole plant and also of grainless plants. The experiment was performed in a completely randomized design with a factorial arrangement of six maturity stages of corn [reproductive (R); R1 to R6] and four periods of silage storage (30, 60, 90, and 120 days). At stages R1 and R2, losses by effluents occurred more intensely when compared with the more advanced stages, whereas losses by gases showed the opposite behavior, with stage R6 responsible for the greatest losses. Stage R4 showed a stable dry matter (DM) content during the storage period, 42.08%, and had the lowest levels of neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) for the whole plant silage. The ADL in the silage of grainless plant of stage R4 was not the lowest, but it was close to the first reproductive stages, being an important point, since the first reproductive stages can present a vegetative fraction of better quality. The highest DM volumes produced by area occurred in the most advanced stages; however, R5 obtained a greater reduction in volume over the days of storage (20.66 kg day −1 ). The production cost was lower at the advanced stages (R4, R5, and R6) when compared with the first reproductive stages (R1, R2, and R3), and in general, during the storage period the costs did not have great variations. Based on the chemical composition of the silages, DM losses during the storage period, the stability in the costs of DM ton over the days of storage, the R4 stage was the most suitable for silage production.
Abstract in English:ABSTRACT Integrating warm-climate forage legumes into grass monocultures has received significant research attention during the past 70 years, but widespread adoption by end users has been elusive. The objectives of this review are to provide historical context regarding legume use in warm-climate grasslands; synthesize the current literature addressing contributions to grassland ecosystem services of warm-climate, grass-only vs. legume-grass mixed swards; and consider how to achieve more widespread adoption of legume technology in warm climates. For this review, warm-climate grasslands are considered those in areas between latitudes 30° N and 30° S, where C4 perennial grasses dominate. The literature suggests measurable advantages in animal performance, soil carbon accumulation, and nutrient cycling of legume-grass mixtures are most likely when grass-only swards receive little or no N fertilizer. Advantages are less or may disappear when mixtures are compared with grasses receiving high N fertilizer rates. In contrast, amelioration of greenhouse gas emissions is often most pronounced for mixtures when compared with grass-only swards receiving high rates of N, because of the magnitude of N fertilizer effects on emissions. Going forward, there is need to focus on selecting for, and thoroughly documenting legume persistence, achieving low-risk and affordable legume establishment methods, assessing compatibility of legumes in mixture with grasses prior to legume cultivar release, emphasizing adoption of both legume species and optimal management practices, and recognizing scientists must assume a larger and more intentional role in encouraging adoption by end-users of research innovations, in addition to our traditional role in technology and product development.
Abstract in English:ABSTRACT The objective of this study was to evaluate the effects of ginger as an additive in the diet of fattening rabbits. Sixty weaned rabbits (35 days old) were randomly assigned to four groups (n = 15). Animals were fed ad libitum with a control diet or one of three experimental diets supplemented with 0.5, 1, and 2 g of ginger per 100 g of feed during 28 d. Weight gain in the final week of the experiment was significantly greater in rabbits fed ginger at 0.5 g/100 g of feed than in those fed ginger at 1 and 2 g/100 g of feed or the control diet. No significant differences in morphometric measurements were observed among the treatments, but higher values of live weight, carcass length, and carcass circumference were observed in rabbits treated with ginger than in those fed the control diet. Regarding carcass quality parameters involving the kidneys and empty gastrointestinal tract, we found that rabbits treated with ginger at 0.5 g/100 g of feed showed significant differences from those treated with ginger at 1 and 2 g/100 g of feed or the control diet. pH, water holding capacity, L*, and a* did not significantly differ among the treatments, although greater water holding capacity was observed in rabbits treated with ginger than in control rabbits. Parameter b* was significantly higher in rabbits fed ginger at 2 g/100 g of feed than in those fed at 0.5 and 1 g/100 g of feed and in the control. The results found suggest that ginger can be used as an additive in diets of fattening rabbits.
Abstract in English:ABSTRACT The objective of this study was to evaluate the effects of dietary supplementation of purified lignin on the performance, relative organ weights, serum metabolites, and gene expression profiles of broiler chickens subjected to cyclic heat stress (HS). At 22 days old, 280 broilers were distributed in a completely randomized design with four treatments, ten repetitions, and seven birds per experimental unit. The birds were subjected to daily cyclic HS. A high temperature of 32±1 °C was maintained for 10 h/day (08:00–18:00 h), while a temperature of 22±1 °C was maintained for the remaining time. Treatments were a basal diet or basal diet with the addition of 5, 10, or 15 g of purified lignin/kg of diet. Data were analyzed using one-way ANOVA and means were compared by Tukey's test at 0.05 significance. There was no effect of lignin supplementation on performance, carcass yield, relative weights of the bursa, spleen, and liver, or serum levels of glucose, triglycerides, uric acid, malondialdehyde, triiodothyronine, or tetraiodothyronine. The abundance of mRNA of heat shock protein 70, nuclear factor-κB, glutathione peroxidase, and Cu,Zn-superoxide dismutase in the liver was similarly unaffected by treatments. Purified lignin supplementation does not improve performance or the antioxidant response of broiler chickens subjected to HS.
Abstract in English:ABSTRACT The objective of this study was to determine and compare the chemical composition; oxidation indicators; ether extract (EE) digestibility; and digestible, metabolizable, and net energy (DE, ME, and NE, respectively) content of distillers corn oil (DCO) from Brazil (CBR) and the United States (CUS), with refined (RSB) and degummed soybean oil (DSB) from Brazil offered to pigs. Fifty crossbred barrows (23.1±3.4 kg body weight) were fed a corn-soybean meal basal diet, or diets composed of 90% basal diet and 10% of one of the four oil sources (CBR, CUS, RSB, or DSB). Pigs were fed an amount of their respective experimental diets equivalent to 2.8 times the maintenance DE requirement for 9 d (sequentially 7 d for adaptation and 2 d for partial collection of feces). Distillers corn oil from Brazil contained lower linoleic acid (47.4%) than CUS (53.9%), RSB (54.2%), and DSB (51.5%), but greater contents of oleic (32.1%) and palmitic (14.6%) acids compared to CUS (27.0 and 12.9%), RSB (22.9 and 11.2%), and DSB (23.5 and 11.2%). The moisture and unsaponifiable contents of CBR (0.17 and 1.64%) and CUS (0.20 and 1.64%) were similar, but greater than the values found for RSB (0.05 and 1.20%) and DSB (0.12 and 1.02%). The anisidine value, free fatty acid content, and acidity of DCO samples were higher than soybean oils. The peroxide value and thiobarbituric reactive substances content increased in the oil samples over time. The apparent total tract digestibility (ATTD) of gross energy and the DE, ME and NE values of the oils did not differ among oil sources and ranged from 87.8 to 91.5%, and from 8280 to 8630, 8139 to 8459, and 7162 to 7444 kcal/kg, respectively. The ATTD of EE was greater in RSB and DSB than for CBR, but similar to CUS. The DCO produced in Brazil is an excellent energy source for pigs, with DE, ME, and NE values similar to those of DCO from the US and soybean oils.
Abstract in English:ABSTRACT The objective of this study was to evaluate the effect of pre-farrowing lipid supplementation for three days on performance parameters of sows and piglets and the survival rate of litters. Four hundred hyperprolific sows were randomly distributed in blocks according to their body condition score, weight, and parity order. Three levels of soybean oil were added on top at the time of feed supply and compared to the control treatment. The levels were: 250 mL, 500 mL, and 1,000 mL, in addition to the control that contained only the crude fat present in the feed (5.04%). Sows were weighed and evaluated for their body condition score at the beginning and end of the lactation period, and their piglets were weighed at birth, after 24 h, and at weaning to determine colostrum yield of the sow and daily weight gain of piglets during the lactation period. Survival rate of litters was also evaluated. Weight loss of gilts decreased linearly as the level of supplemented oil increased. The other parameters evaluated were not affected by treatments, suggesting that the supplemented soybean oil was used for growth rather than milk production of gilts. Additionally, it had no effect on the performance of multiparous females. Under the experimental conditions of this study, soybean oil supplementation for gilts in the first three days before farrowing decrease their weight loss but does not change their body condition score, colostrum yield, and performance and survival of their litters.
Abstract in English:ABSTRACT This study evaluated the effects of two protein levels and types of formulation on performance, nutrient metabolization, and myopathies of 390 female broilers from 21 to 46 days old distributed in a completely randomized design, with five treatments and six replicates of 13 broilers each. Treatments were two levels of protein (19.0 and 21.0%) in diets using only commercially available ingredients and three experimental formulations designed to keep similar the main nutrients that could influence nutritional performance (starch, fiber, ether extract), using unusual ingredients, with 19.0% (19E) or 21.0% (21E) crude protein and the third with 19.0% crude protein with amino acid levels similar to treatment 21P (19E+Aa). We studied broiler performance, nutrient digestibility, macroscopic muscular evaluation, and histological muscular evaluation. The design for the performance and myopathy assessment was a 5 × 2 factorial scheme, five diets × two ages (38 or 46 days). The worst feed conversion ratio was observed for the 19P treatment. Neither diet nor age had an effect on myopathies, however, older slaughter age increased the intensity of microscopic lesions. The diet 19P should be avoided and increased inclusion of lipids in diets improves nutrient utilization and, consequently, performance.
Abstract in English:ABSTRACT Three experiments were carried out to evaluate the effect of dietary combination of different enzymes (phytase + protease) on performance, metabolizable energy, and amino acid digestibility of broiler chickens fed diets with nutritional reduction. A total of 1,400, 336, and 384 male chickens were distributed in a completely randomized design, in the experiments of performance, metabolism, and digestibility, respectively. Treatments were divided as follows: positive control (PC), negative control - NC1 (PC minus 0.16% Ca, 0.15% available P (aP), and 0.5% crude protein (CP)), NC2 (PC minus 0.16% Ca, 0.15% aP, and 1% CP), NC1 added with phytase deriving from citrobacter and protease deriving from Bacillus licheniformis (CBE), NC1 added with phytase deriving from E. coli and protease deriving from microbial fermentation (SE), NC2 added with CBE, and NC2 added with SE. A protein-free diet was included in the digestibility experiment. The nutritional restriction did not affect feed intake of birds in the first experiment; however, the restriction inhibited body weight gain and feed conversion ratio in all phases. In experiment 2, the nutritional restriction decreased AME and AMEn values, although the addition of phytase and protease in diets improved both parameters, mainly in NC2. Treatment NC2 impaired the standardized digestibility of total essential amino acids of animals subjected to experiment 3, although the addition of enzymes helped to recover the digestibility to levels similar to PC. Supplementation of phytase in association with protease is effective to improve performance, energy metabolism, and standardized amino acid digestibility of broilers fed diets with nutrient restriction.
Abstract in English:ABSTRACT We examined the effect of dried distillers grains with solubles (DDGS) in diets for late gestating sows on sow and litter performance, colostrum chemical composition, and sow behavior. Sixty gestating sows of 3.77±1.65 parity were divided into three groups of 20 animals, in a randomized block design with 0 (corn-soybean meal diet), 150, or 300 g kg−1 DDGS from 84 days of gestation until farrowing. Sows fed 300 g kg−1 DDGS presented a lower frequency of standing position and eating activity. The lying lateral position was more frequent in the first 40 min post-feeding for sows fed the highest DDGS level. There was no effect of diets on sow and litter performance; however, DDGS inclusion tended to increase lactation feed intake. Inclusion of DDGS was inclined to produce more lactose and less protein in colostrum, but did not affect colostrum fat, total solids, and ash contents. Inclusion of up to 300 g kg−1 DDGS in the diet of late gestation sows does not change sow and litter performance and colostrum composition compared with corn-soybean meal diets, but it favored animal welfare.
Abstract in English:ABSTRACT An experiment was conducted to evaluate the effect of the intake of a mixture of fish and sacha inchi oils (iOM), organic selenium (iSe), and organic chromium (iCr) on egg production (EP) and feed conversion ratio (FCR) of Isa Brown second-cycle laying hens (SCLH) for 16 weeks (91-106 weeks old). Egg production and FCR were evaluated using multivariate models that included conventional equations and artificial neural networks (ANN) to study multiple nutritional interactions as alternatives to univariate dose-response models. Based on the best models, iOM, iSe, and iCr levels were optimized, and a global sensitivity analysis was implemented to quantify their influence on EP and FCR. The modified logistic model was selected as the best strategy to represent EP. In the case of FCR, an ANN model with a feed-forward architecture and softmax transfer function was selected as the best alternative. One of the scenarios to simultaneously optimize EP (89.1%) and FCR (1.94 kg feed/kg egg) at 16 weeks of production was established with 3.3 g/hen·day of iOM, 0.132 mg/ hen·day of iSe, and 0.176 mg/hen·day of iCr. However, optimization considering only FCR results in much lower optimal iCr levels (between 0.083 and 0.105 mg/hen·day) with a slight decrease in EP (87.9%). The global sensitivity analysis showed that iSe is an essential factor associated with the increase in EP, and iCr is the most influential factor for the decrease in FCR. When both criteria were taken into account simultaneously from a desirability function, iSe was the most critical factor.
Abstract in English:ABSTRACT This study evaluated the effects of including Moringa oleifera (moringa) leaf meal on performance, carcass yield and characteristics, and relative organ weights of broilers from 10 to 42 days of age. We distributed 420 male Cobb 500 chicks in a completely randomized design with five treatments and six replicates with 14 birds each. Treatments consisted of five experimental diets in which the moringa leaf meal was included at 0, 1.5, 3.0, 4.5, and 6.0% in the diets. The following performance variables were evaluated: weight gain, feed intake, and feed conversion; weights and yields of carcass, carcass traits, organs, and abdominal fat; and feet color. Significant differences between the treatment means were analyzed by Dunnett’s test. The meal inclusion levels did not affect performance, carcass characteristics and yield, or organs weight. However, feet pigmentation increased linearly, and abdominal fat was greater only at the 1.5% level when compared with the control group. Moringa leaf meal can be included in the diet of broilers from 10 to 42 days of age, up to the level of 6%, without compromising performance or carcass yield of these birds.
Abstract in English:ABSTRACT The aim of this study was to assess the addition of intestinal alkaline phosphatase (IAP) to diets on the count of bacterial populations, pH of digestive organ contents, histopathological description, proinflammatory markers, hepatic glycogen reserve, and diarrhoea incidence of piglets challenged with Escherichia coli. Sixty-four crossbred piglets (7.16±0.28 kg body weight, 25-days-old) were assigned to four treatments in a completely randomised block design: negative control (NC), NC + antibiotic (ANT), NC + 15 mg IAP, or NC + 30 mg IAP kg−1 of diet, eight replications of two piglets per experimental unit. All piglets were orally challenged with 6 mL of a solution containing enterotoxigenic Escherichia coli K88 at 106 CFU mL−1 at 15 days of experimentation. The study lasted for 19 days. At the end of the experimental period, the piglets were slaughtered (six animals per treatment). Enterobacteriaceae in caecum and colon was lower in piglets on 30 mg IAP than with ANT and NC, ANT or 15 mg IAP, respectively. Enterobacteriaceae adhered to the mesenteric lymph nodes (MLN) was greater in piglets fed ANT than the other treatments. Lactic acid bacteria (LAB) count in caecum was greater in piglets fed NC and ANT. In MLN, LAB count was greater in ANT and 30 mg IAP-fed piglets compared with 15 mg IAP. Piglets in 30 mg IAP in diet showed a tendency for lowering tissue necrosis compared with NC or ANT. Piglets fed 30 mg IAP showed a reduction in diarrhoea incidence in the pre- and post-challenge compared with 15 mg IAP and all other treatments, respectively. Based on the criteria, addition of 30 mg IAP to diet inhibits Enterobacteriaceae population and suggests a potential effect in mitigating intestinal injuries, as observed in piglets in the NC for some of the parameters investigated.
Abstract in English:ABSTRACT Two experiments were carried with broilers from 29 to 42 days of age for the nutritional evaluation of dietary chia. Thus, the nitrogen-corrected apparent metabolizable energy (AMEn) and the apparent metabolizability coefficients of gross energy and ether extract of chia seeds and oil, toasted soybean grain (TSG), and soybean oil were determined in the experiment I, by total excreta collection method, using 120 broilers. Each experimental diet (reference diet [RD] and four diets with the tested feedstuffs) was evaluated in eight replicates of three broilers. The TSG and chia seeds replaced the RD in 250 g/kg, whereas soybean and chia oils replaced the RD in 100 g/kg. Simultaneously, a second experiment was carried subdivided into two trials. In the performance trial, we evaluated the dietary feedstuffs effects on performance, carcass and cut yields, blood parameters, and activity of lipogenic enzymes. The nutrient metabolizability coefficients and AMEn were evaluated in the metabolism trial. The AMEn values of 37.49, 37.35, 15.85, and 8.43 MJ/kg of dry matter were determined for chia oil, soybean oil, TSG, and chia seeds, respectively (experiment I). In the second experiment, the best feed conversion was observed in broilers fed diets containing chia oil and TSG. However, the diet formulated with chia seeds worsened broiler feed conversion, exhibited the smaller energy value and apparent metabolizability coefficient of the ether extract, and increased the activity of the malic enzyme and serum total cholesterol level. There was no difference for glucose-6-phosphate dehydrogenase activity and high-density lipoprotein cholesterol level. In general, chia oil showed to be efficient in replacing soybean oil in broiler diets.
Abstract in English:ABSTRACT This study was conducted to assess the effects of maternal dietary calcitic seaweed (CSW) on performance and blood metabolites of sows, and on performance, blood metabolites, intestinal microbiota, and parameters of gastrointestinal tract and bone of litters. On d 21 (post-insemination), non-pregnant sows were removed from the trial, remaining 19 sows in control group (without CSW) and 16 sows receiving CSW. Then, a total of 35 sows were allocated in a randomized block design with two treatments: control diet with calcitic limestone plus dicalcium phosphate (CTL) or CTL plus 0.4% CSW. In gestation, sows were fed twice a day (07:00 and 15:00 h) to reach an intake of 2.5 kg animal−1 day−1 divided into two equal meals. On parturition day, sows were offered only 0.5 kg feed animal−1. Throughout lactation, sows were fed three times a day (≅7 kg animal−1 day−1). All diets were provided as mash. Results suggested that sows fed CTL had litters with lower body weight at birth compared with those fed CSW. Sows fed CSW had 14.28% more live-born piglets and lower stillborns. Piglets from sows fed CSW showed greater calcium concentration on d 14 after birth than those from sows fed CTL. Sows fed CSW showed better milk chemical composition and an increase of 27.16% in milk production compared with those fed CTL. Piglets from sows fed CSW had an increase in cecum content in the Enterobacteriaceae count. This study showed that adding 0.4% CSW in the diet of pregnant and lactating sows as an organic calcium source positively influences the number of live-born piglets and the percentage of stillborns. In addition, milk composition and production are also improved without affecting piglets’ biological response.
Abstract in English:ABSTRACT The objective of this study was to evaluate whether replacing corn starch (CS) energy with isolated soy protein (ISP) and soybean oil (SO) and the ambient temperature affect the protein and energy requirements for maintenance and gain of European quail. Thus, a total of 432 European quail from 10 to 30 days of age, distributed in a completely randomized design, were used to estimate the protein and energy requirements for maintenance through the comparative slaughter methodology. The treatments consisted of three diets formulated with the replacement of CS, corresponding to 15% of the metabolizable energy in the diet, with ISP and SO, two controlled temperatures (26 and 35 °C), and three levels of feed supply (ad libitum, and 70 and 40% of ad libitum intake), with four replicates of six birds. Protein and energy requirements for weight gain were determined from 160 European quail, slaughtered every five days at 10, 15, 20, 25, and 30 days of age. Birds were housed in four groups of 40 birds in a room with thermoneutral temperature (26 °C). The energy sources of the feed and temperatures studied affected protein and energy requirements for maintenance and gain of European quail. Replacing CS energy by 15% of dietary energy with SO results in lower protein and energy maintenance requirements for European quail at both temperatures. The protein and energy weight gain requirements of quail fed SO as an energy source is higher than CS and ISP.
Abstract in English:ABSTRACT The objective of this study was to determine the effects that breeder age has on digestive and immune system development; the transfer of immunoglobulins to egg yolk, yolk sac, and neonate chicks; and the immune response of chicks up to 35 days old. Three ages (32, 42, and 52 weeks) of Hubbard breeders were studied with ages as treatments. A total of 425 eggs were weighed for each of the three treatments and incubated. After hatching, a total of 300 1-day-old chicks were used in each treatment. We studied the development of the gastrointestinal tract and immune system of progeny and IgY transfer from breeder to progeny. Chicks from 52-week-old breeders had greater gastrointestinal tract growth up to seven days of life and greater body weight at 14 days. Older breeders (52 weeks) had higher amounts of IgY in serum and egg yolk. Chicks from the youngest breeders (32-weeks-old) had a better immune response at two weeks post-vaccination. It can be concluded that the older breeders have a greater capacity to immunize progeny up to 14 days. Strategies can be developed to increase IgY in the serum of young breeders and, consequently, increase the innate immunity of the newly-hatched chicks.
Abstract in English:ABSTRACT This study was conducted to evaluate the effects of dietary supplementation with capsaicinoids on the performance and gene expression of broilers. At 18 days of age, 120 male broilers chickens (Cobb 500) were distributed in a completely randomized design with three treatments, eight replicates, and five birds per experimental unit. The treatments were a basal diet or basal diet with the addition of 1 or 2 mg of capsaicinoids/kg of diet. The birds had free access to water and feed throughout the experimental period (18 to 26 days of age). Broiler performance was evaluated at 26 days of age, and one bird per experimental unit was selected to collect serum and jejunum samples. Jejunum samples were used to analyze the mRNA content. Data were analyzed using one-way ANOVA, and the means were compared with Tukey’s test at a significance of 0.05. There was no effect of capsaicinoid supplementation on performance, serum metabolites, or the expression of glutathione peroxidase mRNA in the jejunum of broilers. However, broilers supplemented with capsaicinoids showed a higher mRNA expression of Cu, Zn-superoxide dismutase and a reduced mRNA expression of nuclear factor-κB in the jejunum. Supplementation with 1 and 2 mg/kg capsaicinoids did not improve the performance of broilers from 18 to 26 days of age but increased the mRNA expression of Cu, Zn-superoxide dismutase and reduced the mRNA expression of nuclear factor-κB in the jejunum of broilers.
Abstract in English:ABSTRACT The objective of this study was to evaluate the productive performance, apparent digestibility, and carcass and longissimus dorsi muscle characteristics of lambs fed diets supplemented with four levels of Saccharomyces cerevisiae. Thirty-two male Hampshire lambs (25.82±1.95 kg body weight) were distributed in four treatments: basal diet (20:80, forage:concentrate), and the inclusion of 0, 3, 5, and 10 g animal−1 d−1Saccharomyces cerevisiae. The variables evaluated were dry matter intake, daily weight gain, feed conversion, apparent digestibility, dorsal fat thickness, longissimus dorsi muscle area, and physicochemical characteristics of carcass and muscle. We used a completely randomized design and orthogonal polynomials to test the linear and quadratic effects of the inclusion levels of the yeast. Saccharomyces cerevisiae showed a quadratic effect on lamb performance. Dry matter intake decreased with yeast in response to a better feed conversion and body weight gain; however, at the highest Saccharomyces cerevisiae dose, daily weight gain and final weight were lower than with the basal diet treatment. Saccharomyces cerevisiae did not affect apparent digestibility or carcass and muscle physicochemical characteristics. Supplementation with 3 and 5 g d−1 Saccharomyces cerevisiae improves productive performance of lambs fed high concentrate diets without affecting the physicochemical characteristics of the carcass or muscle.
Abstract in English:ABSTRACT The study aimed to nutritionally evaluate the silage of pineapple crop waste in sheep feeding in different planes of nutrition (L). We used eight growing sheep and four male castrated adults, in individual metabolic cages distributed in a switch-back design with two treatments and three periods. The treatments were the different planes of nutrition: L = MEI⁄Mm, MEI⁄1.5Mm, and MEI⁄2.5Mm, in which L = MEI/Mm, MEI is the energy amount of the feed intake and Mm is the maintenance. We performed a digestibility trial of the diet composed of silage of pineapple crop waste, ground corn, and soybean meal. Data were analyzed using regression analysis. Nutrient intake behaved linearly according to the increase in the L, except for organic matter, which presented a quadratic behavior. Planes of nutrition did not affect protein and fiber digestible fractions. However, digestible fractions of fat and non-fibrous carbohydrates (NFC) increased with L. The indigestible fractions displayed a quadratic behavior with an increase in the L. Regarding the microbial synthesis efficiency, we observed a linear decrease with the increase in L. Thus, the silage of pineapple crop waste is a feed very rich in NFC. Besides, silage of pineapple crop waste presented a good alternative roughage during forage shortages. Diet inclusion of 2.5x the maintenance does not compromise the sheep performance.
Abstract in English:ABSTRACT The present study aimed to assess the productive performance, ingestive behavior, and thermal condition of crossbred beef heifers in an integrated livestock-forest (ILF) system with different tree-planting designs. Seventy-two ½ Angus ½ Nellore heifers were divided in three treatments—conventional system (CS) without eucalyptus, integrated livestock system with 187 eucalyptus ha−1 (ILF-1L), and integrated livestock system with 446 eucalyptus ha−1 (ILF-3L)—, in the winter and summer. Total dry mass of forage (TDM), chemical analysis of Marandu palisadegrass, average daily gain (ADG), stocking rate (SR), weight gain per area (WGA), behavior, microclimatic variables, and thermal comfort indexes were evaluated. A higher percentage of crude protein and lower TDM and SR were observed in ILF-1L and ILF-3L, with no differences for ADG and WGA. Ambient temperature, temperature-humidity index, black globe-humidity index, and radiant heat load were better in ILF-1L and ILF-3L. Heifers in ILF-1L and ILF-3L carried out grazing, resting, rumination, and other activities in the shade. In the summer, heifers in ILF-1L and ILF-3L spent less time resting and more time in rumination and performing other activities than those in the CS. In conclusion, the better forage quality in ILF-1L and ILF-3L does not alter the performance of heifers or WGA, despite the decreased TDM and SR. Furthermore, ILF-1L and ILF-3L provide better thermal comfort, and heifers that do not have access to shade decrease their activities as a strategy to reduce the use of energy for thermal regulation process.
Abstract in English:ABSTRACT This study was conducted to compare Central Anatolian Merino (CAM) and Malya sheep under intensive conditions in terms of reproductive traits, birth and weaning weights, fattening performance, and some fleece characteristics. In this study, 840 CAM and 194 Malya ewes were used for the comparison of reproductive performance, whereas 740 and 211 lambs were used to compare growth traits between the two breeds. Additionally, the fattening performance of 61 CAM and 68 Malya lambs were compared. Finally, for the comparison of wool quality traits, 94 CAM and 90 Malya lambs were used. The lambs were kept together with the sheep that gave birth to them for 10 days. After this period, lambs were given lamb starter feed, alfalfa hay, and vetch hay in addition to milk. When lambs reached 40 days old, they were taken to the pasture with the sheep. In this period, pasture grass, growing lamb concentrate feed, alfalfa hay, and vetch hay were given in addition to milk. Lambs were weaned when they reached an average age of 90 days, and their live weights were determined. A determined number of lambs was selected from weaned male lambs. For these animals, in the fattening period, barley, alfalfa hay, vetch hay, meadow hay, and lentil straw were provided ad libitum in addition to 400 g/day/head of fattening feed. This study indicated that birth rate was better for CAM sheep than for Malya sheep. However, Malya lambs may have more advantages than CAM lambs in terms of survival and fattening performance. Although birth weight was higher for Malya sheep than for CAM sheep, the opposite result was observed for the weaning weight. The beginning weights of fattened male lambs were higher for CAM lambs than for Malya lambs, but the ending weights of both fattened groups were similar.
Abstract in English:ABSTRACT The objective of this study was to evaluate the growth performance and meat quality of feedlot Aberdeen Angus steers fed high-concentrate diets with or without a natural feed additive composed of a mixture of yeasts and essential oils (EO). A completely randomized design with two diets (with or without natural feed additive) and 12 replicates was used. Twenty-four steers with initial shrunk body weight of 402.62±48.2 kg and average age of 18±2.0 months were used. Steers were fed ad libitum a diet containing 777.3 g of concentrate/kg dry matter (DM) and 222.7 g of corn silage/kg DM for 74 days. The mixture of yeast and EO was supplied at the rate of 10.0 and 0.117 g/animal/day, respectively. Average daily weight gain and feed efficiency in the adaptation period was greater in animals fed natural feed additive; however, there was no difference for the total experimental period. Dry matter intake, carcass weight, carcass yield, proportion of carcass bone, carcass muscle + fat:bone ratio, round thickness, and arm length were not altered by treatments. The inclusion of a natural feed additive in the diet increased the cooling loss (0.98 vs. 1.25%), proportion of carcass muscle (51.32 vs. 54.56%), carcass muscle:fat ratio (1.70 vs. 2.11%), leg length (68.79 vs. 70.71 cm), and arm perimeter (36.70 vs. 37.88 cm) and reduced the proportion of carcass fat (30.17 vs. 25.92%). Carcass length was greater in animals fed the diet with a natural feed additive. Meat color, texture, and marbling were not altered by treatments. The addition of natural feed additive to high concentrate diets does not alter the productive performance of feedlot Aberdeen Angus steers, although it can increase the proportion of lean meat of carcasses.
Abstract in English:ABSTRACT This study examined the replacement of maize and soybean meal with cassava chips and alfalfa grazing, respectively. Twelve lactating Anglo-Nubian goats were kept on a Panicum maximum cv. Tobiatã pasture. The experiment was laid out in a Latin square design in which the following diets were tested: ground maize + soybean meal, cassava chips + soybean meal, ground maize + alfalfa grazing, and cassava chips + alfalfa grazing. The evaluated variables were feed intake, daily weight gain, milk yield and composition, and feeding behavior of the goats as well as production costs. Cassava chips and grazed alfalfa influenced the intakes of dry matter, crude protein, neutral detergent fiber, and total digestible nutrients. However, milk yield, body weight, and body score did not change. There was no diet effect on the proportions of protein, solids-not-fat, somatic cell count, or urea nitrogen in the milk. Treatments influenced the levels of fat, lactose, and total solids in milk, with the highest fat levels achieved with diets containing alfalfa. Grazing, rumination, and idle times and time spent interacting with other goats were not influenced by diets. The evaluated feedstuffs improved feed efficiency and reduced production costs. Therefore, cassava chips and alfalfa can replace certain ingredients without impairing the production performance of goats, but rather improving the profit of the producer.
Abstract in English:ABSTRACT This study evaluated the changes in rumen microbiome during the process of age development of farming Guizhou White goats from Southwest China. We conducted high-throughput 16S rRNA gene sequencing to investigate the diversity, structure, and composition of goat rumen microbiota (RM) of 21 goats of different age groups (1, 6, and 12 months). We found that volatile fatty acids (i.e., acetate, propionate, and butyrate) fermented by microbes were found to increase significantly in the six- and one-month-old goats. Results of the genera abundance analysis showed that abundance of eight and seven taxa decreased in six- and one-month-old goats, respectively, compared with that in 12-month-old goats. Additionally, differences in six taxa in six-month-old goats and in one taxon in one-month-old goats were found. In addition, specific gut microbiome was found, which was significantly correlated with rumen fermentation parameters in Guizhou White goats. These results revealed the signature microbiota in RM during various developmental stages in goats raised in Southwest China and can also provide a guiding tool for evaluating rumen health of ruminants worldwide.
Abstract in English:ABSTRACT We examined differences in slaughter performance and meat quality of Honghe yellow cattle of different ages. We randomly selected nine Honghe bulls for slaughter at 12 (12M), 36 (36M), and 60 (60M) months of age. There were significant differences in antemortem live weight, carcass weight, and net weight among the three groups, all of which increased with age. Backfat thickness in 36M (4.77±0.25 mm) and 60M (5.50±0.50 mm) was significantly higher than in 12M (3.00±0.00 mm), and the loin-eye area in 60M (68.02±16.02) was higher than in 12M (27.01±1.89). There was no significant difference in the pH value of the month-old group. Compared with 12M (29.33±4.93%) and 60M (23.87±5.08%), the cooking loss of meat in 36M (36.50±5.07%) was significantly higher; meanwhile, a* value was also the highest in 36M (22.39±1.34), the protein and fat content of muscle in 12M was lower, while the content of meat in 60M was lower. There was no significant difference in muscle ash, Ca, and P contents; the total amino acid and essential amino acid contents of 36M were higher than those of 12M and 60M, and the unsaturated fatty acids of meat in 12M were higher than those in 36M and 60M. The change of age has a certain influence on the slaughter performance and meat quality of Honghe yellow cattle.
Abstract in English:ABSTRACT We investigated the effects of corn grain, finely or coarsely ground, rehydrated and ensiled to 35% moisture in substitution of dry corn grain on performance of beef cattle in the feedlot. Forty non-castrated young Angus crossbred bulls with average age of 13±1.4 months and average initial body weight (BW) of 374±14 kg. The experiment was conducted in blocks by weight, and bulls were randomly assigned into four groups of five animals each in a 2 × 2 factorial scheme. The factors evaluated were particle size (finely and coarsely ground) and two grain sources (dry ground corn and rehydrated corn grain silage). The treatments were diets containing dry corn grain, finely ground (DCF; 1.86 mm); dry corn grain, coarsely ground (DCC; 3.53 mm); rehydrated and ensiled corn grain, finely ground (RCF; 1.86 mm); and rehydrated and ensiled corn grain, coarsely ground (RCC; 3.53 mm). Initial BW, final BW, average daily gain (ADG), feed efficiency, and intake of dry matter (DMI), acid detergent fiber, and metabolizable energy were not affected by treatment. Ensiling corn grain decreased DMI by 10.3% (11.6 vs. 10.4 kg/d for dry and ensiled, respectively) and increased feed efficiency by 13.3% (0.13 vs. 0.15 kg/d for dry and ensiled, respectively), but there was no effect of particle size, grain source, and their interaction on ADG. Effects of particle size and grain source were observed for fecal starch and total tract starch digestion, with evidence that treatments containing rehydrated corn diets showed greater efficiency in the utilization of dietary starch. Animals fed RCF diets showed lower fecal starch losses of 37, 55, and 75% when compared with treatments RCC, DCF, and DCC, respectively. Our results suggested that ensiled rehydrated corn grain improves feed efficiency in substitution of dry corn grain. The finely and coarsely ground of rehydrated and ensiled corn grain increases the digestibility of starch for finishing cattle in feedlot.
Abstract in English:ABSTRACT This study examined the effect of different supplementation strategies for ewes in the last third of gestation, kept on a deferred Brachiaria brizantha cv. Marandu pasture, on their performance and the growth curve of their lambs. A total of 54 ewes, of no defined breed, with an average weight of 41.10±3.10 kg, were used in a completely randomized design, divided into three groups (18 ewes per treatment). In total, 61 lambs were born, 28 females and 33 males, with 3.70±0.55 and 3.68±0.69 kg birth weight, respectively. Treatments were as follows: multiple mixture ad libitum, concentrate supplement at 0.4% live weight (LW), and concentrate supplement at 0.8% LW. Average daily weight gain (ADG, g/animal/day) and total weight gain (TWG, kg/animal) were evaluated in ewes and lambs. Reproductive efficiency indices were measured in the ewes and biometric variables in the lambs. The ADG and TWG of ewes in the last third of gestation were higher in animals supplemented at 0.8% LW. Reproductive efficiency results were superior in ewes supplemented at 0.4% LW. The effect of ewe supplementation on lamb growth curve as estimated by the Gompertz model did not reveal differences between the curves of lambs born to ewes that received supplementation at 0.4 and 0.8% LW. However, supplementing ewes with a multiple mixture induced a reduction in the growth curve parameters of their lambs. The use of concentrated supplementation, at levels of 0.4 and 0.8% of LW, provides greater productive and reproductive performance for ewes and lambs.
Abstract in English:ABSTRACT The objective was to evaluate the inclusion of chitosan (CHI) and technical cashew nut shell liquid (CNSLt) as natural feed additives in cattle diets on nutrient digestibility, ruminal fermentation, and in vitro gas production kinetics. We conducted a completely randomized design with 5×4 factorial arrangement, with 20, 35, 50, 65, and 100% Tifton 85 hay and four additives, monensin (200 mg/kg DM), CNSLt (500 mg/kg DM), CHI (500 mg/kg DM), and CNSLt+CHI (500 mg/kg DM/each). Dry matter (DM) and organic matter (OM) digestibility showed a linear reduction according to forage levels. The highest DM digestibility was observed with CHI on cattle diets. Inclusion of CHI increased DM digestibility. The highest in vitro organic matter and crude protein (CP) digestibilities were observed for CNSLt+CHI. The in vitro dry matter digestibility increased linearly with concentrate in the diet. There was interaction of forage:concentrate ratio and the additives for neutral detergent fiber, acid detergent fiber and hemicellulose digestibility. Chitosan, CNSLt, and CNSLt+CHI promoted the lowest acetate:propionate ratio compared with monensin. Total gas production showed interaction of the forage:concentrate ratio and additives. Lag time was lowest with CNSLt+CHI. Chitosan and CNSLt can be considered alternative fermentation modulators to ionophores by improving nutrient digestibility and increasing ruminal propionate concentrations.
Abstract in English:ABSTRACT The productive traits of beef cattle are orchestrated by their genetics, post-natal environmental conditions, and also by the intrauterine background. Both under- or overnutrition, as specific dietary components, are able to promote persistent effects on the offspring. This occurs because dietary factors act not only affecting the availability of substrates for fetal anabolism and oxidative metabolism, but also as signals that regulate several events toward fetal development. Therefore, this study aimed to summarize the gestational nutrition effects on the offspring performance and meat quality in a long term. Overall, studies have shown that many of these alterations are under the control of epigenetic mechanisms, as DNA methylation, histones modification, and non-coding RNA. The current knowledge has indicated that the fetal programming responses are dependent on the window of fetal development in which the dietary treatment is applied, the intensity of maternal nutritional stimuli, and the treatment application length. Collectively, studies demonstrated that muscle cell hyperplasia is impaired when maternal requirements were not achieved in the second third of gestation, which limits the formation of a greater number of muscle fibers and the offspring growth potential in a long term. Changes in muscle fibers metabolism and in collagen content were also reported as consequence of a dietary perturbation during pregnancy. In contrast, a maternal overnutrition during the late pregnancy has been associated with beneficial responses on meat quality. In summary, ensuring an adequate maternal environment during the fetal development is crucial to enhance the productive responses in beef cattle operations.
Abstract in English:ABSTRACT The main objective of this study was to determine the effects of milking system on growth, reproduction, and milk yield and composition of East Friesian-cross (Tahirova) dairy sheep that were milked in the evening during the suckling period. A total of 43 Tahirova ewes and 58 lambs were used in the present study. One of the groups was milked in the evening (evening milked; EM) before coming together with their lambs, and the other group was not (not milked in the evening; NEM). Morning milking was performed in both groups during the study. Lambs in both groups were individually weaned at the age of 60 days. There was no statistical difference between the lambs’ live weight at weaning in the EM and NEM groups, determined to be 23.46 and 24.11 kg, respectively. Live weight values of lambs were similar in the groups at ages of up to 180 days. The reproductive characteristics of ewe lambs in the EM and NEM groups, having similar growth rates and a similar live weight and body condition in the first estrus stages, were also similar. The return rate and frequency of return were close in both groups of ewe lambs. Milk yield of the NEM group was significantly higher than that of the EM group before and after weaning. However, in groups with similar lactation milk yield and length, the total marketable milk yield was higher in the suckling period of the EM group. The milking system in suckling period of Tahirova ewes does not significantly affect growth, average daily gain, and reproductive characteristics. Milk yield in the NEM group before and after weaning was significantly higher than the EM group, but the total marketable milk yield was higher in the EM group.
Abstract in English:ABSTRACT This study aimed to evaluate the effects of ground or steam-flaked corn and zinc-enriched yeast addition to grower pellet feed on fattening performance, rumen papillae development, and some blood parameters in lambs. For this purpose, thirty-six Kivircik male lambs were selected and divided equally into six groups: basal diet containing pellet feed without different corn form and yeast (control), basal diet 80% + ground corn 20% (PGC), basal diet 80% + steam-flaked corn 20% (PFC), PGC + Zn-enriched yeast (PGCZnY), PFC + Zn-enriched yeast (PFCZnY), and control + Zn-enriched yeast (PZnY). They were fed for 56 days according to the diets mentioned above. At the conclusion of the evaluations in fattening performance, rumen papillae development, and some blood parameters, there were no significant differences in body weight gain, average daily gain, average daily feed intake, and feed efficiency among the experimental groups. In the PGCZnY group, rumen papillae length was found to be higher than the other experimental groups. At the end of the trial (day 0), leukocyte and lymphocyte counts decreased significantly only in the control group compared with the other groups in the present study. Serum blood urea nitrogen (BUN) values, analyzed at the beginning and at the end of the trial, increased significantly in all groups except in the PGCZnY group. Supplementation of Zinc-enriched yeast to ground corn can be used for increasing ruminal papilla length, however decreasing the serum BUN levels in lambs during the fattening period.
Abstract in English:Abstract This study evaluated chemical composition, in situ dry matter degradability (DMD), energy utilization, and amino acid profile of the sandbox seed meal (SSM) obtained from ground seeds of Hura crepitans trees. Two cannulated male Blackbelly sheep (initial weight of 40 kg) were fed a balanced feed ad libitum for 21 days; rumen samples of animals were collected for seven days using the nylon bag technique for degradability. The results were interpreted in reference to incubation times from 0 to 72 h, evaluating degradation kinetics with an exponential model. The SSM showed crude protein and dry matter contents of 251.1 and 931.7 g/kg, respectively. The highest DMD value was recorded from 0 to 3 h with a change rate of 41%, and the energy contained in SSM had a gradual ruminal disappearance with a maximum value of energy utilization of 14.6% after 72 h post-incubation. The most representative amino acids of SSM were glutamic (16.9%), arginine (13.0%), and aspartic (9.7%) acids. The results suggest that SSM has adequate nutritional quality and ruminal DMD for ovine feeding systems.
Abstract in English:ABSTRACT The objective of this trial was to investigate the potential benefits of enzyme and probiotic supplementation on the growth performance, nutrient digestibility, carcass traits, and meat quality of Simmental cattle. Sixty Simmental steers (367.75±4.69 kg) were randomly divided into three groups: control (fed basal diet), BC1 group (fed basal diet and 10 g/d brewer’s yeast and cellulase supplementation per cattle), and BC2 group (fed basal diet and 20 g/d brewer’s yeast and cellulase supplementation per cattle). A 10-d preparation period was followed by a 120-d experimental period. The results showed that the final weight of the BC2 group was greater than that of the control group. Also, feed conversion ratio of the BC2 group was better than that of the control group. Net meat weight increased by 3.86% in the BC2 group compared with the control group. The apparent digestibility of neutral detergent fiber, acid detergent fiber, and crude protein of the BC2 group was greater than that of the control group. Dietary supplementation with brewer’s yeast and cellulase supplementation could improve the growth performance and nutrient digestibility of Simmental cattle.
Abstract in English:ABSTRACT We aimed to evaluate the effects of the addition of oregano (Origanum vulgare) or green tea (Camellia sinensis L.) extracts (separately and associated) on feed intake, milk production, and hematological and antioxidant profiles of dairy cows. For that purpose, 16 Holstein and 16 Holstein-Gyr cows with 526.3±10.2 kg and within the first third of lactation were distributed according to a complete block design with measurements repeated in time. Treatments were control (CON), addition of 0.056% of oregano extract (OR), addition of 0.028% of green tea extract (GT), addition of a mixture of OR and GT extract (0.056% each) in the diet (MIX). Hematological and antioxidant profiles were monitored. Data were subjected to ANOVA, with block, treatment, days, and their interactions considered as fixed effects and animal and the residue as random effects. In Holstein cows, GT increased feed intake and milk yield compared with CON; in Holstein-Gyr crossbred cows, OR showed increased intake and GT increased milk yield compared with CON. Compared with CON, GT and OR decreased eosinophils concentration; OR showed the highest neutrophils concentration and neutrophils to leukocyte ratio. Compared with CON, OR presented increased catalase (CAT) activity, while GT increased the reduced glutathione concentration. The MIX treatment reduced CAT activity compared with OR, presented the lowest concentration of oxidized dichlorofluorescein in the erythrocytes (DCFER) and plasma (DCFPLA), and increased eosinophils concentration compared with GT and OR. Extracts differently affected feed intake and milk yield depending on genetic group. Feeding green tea and oregano extracts separately or associated distinctly affects the antioxidant indicators of lactating dairy cows.