Abstract in English:ABSTRACT The present study was conducted to evaluate the performance, carcass yield, and histomorphometry of the small intestine of broilers fed yeast sugarcane supplemented with enzymatic blend from 22 to 42 days of age. Seven hundred broiler chicks were distributed in a completely randomized design in a factorial design (2x3+1), two levels of the enzyme blend (0 and 200 g/ton), three protein levels (0%, 6% and 12%) and a control diet. The level of 6% yeast showed higher feed intake and weight gain after 33 days. From 22 to 42 days there was no significant effect (p<0.05) to the use of yeast in animal performance, carcass yield and cuts. At 42 days an interaction between the factors for width and crypt depth in the duodenum and jejunum, respectively, was observed. The inclusion of yeast in the diets for broilers from 22 to 42 days did not affect the performance and yield of the carcass. Yeast increased the muscle wall of the jejunum. The use of the enzymatic blend did not influence performance but affected the integrity of the intestinal mucosa.
Abstract in English:ABSTRACT In this study, the effect of evaporated ethyl pyruvate (EP) was evaluated for the decontamination of Salmonella Enteritidis on chicken leg meat as a safe alternative to antimicrobial agent. Also, total aerobic mesophilic bacteria (TAMB), Enterobacteriaceae, Escherichia coli and yeast-mold counts samples were investigated. Subsequently, the samples were injected with 0, 42, 105 and 420 mg evaporated EP/L air to the paper filter attached to the container cover and stored at +4 °C for 10 days. According to the results, 42 mg EP/L concentration did not cause a significant decrease in Salmonella Enteritidis count (p>0.05). However, it was determined that 105 and 420 mg EP/L treatments reduced the number of Salmonella Enteritidis by more than 1 and 2 log, respectively. EP application also significantly influenced the number of TAMB, Enterobacteriaceae and yeast-mold. These results indicate that EP is an effective antimicrobial that could be used to enhance the safety of chicken meat.
Abstract in English:ABSTRACT In this study, the effect of replacement of soybean meal with raw chickpea seeds as a primary protein source in the diet of broiler chicks on physical properties of drumstick muscle (m. gastrocnemius) was examined. One-day-old Ross 308 broilers (n=160) were fed soybean meal (n=80) or raw chickpea seeds (n=80) as a primary protein source for 42 days. Drumstick muscles, after dissection and storage for 24 h at 5°C, were subjected to texture profile analysis to determine changes in the structural and material integrity, and the thermal stability of muscle proteins were assessed on the basis of differential scanning calorimetry measurements. Light meromyosin, heavy meromyosin and sarcoplasmic proteins in the meat samples of broilers fed raw chickpea seeds were characterized by higher thermal stability as the higher denaturation temperatures were observed. In addition, the calorimetric enthalpy of denaturation of light meromyosin was significantly higher in the muscles of broiler fed raw chickpea seeds, while higher enthalpy of denaturation of actin was determined in those fed soybean meal. Muscle weight, hardness, and the other evaluated textural traits, did not differ between treatments. In summary, dietary protein source affected only thermal stability of muscle proteins; however, the physiological consequences of these alterations are yet to be determined. This study also showed that thermal analysis can be a useful tool for analyzing the effect of nutrition on the development and structural changes in the muscle tissues of poultry.
Abstract in English:ABSTRACT Corn is the main energy feed used in broiler chickens rations in most countries. In the literature, there are indications that high density corn segregated in densimetric table contains higher value of metabolizable energy than the corresponding fraction of low density, but the reasons are not clear. This study was conducted to determine the metabolizable energy of different types of corn, segregated in densimetric table, for poultry. The corn types were selected by the texture of grain (flint, semi-dent and dent) and were planted in the same area. Semi-dent grain corn was used as standard, and the flint and dent grains were segregated in a densimetric table to separate 25% of the total as high density and 25% as low density. The flint, semi-dent and dent corn and the high and low density fractions of flint and dent corn were used in a metabolism assay with broiler chickens from 20 to 29 days of age, with 9 replicates, to determine the Nitrogen-corrected apparent metabolizable energy (MEn). The density of the different types of corn, measured as hectoliter weight, varied from 683 to 768 g/L for dent corn and from 778 to 802 g/L for the flint corn; the density of the unsegregated semi-dent corn was intermediate. MEn ranged from 3.109 to 3.194 kcal/g for dent corn and from 3.141 to 3.211 kcal/g for flint corn. MEn of the high density dent corn, 3.194 kcal/g, was higher (p<0.05) than that of the low density fraction, 3.109 kcal/g. Segregation of flint corn did not result in fractions with contrasting MEn values. For dent corn, segregation in densimetric table was effective, resulting in a fraction with improved MEn for chickens.
Abstract in English:ABSTRACT The aim of this study was to evaluate diets supplemented with probiotic (Bacillus amyloliquefaciens) and organic acids (lactic, acetic and butyric acid) in attempt to replace the antibiotics and anticoccidial (avilamycin + sodium monensin) growth promoters on performance and economic viability of broilers challenged by Eimeria acervulina, E. maxima and E. tenella. A total of 900 male Cobb® chickens, with a mean weight of 39.90g, were distributed in a completely randomized design in a 2 × 2 + 1 factorial arrangement: supplementation or not of probiotic and organic acids and a treatment with inclusion of antibiotics, comprising five treatments with six replicates. For the studied performance variables, there was no effect of the isolated additives and no interaction between them (p>0.05). Only the antibiotics promoted better results for weight gain (WG), feed intake (FI) and feed conversion rate (FCR). Therefore, the use of organic acids and probiotic, isolated or associated, provided lower performance to those receiving antibiotics, not improving the performance of chickens under the imposed challenge conditions. The highest revenues were generated with the use of antibiotics, providing greater profits.
Abstract in English:ABSTRACT This paper describes the epidemiological, clinical and pathological aspects of an avian encephalomyelitis (AE) outbreak in commercial laying hens in Northeastern Brazil. The disease affected 23,409 layers (from day one until 100 weeks) leading to mortality of 16.5% (5,049/30,600) of the flock. Twenty laying hens were clinically examined, and blood samples were collected and tested by Enzyme-Linked Immunosorbent Assay (ELISA). Five laying hens with neurological signs were necropsied and samples of the brain, cerebellum, spinal cord, sciatic nerve, heart, ceca tonsils, proventriculus and liver were collected, fixed in formalin buffered solution and processed according to routine methods for histological examination. Clinical signs were observed in approximately 60% of the chicken flock and included depression, ataxia, head and neck tremors, head tilt, motor incoordination and corneal opacity and of lens. All laying hens presented seroconversion for AE, with a geometric mean titer (GMT) of 6,854 and CV of 9.6%. At necropsy, there were bilateral opacity of the cornea and lens and the blood vessels of the cerebral cortex were hyperemic. The main microscopic lesions in the central nervous system consisted of red and shrunken neurons in the cerebral cortex, cerebellum and spinal cord. Significant areas of gliosis were observed in the cerebral cortex and in the molecular layer of the cerebellum. Hyperplasia of the proventricular lymphoid tissue and the ceca tonsils were observed with different degrees of intensity. In Northeastern Brazil, there haven’t been previous reports of AE in commercial laying hens and this outbreak possibly occurred by inefficient immunization of laying breeders at the genetic supply company.
Abstract in English:ABSTRACT The aim of this study was to determine the LD30 values of the essential oils of Origanum minutiflorum He Schwarz-PH Davis (OM) and Juniperus excelca by Bieb.subsp. Excel (JE) in vivo investigation on the effects of malondialdehyde (MDA), vitamin C and some biochemical parameters. In this, study the essential oils of OM and JE plants were used. LD50 values of the essential oils were determined by using rats. OM (n=10), JE (n=10), carvacrol (n=10) which dissolve in olive oil were used as experimental group and as control group saline (SF) (n=8) and solvent Olive oil (n=10) were used and applied intraperitoneal on rats for 12 days in LD30 dosages. In the end of 12 days, Vit-C, malondialdehyde (MDA) and routine biochemical analyses were studied on their heart bloods. The difference in the levels of MDA and Vit-C was found significant among the groups (p<0.005). When the biochemical parameters of the groups were compared, all differences in all test were found significant (p<0.005) except for creatinine (p>0.005). When the values are put to paired comparison, the differences between groups were found statistically significant (p<0.005).OM and JE has led to significant changes in all lipid peroxidation and enzyme levels.
Abstract in English:ABSTRACT Poultry rations are composed mainly of conventional cereal grains and proteins. Using non-conventional agro-industrial by-products may reduce the cost of production and thereby improve productivity. A study was conducted to evaluate the effect of dietary brewery spent grain inclusion on egg laying performance, quality parameters of bovans brown and profitability of the rations. A total of 200 pullets with similar body weight and age were randomly distributed to five treatments with four replications. The treatments were brewery spent grain (BSG) inclusion of 0, 10, 20, 30 and 40% levels for T1, T2, T3, T4 and T5, respectively. The CP and ME contents of treatment rations were 16.54-17.04% and 2871-2903 kcal/kg DM, respectively. Inclusion of the BSG in the layers ration did not affect dry matter intake, feed conversion efficiency and hen-day egg production (58.79, 57, 56.11, 55.11 and 54.13% (SEM=0.92)). Likewise, the inclusion of the BSG in the diets did not affect (albumen, yolk, shell) quality. However, feed cost decreased with the increasing level of the BSG in the rations because of its lower purchasing price. To conclude, a 40% inclusion of BSG in the diet of layers does not affect the production and the quality of the eggs and it can be economically profitable.
Abstract in English:ABSTRACT The feasibility of Laminaria japonica powder (LJP) combined with cecropin as a dietary supplement to enhance broiler growth performance and immune function was evaluated in this study. In total, 648 one-day-old Arbor Acres broiler chicks were randomly distributed into nine numerically-equal treatment groups: T1 (control group; fed a basal diet); T2 (fed the basal diet supplemented with 1% LJP);T3 (fed the basal diet supplemented with 300mg cecropin/kg); and T4,T5,T6,T7,T8 and T9, individually fed with the dietary supplemented with varying levels of LJP and cecropin). Compared with the control, dietary of LJP or cecropin supplementation slightly improved feed conversion ratio (FCR). However, the dietary supplementation of LJP combined with cecropin significantly improved broiler growth performance during the periods of 1-21,21-42, and 1-42 days (p<0.05).The dietary supplementation of 3% LJP combined with 300 mg/kg cecropin significantly increased FCR, and serum Newcastle disease antibody titers and lymphocyte numbers during the periods of 1-21, 21-42, and 1-42 days (p<0.05). Cecal microorganisms were cultivated and the number of Escherichia coli and Lactobacillus colonies were counted. The dietary supplementation of LJP combined with cecropin remarkably inhibited E. coli growth and increased Lactobacillus growth. The results of this study demonstrate the feasibility of using LJP and cecropin as feed supplement for improving the growth performance and enhancing the immune function of broilers.
Abstract in English:ABSTRACT The objective of this study was to identify the species and characterize the genetic relationships among mycoplasma isolates from commercial layer hen flocks using 16S-23S rDNA intergenic spacer region (IGSR) sequencing. Twenty-one isolates were obtained from samples collected from commercial layer flocks in four Brazilian states: São Paulo, Minas Gerais, Rio de Janeiro and Espírito Santo. The isolates were recovered from the São Paulo, Rio de Janeiro and Espírito Santo states. Eleven isolates were originated from tracheal swabs, five from shell gland swabs and five from ovary fragment collection. The 16S-23S rDNA IGSR of isolates were amplified by PCR, and the obtained products were subsequently sequenced. The consensus of each isolate was compared to the available sequences using Nucleotide BLAST® to determine the mycoplasma species. A phylogenetic analysis of the Mycoplasma gallisepticum (MG) sequences was performed. Pairwise analyses showed homologies of 99% to 100% with the previously characterized sequences listed in GenBank®. Four Mycoplasma gallinaceum were isolated from three flocks and seven M. pullorum isolates were obtained from a single flock. The other 10 isolates were all identified as MG and were obtained from four flocks. The 16S-23S rDNA IGSR sequencing was a good method to identify Mycoplasma species isolated from field samples, providing fast and reliable results at relatively low costs. The results were also satisfactory for the single-locus sequence typing of MG isolates.
Abstract in English:ABSTRACT There is increasing evidence that bone morphogenetic protein 6 (BMP6) plays critical roles in regulating various stages of ovarian follicle development in mammals. However, the mechanisms of regulation of BMP6 in the chicken ovary remain unclear. In this study, mRNA and protein expression level of BMP6 in chicken ovarian follicles at different development stages were determined by qRT-PCR and western blot separately. Different concentrations of BMP6 protein and FSH were added to the culture medium, and the effects to proliferation of granulose cells were detected, further effect on expression pattern of progesterone synthesis associated genes were also analyzed by qRT-PCR and Western blotting and the secretion of progesterone was detected by ELISA. The results showed that mRNA and protein expression level of BMP6 increased significantly in the follicle with the development of follicle (p<0.05) and reached a peak at F1 follicle. Adding concentration of 50ng/ml and 100ng/ml of BMP6 protein promoted significantly the proliferation of granulosa cells (p<0.05), as well as up-regulated the expression of Steroid hormone synthesis acute regulatory protein (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) genes in mRNA and protein level. Meanwhile, the secretion of progesterone was significantly higher in the group that added BMP6 and FSH separately than blank control group (p<0.05) and reached a peak in the group that both added BMP6 and FSH. Collectively, these findings highlight that BMP6 is associated with proliferation of follicular cells and the synthesis of progesterone, which indicated that it took an important role in the follicular development of chicken.
Abstract in English:ABSTRACT This study analyzed the effect of job rotation on the risk of developing UL-WMSDs in a poultry slaughterhouse with 1,200 workers. Three organizational settings were evaluated (“without job rotation”, “with job rotation - tasks >1h” and “with job rotation - tasks <1h”) using the OCRA Checklist method and the fulfillment of requirements for the implementation of rotations established by the Brazilian Regulatory Standard NR-36. The OCRA score of the right upper limbs (16.5±5.7) were significantly higher (p<0.001) relative to the left upper limbs (15.0±5.6). The average scores on all three organizational conditions presented moderate risk. There was a significant difference between the scores of the conditions “without job rotation” and “with job rotation - tasks <1h” (p=0.011), as well as “without job rotation” and “with job rotation - tasks >1h” (p<0.001). Thus, the results of the risk using the OCRA Checklist method showed the inefficiency of the realization of rotations >1h and <1h compared to not carrying out job rotation for the reduction of the UL-WMSDs risk. In relation to NR-36 requirements, it was found that alternating sitting and standing posture, postural requirements reduction and monotony were met by most sectors. Finally, it was difficult implementing efficient rotations due to particularities of work in the slaughterhouses such as: tasks with similar musculoskeletal requirements, pace imposed by machines, inability to perform rotations between different sectors (health and occupational constraints), the predominance of tasks with moderate and high risks, hindering the distribution of risks between the tasks of the rotation.
Abstract in English:ABSTRACT Trade liberalization during the last decades has increased among nations as a result of decreased tariffs. However, during the same period, market agents have created new protection measures to replace such mechanisms in an attempt to promote the domestic economic stability of countries, while expanding and ensuring the trade between nations. Considering that Brazil is the second largest broiler producer and chicken-meat exporter worldwide, the present study proposed to analyze the main barriers imposed on Brazilian chicken meat imports by the ten major importing countries. This is a documentary research with primary and secondary data, of a descriptive-exploratory nature, under a qualitative approach. Semi-structured questionnaires including open- and close-ended questions were sent using Survey Monkey software to the Brazilian Association of Animal Protein. The study revealed that technical requirements are those most often imposed by the importing countries, indicating their concern about the safety, quality, and origin of the imported good. Commercial requirements do not constitute a problem for the growth of Brazilian chicken meat exports; however, the requirements made by some countries preclude the exports.
Abstract in English:ABSTRACT The 7-week feeding trial evaluated the effect of 2% grapeseed meal used as natural antioxidant in the diets for slow-growing Hubbard broiler chicks, aged 14 days. The chicks were weighed individually and assigned to two groups (C and E), with 40 chicks per group, housed under conditions of temperature, humidity and light regimen according to the hybrid management guide. The basal ingredients of the conventional diet were corn, wheat, gluten, soybean meal and 2% flaxseed meal, which is rich in polyunsaturated fatty acids. Compared to the control formulation, the experimental formulation included 2% grapeseed meal, both in the growing and finishing stages. The broilers had free access to feed and water. In the end of the feeding trial, blood samples were collected for serum biochemical determinations and six broilers per group were slaughtered and samples of breast and thigh meat were collected. The meat samples were assayed for the basic chemical composition, fatty acids profile and cholesterol content using standardized methods. The content of total polyunsaturated fatty acids (PUFAs) was significantly higher (p<0.05) in breast samples, while cholesterol content was significantly lower (p<0.05) in thigh samples from E group, compared to C. Blood glucose, cholesterol and triglyceride levels were significantly lower (p<0.05) in group E than in group C. The study showed that the grapeseed meal used as natural antioxidant in broiler diets enriched in polyunsaturated fatty acids given to Hubbard broilers had beneficial effects on broiler meat quality and on the metabolic profile of the blood plasma.
Abstract in English:ABSTRACT For a long time, it has been said that eggshell quality decreases as eggs increase in size, but this increase is seen as the breeder age advances. Therefore, the present study aimed to evaluate the age and egg weight effect on Cobb 500 broiler breeders on eggshell quality. The quality measures tested were eggshell and mineral matter percentage, eggshell surface, shape and eggshell index, eggshell and membrane thickness and specific gravity. Eggs from 27, 31, 36, 40, 46, 48, 53, 58 and 63 week-old breeders were classified as eggs with a constant weight ranging from 63.8 ± 0.2; and eggs with increasing weight, according to age, being: 55.8g; 60g; 62.2g; 64.2g; 65.2g, 66.6g, 68.1g, 69.9g and 72.5g, respectively. The eggs weight did not influence the eggshell percentage and the specific gravity in seven of the nine tested ages, while for mineral matter in six of the nine studied ages. The shape and shell index, shell and membrane thickness are characteristics independent of egg weight. As the Cobb 500 broiler breeder age advanced, the mineral matter concentration and specific gravity maintained constant, the membrane thickness (R2>70) reduced, and other studied variables were influenced in the same way for both treatments. Thus, the eggshell quality decrease with the advancing age cannot be attributed solely to the increase of egg weight with consequent increase in the eggshell volume and the surface, but there are also age-related factors.
Abstract in English:ABSTRACT Homeobox B9 (HOXB9) gene has been demonstrated to be associated with melanogenesis in chicken plumage by high-throughput RNA sequencing. In this study, we cloned and characterised HOXB9 in black-boned chickens. Two alternative splice variants (HOXB9-1 and HOXB9-2) were identiﬁed in chicken feather bulbs. Expression analysis of HOXB9 in 11 different chicken tissues by RT-PCR indicated that the two transcripts were only expressed in the kidney, abdominal fat, feather bulbs, skin, and small intestine. No HOXB9-1 or HOXB9-2 transcripts were detected in the breast muscle or the ovary. The two HOXB9 variants were expressed at significantly different levels in black feather bulbs and white feather bulbs (p<0.01), and in black skin compared with white skin (p<0.01). The results indicate that HOXB9-1 and HOXB9-2 may be involved in melanin formation in the plumage and skin. The expression of HOXB9-2 was higher in white than in black muscles (p<0.05), HOXB9-2 may play a role in muscle melanogenesis. Our results suggest that HOXB9, which is partially regulated by alternative splicing, may be involved in the process of melanogenesis in the black-boned chicken.
Abstract in English:ABSTRACT Brazilian processing plants have identified the so-calledspaghetti breast myopathy characterized by muscular dystrophy of unknown etiology. This study aimed at estimating the incidence of spaghetti breast myopathyin broilers from three commercial genetic strains (Ross, Cobb, Hubbard) reared in two different housing systems (DH, Dark house, and TS, Tunnel system), presenting different controlled ventilation systems and light availability. Breast meat samples (n=5,580) were collected and macroscopically evaluated for spaghetti breast myopathy according to a 0-2 scale, as 0 = normal, 1 = intermediate or moderate, and 2 = severe. A higher number of broilers reared in DH presented normal breasts and moderate myopathy relative to TS-reared birds. Ross broilers presented a higher incidence of normal breasts compared with Cobb and Hubbard broilers. The risk of presenting spaghetti breast myopathy was higher in broilers reared in DH than those in reared in TS, indicating that the exposure to DH environmental conditions may increase the chance of myopathy incidence. Broilers reared in dark houses presented 26% higher chance and 13% higher risk of showing spaghetti-breast myopathy the than those reared in tunnel-ventilated systems.
Abstract in English:ABSTRACT Heat stress induces oxidative stress, and reduces body antioxidant metabolite levels, which can affect poultry production performance. Dietary antioxidants protect birds against the adverse effects of heat stress. The effects of increasing concentrations of dietary curcumin on the antioxidant parameters of layers maintained under high-temperature conditions for nine weeks were evaluated. Roman laying hens (n = 336, 22 weeks old, 1420 g BW) were divided into three treatment groups. The first group served as a thermoneutral control (kept at 25 ± 1 °C). The second group was exposed to high temperatures (32 ± 1 °C, 6 h/d), given a basal diet. The third group was further divided into five treatment groups (100, 150, 200, 250, 300 mg/kg Curcumin) fed a basal diet (treatments H1, H2, H3, H4, H5) under high temperatures conditions (32 ± 1 °C, 6 hours/day). As a result of this study, total superoxide dismutase activity was significantly higher in H2 and H3 groups, and total antioxidant capacity was higher in H2, H3, and H5 groups. Catalase and glutathione peroxidase activity was significantly higher in the H3 group. Malondialdehyde concentration was lowered in curcumin supplemented hens compared with control groups hens. Laying hens in all curcumin treatment groups had slightly higher activities of CAT, SOD, GSH-Px, and T-AOC in the liver, heart, and lungs, compared with heat stressed control group. It was concluded that dietary curcumin given to laying hens under heat stress may enhance their antioxidant status, and alleviate the detrimental effects of stressful environmental conditions.
Abstract in English:ABSTRACT The present study aimed to determine ideal levels of available phosphorus for muscovy ducks in housing. Two hundred and forty muscovy ducks of creole lineage were used, distributed in boxes with water and food ad libitum. The experimental design was completely randomized with treatments consisting of six nutritional plans that included the initial, growth and termination phases and differed in relation to available phosphorus levels, and four replicates of 10 muscovy ducks each. The birds had weekly performance evaluations, and after 90 days, eight birds (four males and four females) in each treatment were slaughtered for evaluation of carcass traits. Data collected were subjected to Tukey test at 5% of significance. Differences were not observed (p>0.05) in performance. Higher available phosphorus levels presented a positive influence (p<0.05) on carcass. Results presented differences (p<0.05) among sexes for carcass development and commercial cuts, with better feed efficiency of males than females in same period. For mineral composition, differences (p<0.05) were observed to calcium (%), phosphorus (%) and Ca:Pratio. The present study indicates that nutritional plan 2 (initial = 0.60%; growth = 0.55% and termination = 0.50%) presented ideal nutritional requirement of available phosphorus for muscovy ducks in housing, with better carcass development and mineral deposition on bones.
Abstract in English:ABSTRACT The aim of this project was to investigate the effect of dietary inclusion of sodium bicarbonate (NaHCO3) on nutrient digestibility and immune response of caged layers during summer when the temperature exceeds 40 ˚C. For immune response trial, White Leghorn layers (n=160; 24 weeks old) were purchased from a poultry farm and were divided into five treatment/diets groups (4 replicate/treatment). Diet A, was without NaHCO3 and served as control whereas, diets B, C, D, and E contained 0.5, 1.0, 1.5 and 2.0% NaHCO3, respectively. All these birds were vaccinated against Newcastle disease (ND) virus at the start of the experiment and thereafter with one-month intervals. Blood samples were collected from two birds/replicate at 10 days post vaccination each time to check antibody titer against ND virus. For digestibility trial, fecal samples were collected (6 layers/treatment group) at the start of the 37th week of age for two days, at 3 hours interval. Results revealed that immune response against ND virus 10 days post vaccination after 1st, 2nd and 3rd month was significantly (p<0.05) higher in layer birds fed diets containing NaHCO3. Digestibility of dry matter (DM), crude protein (CP), crude fiber (CF), ether extract (EE) and absorption of minerals were also found to be significantly (p<0.05) higher in groups treated with NaHCO3 and the birds fed diet containing 1% NaHCO3 showed the best results. In general, results revealed that 1% supplementation of NaHCO3 in layers’ diet have a beneficial impact in terms of immunity and diet digestibility.
Abstract in English:ABSTRACT A digestibility assay was conducted in order to determine the digestibility coefficients (DC) of amino acids of feed ingredients in cecectomized adult roosters. In total 48 cecectomized adult roosters were used to assess the coefficient of digestibility of 7 ingredients: corn, soybean meal, soybean concentrate, corn gluten meal, wheat bran, peanut meal, and feather meal. Each ingredient was replicated six times and a group of 6 rooster was used to measure endogenous amino acid losses. After 48 hours of fasting, the roosters were tube fed 20g of ingredients tested twice during a day. At 12 hour-intervals excreta and endogenous losses were collected and immediately freeze-dried for further chemical analysis. At the end of the assay, excreta were weighed and samples of ingredients, excreta, and endogenous losses were pooled and analysed for dry matter, nitrogen and amino acid content. The coefficients of indispensable amino acids for the most feed ingredients assessed in the current research were similar to published literature like AMINODat®5.0 and the 4th edition of the Brazilian Tables for Poultry and Swine, except feather meal, in which only digestible Trp and Thr content were similar to literature. Particularly, the coefficients for some amino acids like Arg and Gly exhibited large discrepancies from literature in almost all the feed ingredients assessed herein. In general, using cecectomized adult roosters proved to be a reliable technique to assess the digestibility of feed ingredients used in poultry diets.
Abstract in English:ABSTRACT The present study aimed at evaluating the effect of housing system on the live performance, egg quality, and hatching traits of three dual-purpose chicken genotypes. In total, 180 birds, comprising 48 pullets and 12 cockerels from each of three genotypes, were evaluated during the production phase (27-46 weeks). For this, 144 pullets and 36 cockerels were randomly picked from 18 treatment block groups were shifted to breeding coops, allotting 4 pullets to one cockerel. A completely randomized complete block design (RCBD) was employed. Three genotypes, purebred Naked Neck (NN) and two crosses Rhode Island Red × Naked Neck (RIR × NN = RNN) and Black Australorp × Naked Neck (BAL × NN = BNN), were compared. Intensive system (p<0.0001) and BNN hens (p<0.0001) were heavier on week 26 and 46. Higher egg production (p<0.0001) was obtained in the intensive system and in BNN hens (p<0.0001). Hens maintained in the intensive systems produced heavier eggs and higher egg mass (p<0.0001), and RNN and BNN hens laid heavier eggs (p<0.0001) while higher egg mass (p<0.0001) was found in BNN hens. Higher egg shape index (initial, p=0.0002), egg surface area (initial, p<0.0001; final, p<0.0001), egg volume (initial, p<0.0001; final, p<0.0001) and Haugh unit score (initial, p=0.0002; final, p=<0.0001) were obtained in RNN and BNN hens. At the end of the experiment (46 weeks), higher yolk index (p=0.0004) was found in RNN and BNN eggs, and thicker eggshells (p<0.0001) in RNN eggs. Higher egg hatchability was obtained in the free-range system (p<0.0001) and in the RNN genotype (p<0.0001). The highest fertility rates were detected in the free-range system (p<0.0001), and in the RNN and BNN genotypes (p<0.0001). The lowest infertile egg rates were observed in the free-range system (p<0.0001) and in RNN and BNN genotypes (p<0.0001). The lowest dead-in-shell rate was calculated for the free-range system (p=0.0456). In conclusion, free-range and semi-intensive system largely influence productive performance, egg quality and hatching traits. Regarding genotypes, RNN and BNN crossbred hens perform better than NN purebreds.
Abstract in English:ABSTRACT This study conducted an in-depth investigation on the development of GABAergic neurons and their receptors in HPG axis-related target organs of Wenchang chicks under heat stress. One-day-old healthy Wenchang chicks were randomly divided into control (CK) and heat stress (HS) groups. Chicks in the HS group were placed in a 40±0.5°C climatic chamber for HS treatment from 13:00 to 15:00 daily. By immunohistochemistry and Western blotting, GABA and GABAA receptor (GABAAR) expression in the hypothalamus of the HS group was significantly higher (p<0.05), but GABAB receptor (GABABR) expression was significantly lower than that of the CK group (p<0.05). Expression of GABA and its two receptors in the pituitary tissues of the HS group was significantly lower than in the CK group (p<0.05). Expression of GABA and GABABR in ovaries in the HS group was significantly higher, but expression of GABAAR in the testes of the HS group was lower than that of the CK group (p<0.05). In the male chicks, expression of GABA and its two receptors in the hypothalamus, pituitary, and testicular tissues of the HS group was significantly higher than that of the CK group (p<0.05). Western blotting showed that the GABAAR and GABABR expression of the HS group was significantly higher than that of the CK group at 3 and 5 weeks of age. Thus, HS caused GABAergic nervous system disorder in the HPG axis of Wenchang chicks and seriously hindered the normal development of GABAergic neurons in chicks, leading to the disorder of the expression of GABA and its receptors in tissues.
Abstract in English:ABSTRACT The morphometric parameters of erythrocytes in Mandarin ducks- Aix galericulata have never been subjected to study even though this species is common in aviculture. The aim of this study is to investigate the morphometric parameters of erythrocytes in juvenile Mandarin ducks. A total of 1500 erythrocytes obtained from thirty Mandarin ducks were analysed. The smears of the peripheral blood were stained using Diff-Quik® stain method, and the length and width of erythrocytes were measured using ImageJ program. The average length of the measured erythrocytes was 11.879 µm. The maximal measured length of the erythrocytes was 16.049 µm, and the minimal measured length was 5.668 µm. The average width of the measured erythrocytes was 6.160 µm. The maximal measured width of the erythrocytes was 10.115 µm and the minimal measured width was 3.750 µm. In conclusion, knowing morphometric parameters of Mandarin duck erythrocytes is the first step in evaluation process of erythrocytes’ functional state and health condition of an individual.
Abstract in English:ABSTRACT Chickens have a great participation in meat and egg production. The anatomical scientific data of poultry is important to support the recent researches either for illustrations in academic studies or clinically in diagnosis and treatment of some poultry nutritional diseases. The current investigation was performed on twenty broiler chickens of both sexes. The chickens were anaesthetized, slaughtered then the venous system was flushed with a normal saline to anatomically investigate the distribution of hepatic portal veins both intra and extrahepatic, as well as the hepatic venous and biliary duct systems. The fowl had two hepatic portal veins draining the gastrointestinal tract with its associated organs as spleen and pancreas. The left hepatic portal vein was small, restricted to a limited portion of left hepatic lobe and had been constituted by five main venous tributaries draining the proventriculus, gizzard and pylorus, while the right hepatic portal vein was the largest, receiving the proventriculosplenic, gastropancreaticoduodenal and common mesenteric veins then piercing the right hepatic lobe to be distributed in both hepatic segments through right and left divisions. The fowl has two hepatic portal veins differed in size and distribution. A characteristic imaginary trapezoid shape was formed by some tributaries draining the caudoventral part of the gizzard. There are three ileocecal veins; cranial, caudal and the ileocecal tributary of the cranial mesenteric vein. The wall of gall bladder and the common hepatoenteric duct was characterized by the presence of well-defined longitudinal folds or striations.
Abstract in English:ABSTRACT Thioredoxin reductases (TrxRs) are selenocysteine-containing flavoenzymes that reduce Trxin NADPH-dependent manner. In the view of the direct vital role of TrxR in a wide range of biochemical and physiological processes, methods to inhibit this enzyme are clinically important. TrxR has recently emerged as a new candidate in anticancer drug investigations because of overexpression in tumorous cells. In this study, TrxR from chick liver was purified 94.6-fold with a yield of 4.86% and a specific activity of 0.19 EU/mg. KM and Vmax values of TrxR for DTNB were calculated as 0.9 mM and 0,03 EU/mL, respectively. Then, the effects of the flavonoids hesperidin, naringenin, chlorogenic acid, ferulic acid, naringin, 3,4-dihydoxybenzoic acid, and ellagic acid on the enzyme activity were evaluated under in-vitro conditions. Ellagic acid showed the strongest inhibitory activity on TrxR with a IC50 value of 18 µM, followed by naringenin and chlorogenic acid with IC50 values of 46.7 µM and 75.8 µM, respectively. Our results showed that flavonoids as natural products are potential inhibitors of TrxRs and the flavonoid content in animal diets may alter metabolic pathways by influencing TrxR activity.
Abstract in English:ABSTRACT In this study, the effects of the supplementation of natural and synthetic antioxidant additives in layer diets on egg weight loss, yolk lipid peroxidation (TBARS values) and fatty acid composition of eggs stored at different temperatures and duration were evaluated. In total, 112 48- weeks-old Bovans White layers were randomly allotted to four dietary treatments with four replicates of seven birds each. The treatments consisted of a control diet, containing no additives, and diets with the inclusion of 200 mg synthetic vitamin E/kg, 1000 mg thyme extract/kg and 1000 mg rosemary extract/kg. Dietary treatments did not influence (p>0.05) relative weight loss of eggs stored for 14, 28, and 56 days, except for those from rosemary-fed hens stored at room temperature on d 42, which were significantly lighter than the eggs from vitamin E- and thyme-fed hens (p<0.001). Relative egg weight loss was significantly higher (p<0.001) when stored at room temperature than under refrigeration, independently of storage time. In eggs stored at room temperature, yolk TBARS values were significantly lower (p<0.001) in the eggs of vitamin E-fed hens, whereas no influence (p>0.05) of dietary treatment on yolk TBARS values were detected in refrigerated eggs. The inclusion of the synthetic and both natural antioxidants in layer diets significantly reduced stearic acid (C18: 0) level in the egg yolk. In addition, only natural antioxidants significantly increased yolk levels of palmitoleic acid (C16: 1) and vaccenic acid (C18: 1n7). The results of the present study showed that adequate storage temperature was more effective in improving egg shelf life than feeding layers synthetic or natural antioxidant additives. However, the positive effects of the evaluated natural antioxidants on yolk fatty acid composition suggest their supplementation to layer diets may provide health benefits to the consumer.
Abstract in English:ABSTRACT The present study was conducted to evaluate the effects of supplementation of garlic, ginger in the diets of broiler chickens and assessment in terms of feed intake, growth performance and economics of feeding. The results showed that groups supplemented with 0.5% garlic powder and 0.5% ginger powder has shown significant effects on body weight as compared to the control group at day 28. Groups supplemented with 0.5% garlic powder and 0.5% ginger powder show significant increase in body weight than the groups supplemented with 0.25% garlic powder and 0.25% ginger powder. Between different supplemented groups, villus length and width of duodenum and jejunum of birds served with 0.5% garlic powder and 0.5% ginger powder is significantly higher than the villus length and width of birds supplemented with 0.25% garlic and 0.25% ginger powder. Between different supplemented groups, villus length of ileum of the group supplemented with 0.5% garlic powder is significantly (p<0.05) lower than the villus length of the groups supplemented with 0.25% garlic powder and 0.25% ginger powder.
Abstract in English:ABSTRACT Antimicrobial resistance is a serious public health problem and Salmonella spp. is highly resistant to antimicrobial agents. Biofilms are important in the food industry due to their formation on products, utensils, and surfaces and the difficulty in their removal. The objective of this study was to assess extended spectrum beta-lactamase (ESBL) production, antimicrobial resistance, and biofilm production of Salmonella isolated from poultry slaughterhouses. Antimicrobial susceptibility was assessed by the disk diffusion assay and ESBL by double diffusion disk assay using the beta-lactamase inhibitor (amoxicillin+clavulanate). The antimicrobials tested were: ampicillin, amoxicillin+clavulanate, aztreonam, ceftazidime, cefotaxime, chloramphenicol, gentamicin, enrofloxacin, sulfonamide, and tetracycline. Serovars Infantis, Panamá, and Tennessee were found to produce ESBL. All serovars were sensitive to tetracycline, and S. Brandenburg was sensitive to all drugs tested. Serovars Panamá, Anatum, Infantis, and Schwarzengrund were moderate biofilm producers at 3 ºC and 9 ºC±1 ºC, respectively, showing possible adaptation of these serovars to these temperatures. Antimicrobials should be used with caution because of the levels of resistance observed and because of ESBL production, and hygiene and sanitary measures should be enhanced to minimize the adhesion of biofilm-forming Salmonella serovars at refrigeration temperatures.
Abstract in English:ABSTRAT Arthritis implies inflammation of the intra-articular structures and is one of the causes of condemnation in broilers. The disease is associated with infectious agents such as Staphylococcus aureus, which may pose a potential public health risk. This work was conducted with the objective to determine the occurrence of arthritis in broiler chickens, predominantly of bacterial staphylococcal origin and if there is a difference between the degrees of injury regarding the presence of the bacterium and the histological lesion. Sixty samples of chickens diagnosed with arthritis by Federal Inspection Service from commercial slaughterhouse were collected according to their severity (of mild and severe degree) and submitted to bacteriological and histopathological analysis. There was bacterial growth of Staphylococcus aureus in 3.3% of the samples classified as mild degree in 10% of the samples classified as severe grade of lesion (p=0,29). For histopathological evaluation, 16.67% and 70% of the samples presented inflammatory infiltrate in mild and severe degrees, respectively (p=0,0001). Mild degree arthritis is related to non-infectious lesions in their higher prevalence while severe-grade arthritis has infectious causes. The condemnation criteria were efficient since S. aureus could be present regardless of the degree of the lesion diagnosed in arthritis.