Resumo em Inglês:

ABSTRACT This study aimed at assessing the effect of pelleted and expanded maize-based feeds prepared with different moisture levels (ML, 0.8 and 1.6%) particle size (PS, 650 and 850µ) of ingredients on metabolizable energy, ileal digestibility of amino acids and broiler performance. A total of 720 one-day-old male broiler chicks of the Cobb strain were used. The experiment was performed over a period of 40d (days) and birds received water and feed ad libitum. From 10 to 13d higher AMEn values were obtained for birds fed expanded feeds with 1.6% ML and 850µ PS. Higher values AMEn were encountered when adding 0.8% ML in pellet feeds with 850µ or 1.6%ML/650µ PS. Expanded and pelleted diets with 1.6% ML (independent of PS, 650 or 850µ) presented higher amino acid digestibility. For diets with 0.8% of ML, better result for the digestibility of amino acids were obtained with PS 650µ for expanded and 850µ for pelleted diets. Higher weight gain was observed in broilers fed diets with 1.6% moisture at 21 and 40d. Feed conversion was improved by adding 1.6% ML only at 21d. Regarding carcass characteristics, expanded diets combined with PS of 650µ led to a higher accumulation of abdominal fat. The birds fed expanded diets at 1.6% moisture had higher breast yields. We concluded that to increase the use of nutrients, EMAn and broiler performance, it is recommended that pelleted diets be prepared with the addition of 1.6% water to the mixer and a particle size of 850µ.

Resumo em Inglês:

ABSTRACT The objective was to evaluate the productivity, microbiology and histopathology of the jejunum, ceca and liver in broilers fed a control or a high non-starch polysaccharide (HNSPs) diet added with an extract of humic substances (EHS). 240 broilers individually allocated, from 21-42 d of age were assigned to a factorial arrangement of 2 types of diets: 1) A corn/soybean meal diet (Control) and 2) As Control plus 7% distillers dried grain with solubles and 12% of wheat bran (HNSPs), and 3 growth promoters: 1) Antibiotic growth promoters (AGP); 2) without AGP (NAGP) and C) with 0.5% of EHS. At the end of the trial, the breast and carcass were weighed and samples of the intestine, ceca and liver were taken for microbial and histopathology analysis. Results were subjected to ANOVA. EHS-fed broilers had lower feed conversion ratio (FCR) and total aerobic bacterial (TAB) counts in the liver and higher ashes digestibility with the Control diet, but negative responses were seen with the HNSPs diet (Type of diet and growth promoter interaction, p≤0.05). The lesion scores in the jejunum were lower in EHS-fed broilers with the Control and HNSPs diet (p≤0.05). The TAB and E. coli were lower in the jejunum and ceca of AGP-fed broilers (p<0.01) compared to NAGP and EHS groups. EHS-fed broilers showed improved FCR and ileal ashes digestibility and lower TAB in the liver with the Control diet and had lower lesion score in the jejunum and similar weight gain compared to the AGP-fed broilers.

Resumo em Inglês:

ABSTRACT Bone mineralization is considered an essential source of minerals for metabolic needs that provide strength and hardness to the bone tissues and in birds its development can be enhanced by the use of dietary supplements. The present study was executed to evaluate the influence of prebiotic, probiotic and antibiotic on the morphometric aspects of tibia bone in broilers. One-hundred and sixty-one-day-old broiler chick were divided randomly into four groups (n=40) with 4 replicates (n=10 in each replicate). Group-I fed with only corn based basal diet and served as controlled group. Group-II with antibiotic supplement (Zinc bacitracin 0.04%), Group-III with probiotic supplement (lactobacillus 0.1%) & Group-IV with prebiotic supplement (mannan oligosaccharide 0.1%). On the 35th day, two birds were selected randomly from each replicate and slaughtered to record the morphometric parameters of both right and left tibia bones from each bird. The findings showed that the length, weight, thickness of lateral and medial wall, tibiotarsal index of bone and bone ash percentage of supplemented groups have had significant (p<0.05) difference when compared to that of the controlled group. The weight/length index in birds supplemented with prebiotic and probiotic was significantly higher (p<0.05) than in the antibiotic supplemented and control group. Medullary canal diameter of all the supplemented groups was significantly lower (p<0.05) than the control group. No significant (p>0.05) difference of robusticity index and diaphysis diameter was observed among various groups. A significant (p<0.05) low level of Alkaline Phosphatase while higher level of Calcium and Phosphorus was recorded in the supplemented groups compared to that of the control group. In conclusion, the use of prebiotic and probiotic as growth promoter can exhibit some underline mechanisms in the form of enhancement of bone quality, density and characteristics in broiler chicks as compared to common antibiotics.

Resumo em Inglês:

ABSTRACT The aim of this study is to determine the serum amino acid profile using Liquid Chromatography-Tandem Mass Spectrometry (LC-MS / MS) in healthy male and female geese of the same age that were raised in similar care and feeding conditions. The animal material of the study consisted of a total of 41 geese, 18 male, and 23 female of the same age (9 months). After a 12h fasting period of the geese, blood samples were taken from V. subcutanaeulnaris into tubes without anticoagulant. After separating the serums, the samples were preserved at -20 O C degrees until Methylglutaryl (Met-Glu), Valine (Val), Leucyl-Isoleucine (Leu-Ile), Methionine (Met), Phenylalanine (Phe), Argininosuccinate (ASA), Tyrosine (Tyr), Aspartic acid (Asp), Alanine (Ala), Arginine (Arg), Citrulline (Cit), Glycine (Gly), Ornithine (Orn), Glutamic acid (Glu) were analyzed. The Val, Asp, Arg, Cit, Gly, and Orn levels of male geese were higher compared to female geese in the research (p<0.05). It was determined that Asp, Arg, Cit, and Gly levels increased as the body weights of the geese increased (p<0.05). It was also determined that the effect of Gender x Body Weight interaction on Val, Cit, and Orn levels was significant (p<0.05). As a result; it has been concluded that the serum amino acid profile of healthy geese can vary according to gender and live weight, and more studies are needed to elucidate the reasons for these changes.

Resumo em Inglês:

ABSTRACT This study was conducted to investigate the effect of Ganoderma lucidum extract (GLE) on the gut morphology and cecal microbial community of broilers challenged with lipopolysaccharide (LPS). 144 one-day-old unsexed broiler chicks were randomly distributed into four treatments: non-challenged broilers fed a basal diet; LPS-challenged broilers fed a basal diet; LPS challenged broilers fed a basal diet supplemented with 1 mL/L of GLE in the drinking water; and LPS challenged broilers fed a basal diet supplemented with 1.33 mL/L of GLE in the drinking water. Results showed that supplementationwith1.33 mL/L of GLE alleviated intestinal inflammatory gene expression in LPS-challenged broilers (p≤0.05). Supplementation of GLE (1 and 1.33 mL/L) increased the villus height in the jejunum and ileum of LPS-challenged broilers (p≤0.001). Weighted principal coordinate analysis, heat map of species abundance, and microbial function pathway revealed distinct separation between the groups treated with LPS only and LPS in combination with GLE supplementation (1 and 1.33 mL/L). The abundance of the genus Faecalibacterium was increased in the cecal digesta of LPS-challenged broilers receiving GLE(1 and 1.33 mL/L) compared with the LPS challenge-only group (p≤0.001). The growth performance parameter of broilers was positively associated with the abundance of the genus Faecalibacterium in the cecal digesta. In conclusion, GLE supplementation could modulate gut morphology and cecal microbiota composition of broilers under inflammatory challenge.

Resumo em Inglês:

ABSTRACT This study was conducted to develop predictive equations for carcass characteristics and primal cut weights of native Mexican guajolotes using body measurements (BM). For this study, a total of 36 male guajolotes (Meleagris gallopavogallopavo), aged 6 to 10 months, and mean slaughter body weight (SBW) of 4543.14 ± 656.60 g, were used. The birds were kept under traditional extensive conditions. ThefollowingBMswererecorded24 h before slaughter: thoracicperimeter (TP), body circumference (BC), body length (BL), wing length (WL), keel length (KL), shank length (SL) and shank diameter (SD). After slaughter, hot carcass weight (HCW), cold carcass weight (CCW), hot dressing percentage (HDP), cold dressing percentage (CDP), organs and viscera weight (VIS) and abdominal fat weight (AFW) were recorded. The carcasses were dissected in to five primal cut (breast, thigh, drumstick, back and wing). The SBW and BMs showed moderate to high positive correlations (p<0.01; 0.34≤r<0.97) with carcass characteristics and primal cut weights. In the equations generated to predict HCW, CCW, HDP, CDP, VIS and AFW, the R2 ranged from 0.40 to 0.96, and the predictor variables were SBW, KL, BC, WL and SL. Regarding the equations developed to predict the primal cut weights, R2 ranged from 0.58 to 0.91. In these models, SBW, BC, SD, WL and KL explained most of the observed variation. The prediction equations obtained in the study had moderate to high accuracy; therefore, they can be used by researchers, technicians and poultry producers to obtain information on the carcass composition of native Mexican guajolotes.

Resumo em Inglês:

ABSTRACT It was investigated if pre-incubation ascorbic acid (AA) injection in fertile eggs incubated at high temperature impacts the performance, the yield of carcass and parts, and the intestine morphology of broilers reared under heat stress. Three thousand Cobb® fertile broiler eggs were randomly distributed according to weight into three incubations treatments (eggs not injected with AA and incubated at 37.5°C; eggs not injected with AA and incubated at 39°C; and eggs injected with 6 µg AA/100 µL water prior to incubation and incubated at 39ºC). The hatched birds were reared at thermoneutral, cold, and hot house temperatures. Broilers reared under hot temperature presented lower feed intake and weight gain than the broilers of the different rearing temperatures. Egg incubation at 39.0 ºC and 39.0 ºC + AA reduced broiler viability. Carcass and cut yields were not influenced by incubation and rearing procedures. Duodenal goblet cell count was lower in broilers from eggs of the treatment 39ºC + AA than in broilers from the other incubation treatments and in broiler rearing in hot temperature. In the jejunum, the goblet cell counts were higher in broilers that were reared under hot than thermoneutral temperatures. The incubation treatment of 39 ºC+AA increased the goblet cell counts in the ileum of broilers reared under cold temperatures. Rearing temperature influenced the duodenal villi counts, which were lower under cold rearing conditions than in the two other rearing temperatures. The results showed that egg incubation at 39°C, independently of ascorbic acid injection, did not produce an effective epigenetic heat adaptation in broilers.

Resumo em Inglês:

ABSTRACT The present study was conducted to investigate the efficacy of oral administration of L. reuteri on growth performance, intestine histomorphology, immunological and gut microbiome of broilers. A total of twenty healthy chickens were used in a five-week experimental trial. Birds were assigned into one of two groups with orally administrated L. reuteri probiotic and without probiotic- (Control -Phosphate-buffered saline). A significant (p<0.05) body weight gain was observed in the chickens in L. reuteri treatment group compare to those in the control group at the end of the trial. In addition, the serum IGF-1 cytokines level significantly enhanced in L. reuteri treatment group. However, there were no notable effects observed on the villus height, crypt depth, muscularis thickness, and submucosal thickness in chickens orally inject with and without L. reuteri. At the phylum level, the presence of Firmicutes (99.5%) was highly abundantin the L. reuteri treatment group. Moreover, the fecal microbial communities of Lactobacillus (99.9%) showed average relative abundance at genus level in L. reuteri treatment group. From this, we concluded that oral administration of L. reuteri would be beneficial to enhance the body weight gain, gut microbiome, and immune status of broiler.

Resumo em Inglês:

ABSTRACT Studies on how washing and storage influence duck egg quality are scarce compared with those on chicken egg quality. The present study investigated the quality of washed and unwashed duck eggs stored at 7 ºC and 25 ºC for 8 weeks. Quality parameters, including Haugh unit (HU), yolk index, thick albumen ratio, albumen pH, and air cell size, indicated that egg quality deteriorated during prolonged storage, and cuticle staining confirmed that washing reduced cuticle coverage. Washed eggs stored at 7 ºC maintained high quality (grade B; HU: 54) according to the United States Department of Agriculture (USDA, 2000) after storage for 8 weeks, whereas unwashed eggs stored at 25 ºC exhibited a low but acceptable quality (grade B, but HU: 36) after 7 weeks. Strong correlations were observed between the quality parameters evaluated. In conclusion, duck eggs should be washed and then stored at 7 ºC to enhance microbial safety and maintain quality to achieve a shelf life of at least 8 weeks.

Resumo em Inglês:

ABSTRACT This study was conducted to investigate effects of vitamin A (VA) and vitamin K3 (VK3) on immune function and intestinal antioxidant capacity of aged laying hens. In a 3 × 3 factorial arrangement, the diets of 1080 Roman Pink laying hens (87 weeks old) was formulated with deficient, adequate and excess VA and VK3, including 0, 7000 and 14000 IU/kg VA and 0, 2.0 and 4.0 mg/kg VK3 for 8 weeks. Interactive effects between VA and VK3 were observed that VA and VK3 decreased the splenetic mRNA expression of inducible nitric oxide synthase (iNOS) and tumour necrosis factor α (TNF-α), but increased the plasma immunoglobulin G (IgG) content and jejunal mRNA expression of nuclear factor-like 2 (Nrf2). Hens fed adequate or excess VA had higher spleen index, mRNA expression of interleukin-10 (IL-10) in spleen, sIgA content, catalase (CAT), glutathione peroxidase and total dismutase (T-SOD) activity, and mRNA expression of polymeric immunoglobulin receptor (pIgR) in jejunum and lower mRNA expression of IL-1β in jejunum and iNOS, TNF-α in spleen. Furthermore, adequate or excess VK3 significantly increased plasma IgG content, the CAT, T-SOD and total antioxidant capacity activities, up-regulated the mRNA expression of pIgR, Nrf2, SOD1 and CAT in jejunum and down-regulated the mRNA expression of iNOS and TNF-α in spleen. In conclusion, dietary addition of adequate VA (7000 IU/kg) and VK3 (2.0 mg/kg) improved the immune function and intestine antioxidant capacity of aged laying hens and excess levels did not exhibit superior effects.

Resumo em Inglês:

ABSTRACT Investigating the factors that affect broiler chicken prices in Turkey is vital for understanding market formation. The parameters and factors likely to influence the price of broiler chicken were analyzed for the period between 2010-2020 in Turkey. The study adopted the boosting regression model to predict the correlation between broiler chicken consumer price and variable factors like broiler feed, corn, soybean meal, wheat prices, the dollar exchange rate, producer price index (PPI), and agricultural PPI. The accuracy of the estimation of the regression model created according to the results of the analysis was calculated as 86%. The producer price index variable caused the highest relative impact (25.63%) on broiler chicken meat prices. The highest positive correlation was obtained between the producer price index and the agricultural PPI (r = 0.984). Thus, it was determined that chicken prices were affected by feed raw material prices and the general economic conditions in Turkey. In addition to improving the prevailing economic conditions, an effective price control mechanism is required to prevent excessive price fluctuations in the sector. Simultaneously, it is essential to create policies to reduce input costs.

Resumo em Inglês:

ABSTRACT The objective of this study was to evaluate the effectiveness of a litter conditioning compound (LCC) based on 98% phyllosilicates (kaolinite) and 2% cinnamon essential oil to be applied on the litter of broiler houses. Animal performance, prevalence of footpad lesions, and litter quality (water activity, pH, and moisture) were evaluated, in addition to the effect on the incidence of Salmonella spp., evaluated by testing shoe-drag swabs, fecal samples, and organs. Twenty-one broiler houses with similar structure and rearing conditions were distributed in a completely randomized design with three treatments and seven replications each, as follows: T0: control, without the use of LCC; T100: application of 100 grams of LCC per m² of litter per week; T200: application of 200 grams of LCC per m² of litter per week. There was no significant effect of treatments on performance variables; however litter pH was lower when 200g/m2 was used in comparison with the control treatment, a result not verified for moisture and water activity (p>0.05). Our findings demonstrated significant reduction in the percentage of footpad lesions in birds that received the LCC (T0: 63.37%; T100: 41.38% and T200: 27.24%). A reduction in the number of positive flocks for Salmonella spp. Was also observed (with overall positivity rates of 17.86%, 12.14%, and 5% for treatments T0, T100, and T200, respectively). It is concluded that the product reduces the incidence of Salmonella spp. and also significantly reduces the incidence of footpad lesions, two important factors for the poultry industry.

Resumo em Inglês:

ABSTRACT Yolk proteins undergo digestion either inside the egg yolk or in the surrounding yolk sac membrane (YSM) before being consumed by the developing avian embryo. However, the mechanisms underlying the digestion of yolk proteins during embryogenesis are largely unexplored in the pigeon Columba livia domestica. To better understand these mechanisms, the present study examined the classes of activated proteases in the egg yolk and the gene expression patterns of cathepsin B (CTSB) and cathepsin D (CTSD), which encode for lysosomal cysteine and aspartic proteases, respectively, in the YSM. We investigated the activated proteases by applying different types of protease inhibitors to yolk samples taken from incubation day 16. Then, we detected the mRNA levels of CTSB and CTSD in the YSM at incubation days 6, 8, 10, and 12-17. Both cysteine and aspartic proteases appeared to be activated in the egg yolk. Moreover, CTSB expression increased progressively and reached the maximum value on day 13; however, it decreased significantly on days 14 and 15 and further reduced toward hatching (day 17). In contrast, CTSD expression was weak and fluctuated insignificantly during development. Our results suggest that the degradation of yolk proteins at late developmental stages largely occurs in the egg yolk itself, probably by the activated cysteine and aspartic proteases. Furthermore, cathepsin B in the YSM seems to have a primary role in protein digestion, but this role decreases toward hatching.

Resumo em Inglês:

ABSTRACT This study aimed to investigate the effect of supplementing 300 mg/kg tea polyphenols (TP) on yolk cholesterol content and production performance of laying hens during the egg-laying period. A total of 600 Roman laying hens aged 24 weeks were randomly divided into two dietary treatment groups. The feeding experiment lasted for 48 weeks. Layers fed basal diet supplemented with 0 (control group) and 300mg/kg TP (TP group) diet, respectively. The yolk cholesterol content, laying performance, and egg quality were determined at 28, 38, 48, 58, and 68 weeks of age. The yolk cholesterol content in the TP group was significantly decreased at 28-68 weeks of age (p<0.01), compared to the control group. There was a significant increase in laying rate in the TP group at 38 weeks of age (p<0.05), compared to the control group, while no significant differences during the other laying periods were obtained (p>0.05). The FCR significantly decreased in the TP group at 38 weeks of age whereas AEW significantly increased in the TP group at 58 weeks of age (p<0.05). Similarly, the eggshell thickness and eggshell strength in the TP group significantly increased (p<0.05), compared with the control group at 38 weeks of age. The albumen height and Haugh unit significantly increased at 28 weeks of age (p<0.05). In conclusion, the results showed that the diet supplemented with 300 mg/kg TP had positive effects on production performance of layers during the egg-laying period, and could lessen yolk cholesterol content significantly at 28-68 weeks of age.

Resumo em Inglês:

ABSTRACT This study investigated the effect of calcium (Ca) and phytase interaction on growth performance and bone quality in 1-42-day-old broiler chickens. A total of 624 female one-day-old Ross 308 broilers were allotted to 13 treatments with four replicates and 12 birds per replicate. A 2 × 6 factorial experiment was designed to test the combinations of 0.50% and 1.00% Ca with 0, 500, 1,000, 2,500, 5,000, and 10,000 FTU/kg phytase in the basal diet (0.25% non-phytate phosphorus, NPP). The control diet contained adequate Ca and phosphorus (P). Dietary Ca, phytase, and their interaction affected growth performance and bone mineralization of broilers at 1-42 days of age (p<0.05). The broilers fed with 1.00% Ca had lower body weight gain (BWG) and feed intake (FI) compared with the birds fed with 0.50% Ca (p<0.05). The BWG, FI, leg bone weight, and ash weight of the broilers fed with 0.25% NPP were lower than those of birds fed with the control diet (p<0.05). The addition of 500-10,000 FTU/kg phytase improved growth rate and leg bone quality, especially at 1.00% Ca (p<0.05). No differences were observed in growth performance and bone quality of 42-day-old broilers fed with 1.00% Ca + 2,500-10,000 FTU/kg phytase and the control diet (p>0.05). These data indicated that high doses of phytase (2,500-10,000 FTU/kg) alleviate the negative effects of Ca and P imbalance (Ca-to-NPP ratio = 4.0) on growth performance and bone mineralization of broiler chickens.

Resumo em Inglês:

ABSTRACT This study was carried out to investigate the morphological and histological structures of the testis, epididymis and vas deferens of the Al-Ahsa native rooster (ANR). There were two types of ANR; the brown feather one with light yellow shank and the black feather one with grey or dark grey shank. Their body weight was 1840.88± 92.13 g and 1555.66± 82.83g, respectively. The morphology of the testes showed that the black rooster has larger testes than the brown rooster and there was asymmetry in size between the right and left testis in both. They were grey yellowish in color and oval-shaped, situated in the abdomen dorsal to the proventriculus, the liver and the gizzard, cranial to the lungs, caudal to the abdominal sac and ventral to the kidneys. The histology of the testes revealed the capsule, the different cells of the lining epithelium of the seminiferous tubules and the interstitial tissue. The morphology of the epididymis was revealed pseudostratified columnar epithelium, light brown in color with c to L-shaped, located cranial to the testis and extended caudally to continue with vas deferens. The latter has columnar epithelium, light grey in color, run caudally medial to the kidneys and opened in the cloaca.

Resumo em Inglês:

ABSTRACT This study evaluated the viability of using soy gum (residue from soy processing to obtain degummed oil) as an emulsifier in starter diets for broilers (1 to 21 days). For this, 600 1-day-old male broilers (Cobb® 500) were randomly assigned in a factorial arrangement (3 x 4), with three levels of gum inclusion (0, 1.25, and 2.5%) and four levels of soybean oil (0,1.3, 2.6, and 3.9%), with 5 replicates of 10 birds each. At 7, 14, and 21 days of age, we analyzed the performance parameters, pancreatic lipase activity and digestibility coefficients. Inclusion of soy gum improved (p<0.05) the performance and the digestibility coefficient of the ether extract, increased (p<0.05) the levels of AME and AMEn. The higher inclusion of gum (2.5%) as an emulsifier resulted in improved performance, showing the best values of feed conversion, with increased ether extract digestibility, increased AME content of the diets, and a lower requirement for pancreatic lipase in micelle formation.

Resumo em Inglês:

ABSTRACT This study investigates the effects of Hesperidin added to quail ration at different rates on some microbiological and physicochemical, lipid peroxidation, and lipid profiles in thigh meat. The current study had a duration of 35 days and used Pharaoh quails (Coturnix Pharaoh). The grouping was done in three treatment groups: Control, HES500, and HES1000 (each group was divided into five subgroups), and 0, 500, and 1000 mg/kg of Hesperidin was added to the basal diet of the groups, respectively. Adding Hesperidin and storage time affected the pH parameter in meat. It affected colour parameters depending upon the added Hesperidin (p<0.05). There was a significant difference in the number of total mesophilic aerobic bacteria (TMAB) in comparison with the control group according to the storage time (p<0.05). Palmitic, α-linolenic, oleic acid, eicosapentaenoic, and docosahexaenoic acids, which are among the individual fatty acids, differed between the control, HES500 and HES1000 groups (p<0.05). Hesperidin addition reduced lipid peroxidation on the 3rd, 5th, and 7th days of storage (p<0.05). Consequently, in direct proportion to the hypothesis at the beginning of the study, it was specified that adding Hesperidin reduced its concentration on lipid oxidation and had a positive effect on meat quality in terms of colour parameters.

Resumo em Inglês:

ABSTRACT Adapting existing laying facilities to meet animal welfare certifications is not a simple task. It causes higher expenses to producers, who are often hesitant to accept the need for changes. Considerations of their financial situation make them insecure to make assertive decisions in this area, as they seek to maintain the economic efficiency of laying poultry. This study aims to analyze the economic viability of laying systems (conventional cages and Cage-Free) with different housing densities. The data source was a systematized literature review. Five articles were found containing reports on systems. Further data sources were the lineage handbook and a survey with companies specializing in poultry farming. An analysis of economic viability was performed in the multiple scenarios. Densities in each system were used to compose different scenarios: Conventional: 1,500 cm²/bird, 750 cm²/bird, and 398 cm²/bird; and Cage-Free:7 birds/m² and 13 birds/m². The scenarios were evaluated in terms of Net Present Value, Internal Rate of Return, Modified Internal Rate of Return, Discounted Payback Method, Profitability Index, Equivalent Uniform Annual Value, and Monte Carlo Simulation. The best scenario was the Conventional, with 398 cm²/bird, presenting a higher NPV. The Cage-Free system, with seven birds per square meter, had a lower NPV compared to conventional systems. All scenarios had satisfactory chances of success. The risks of negative or null financial return were low according to Monte Carlo simulations. Conventional and Cage-Free production are economically viable when using densities of 1,500 cm²/bird, 750 cm²/bird, or 398 cm²/bird (conventional), and 7 birds/m², or 13 birds/m² (Cage-Free).

Resumo em Inglês:

ABSTRACT This experiment evaluated the effects of Saccharomyces cerevisiae (S. cerevisiae) and citric acid on production performance, egg quality, intestine histomorphology, and avian β-defensin 1 and 2 (AvBD 1 and 2) gene expressions in laying Japanese quails. A total of 400 48-day-old quails were randomly assigned to a 2×2×2 factorial arrangement of treatments with 5 replicates (each containing 10 quails) for 7 weeks. Variable factors consisted of S. cerevisiae (0 and 100 mg/kg diet), citric acid (0 and 5 g/kg diet), and Virginiamycin (0 and 50 mg/kg diet). At the completion of the trial, one bird per replicate was randomly killed, and jejunal tissue samples were removed to evaluate intestinal morphometric characteristics. Samples were taken from the midpoint of the jejunum to measure the gene expression of AvBD 1 and 2. Dietary inclusion of both S. cerevisiae and citric acid resulted in increased egg weight, egg mass, reduced feed intake, and improved FCR (p<0.05). The addition of S. cerevisiae to diets containing citric acid reduced feed intake, increased egg weight, and improved FCR (p<0.05). Shell weight and shell thickness were increased in birds fed each of S. cerevisiae and citric acid supplements (p<0.05). Dietary S. cerevisiae and citric acid similarly increased intestinal villus height, width, surface area, and the villus height to crypt depth ratio (p<0.0001). Results showed that AvBD 1 and 2 genes expression were up-regulated on quails fed S. cerevisiae-supplemented diets (p<0.0001). In conclusion, these results suggest that supplementation of S. cerevisiae and citric acid as functional feed additives either alone or in combination could be a potential alternative to antibiotics in the diet of Japanese laying quails.

Resumo em Inglês:

ABSTRACT Guinea fowl have several advantages over chickens. These birds are highly valued for their meat and eggs, particularly in tropical regions. They are currently in many parts of the world. Recently, the demand for guinea fowl meat has increased because it is considered a high-quality protein source. In addition, their eggs are delicious and considerably better than those of chickens. Guinea fowl eggs are valued for their thick shells, and longer shelf life, and it has premium prices compared with commercial and indigenous chickens. Chicken eggs have been well studied for egg and meat quality. However, such information isn’t so sufficiently documented in other poultry species. Despite the interest in guinea fowl production, it is vital to take cognizance of the fact that there is a lack of information on the production and quality of guinea fowl products, in contrast to commercial chickens. Therefore, the present review aims to assess the egg and meat quality of Guinea fowl in different tropical regions. The main results of the current study showed that the external egg quality characteristics, mainly (egg weight, shell percentage, and shell thickness), and internal egg quality traits, mainly (albumen weight, haugh unit, yolk height, and yolk color) of Guinea fowl differed under different tropical regions. Concerning carcass characteristics, a clear difference was observed in dressing percentage and breast percentage of Guinea fowl in various tropical areas. A similar trend was observed for the meat color.

Resumo em Inglês:

ABSTRACT This study aimed to evaluate the effects of different exogenous protease and carbohydrase in broiler diets on the nitrogen-corrected apparent metabolizable energy (AMEn) and standardized ileal amino acid digestibility (SIAAD) of soybean meals (SBM) in two Brazilian regions (Minas Gerais-MG and Rio Grande do Sul-RS). The total excreta collection of 528 14-d-old chicks was used to determine AMEn in a completely randomized design in a 2 (SBM MG and RS) x 5 (enzyme A, B, C, D and basal diet) + 1 (reference diet, RD) factorial arrangement, totaling 11 treatments, 8 repetitions, and 6 birds per experimental unit. Two experimental treatments (T1 and T6) without enzyme supplementation formulated with SBM MG and RS were used as negative control (NC). The RD without the inclusion of SBM MG and RS was used to correct the nitrogen balance. To determine the SIAAD, ileal content was collected from of broilers and the same experimental design and treatments of the previous trial were used except for the RD, which was replaced with a nitrogen-free diet (NFD) to quantify the excretion of endogenous amino acids. Soybean meal from MG showed the highest levels (p<0.05) of AME and AMEn (3,188 kcal/kg and 2,700 kcal/kg, respectively) in comparison to SBM RS (3,121 kcal/kg and 2,549 kcal/kg, respectively) and, when supplemented with the exogenous enzyme C, also improved the SIAAD (p<0.05), as compared to other enzymes.

Resumo em Inglês:

ABSTRACT The objective of this study was evaluate whether pretransport feed withdrawal affects welfare, carcass, and meat characteristics of European quails. A total of 120 European quails were used, with an initial age of 15 days. Bird feed was removed before transport to the slaughterhouse at the following times, which characterised the different treatments: zero hours, three hours, six hours, nine hours and twelve hours. The transport took 54 minutes to cover 27 kilometres to a commercial slaughterhouse. The birds were slaughtered at 41 days of age. During bleeding, blood samples were collected. Blood glucose, total protein, albumin, uric acid, and corticosterone concentrations were measured. The carcasses and meat characteristics were measured. Poultry body weight decreased and blood glucose concentrations increased with the increase in feed withdrawal time. The treatments did not affect carcass weights. Carcass yields after three hours fasting were similar to those in the six hours and nine hours groups, indicating that gastrointestinal tracts were empty after the third hour. Meat quality was negatively affected (pH, lightness, water holding capacity, cooking loss) by the increase in feed withdrawal time; integrated parameters that characterise dark, firm, dry meat. Pre transport feed withdrawal time should be three hours to empty the gastrointestinal tract and minimise losses in meat quality of European quails. It is necessary to adjust feed withdrawal so that it does not exceed this time, since there is no technical justification for supporting it.

Resumo em Inglês:

ABSTRACT The effect of including partially dehulled sunflower seeds in the diet of grazing chickens in meat quality was evaluated. Two hundred and forty, one-day-old, Ross 308 chickens were used, randomly distributed into four treatments with six replicates of 10 birds each. Seventy-two birds were slaughtered at seven weeks of age, 18 per treatment, extracting the Pectoralis major muscle to analyze meat quality. The treatments were completely randomized in a 2x2 factorial arrangement, where type of rearing (confinement or grazing) and diet (base diet or base diet substituting 10% soybean meal for partially dehulled sunflower seeds) were the independent variables. The grazing chickens spent 8 hours a day in a white clover (Trifolium repens) paddock. Including sunflower seeds improved (p<0.05) the color and crude protein (CP) in breast meat (p<0.05), while grazing increased (p<0.05) CP, dry mater (DM), and shear force (SF), and the percentage of breast fat decreased (p<0.05) by up to 50%. Additionally, grazing increased (p<0.05) saturated fatty acids (SFA) and reduced (p<0.05) lipid oxidation by up to 50%. Partially replacing soybean meal with partially dehulled sunflower seeds in the diet of grazing chickens with white clover improves the physicochemical characteristics and nutritional quality of the breast meat; it also decreases lipid oxidation, extending the shelf life of the meat.

Resumo em Inglês:

ABSTRACT Due to the genetic similarity of pathogenic Escherichia coli isolated from birds and pathotypes of human origin, it is suggested that they have a common ancestor and may exchange virulence-associated genes. This study aimed to detect virulence-associated genes in E. coli strains isolated from the Red-browed Amazon parrot (Amazona rhodocorytha) kept at a conservation institute in Brazil. High genetic variability in virulence was observed, since 12 virulence profiles were found among 14 strains. The number of virulence-associated genes of single strains ranged from 5 to 22 out of 33 genes tested, and only one strain did not present any virulence genes. Regarding adhesion genes, most strains presented from two to five genes, and crlA (85.7%) and fimC (85.7%) were the most frequent. Frequencies were similar for invasion and iron acquisition genes. Variations among genes were observed for serum resistance and toxin-related genes. Some of the E. coli strains isolated from parrots presented virulence genes that are commonly associated with pathotypes of human origin, including newborn meningitis E. coli, uropathogenic E. coli, and sepsis-associated E. coli. It is noteworthy that some of these genes were present in the majority of the analyzed strains. Our results indicate that these strains detected in clinically healthy parrots can be potential reservoirs of several virulence-associated genes. These genes can be transmitted to other E. coli strains, including those that affect humans. These E. coli strains present a high pathogenic potential of virulence-associated genes in extraintestinal pathogenic E. coli strains.

Resumo em Inglês:

ABSTRACT Lipid metabolism dysfunction is closely related to obesity, inflammation, diabetes, lipodystrophy, cardiovascular disease. Along with having a positive effect on energy homeostasis during fasting or prolonged exercise through mitochondrial fatty acid oxidation (FAO), more than two dozen enzymes and transport proteins are involved in the activation and transport of fatty acids into the mitochondrial, providing insights into their critical roles in metabolism. CPT1A has been reported to be expressed ubiquitously in the body and associated with dire consequences affecting fat deposition as the key rate-limiting enzyme of FAO. However, there is a dearth of data on the specific role of CPT1A on adipogenic differentiation and adipocyte lipolysis on chicken. This study assessed CPT1A’s function in adipocyte differentiation andadipocyte lipolysis, and the mechanisms were investigated. We found that CPT1A knockdown (KD) promotes the differentiation of chicken preadipocytes into mature adipocytes. CPT1A KD increased PPARγ protein expression level. Expression levels of lipid synthesis-related genes were increased, and lipolysis genes were reduced. Also, CPT1A KD can encourage the formation of lipid droplets. So our results confirmed that knockdown of CPT1A induced the lipid differentiation and inhibited the β-oxidation process to promote the formation of lipid droplets. These findings may deepen our understanding on CPT1A function, especially its regulatory role in adipocyte biology.

Resumo em Inglês:

ABSTRACT In recent years, egg production has had an intense growth in Brazil, and Brazilian egg consumption per capita has significantly increased in the last decade. To reduce sanitary and financial risks, decisions regarding the production and health status of the flock must be made based on objective criteria. Our aim was to determine the main “input” variables for the prediction of egg production performance in commercial laying breeder flocks using an ANN model. The software NeuroShellClassifier and NeuroShell Predictor were used to build the ANN. A total of 26 egg-production traits were selected as input variables and eight as output variables. A database of 44,120 Excel cells was generated. For the training and validation of the models, 74.9% and 25.1% of the data were used, respectively. The accuracy of the ANN models was calculated and compared using the analysis of coefficient of multiple determination (R2), mean squared error (MSE), and an assessment of uniform scatter in the residual plots. The models for the outputs “weekly egg production,” “weekly incubated egg,”, “accumulated commercial egg,” and “viability” showed an R2 greater than 0.8. Other models yielded R2 values lower than 0.8. The ANN predicts adequately eight egg-production traits in the breeders of commercial laying hens. The method is an option for data management analysis in the egg industry, providing estimates of the relative contribution of each input variable to the outputs.

Resumo em Inglês:

ABSTRACT Chicken abdominal fat (AF) is an economically important trait, and many studies have been conducted on genetic selection for AF. However, previous studies have focused on detecting functional chromosome mutations or regions using gene chips. The present study used the specific-locus amplified fragment sequencing (SLAF-seq) technology to perform a genome-wide association study (GWAS) on purebred Wengshang Barred chicken. A total of 1,286,715 single-nucleotide polymorphisms (SNPs) were detected, and 175,211 SNPs were selected as candidate SNPs for genome-wide association analysis using TASSEL general linear models. Two SNPs markers reached genome-wide significance. Of these, rs7943847, rs127627362 were significantly associated with AF at 120 days. These SNPs are close to eight genes (SLC16A6, ARSG, WIPI1, PRKAR1A, FAM20A, ABCA8, ABCA9, CPQ,). These results would enrich the studies on AF and promote the use of Chinese chicken, especially the Wenshang Barred chicken.

Resumo em Inglês:

ABSTRACT This work was developed to evaluate the impact of the addition of proteases on the performance characteristics, egg quality, relative weight of digestive organs, and intestinal morphometry of laying hens. 390 Hy Line W36® hens were allocated into five treatments and six replicates with 13 animals. The treatments were: 1) Control (standard formulation), 2) Negative control A - NCA (nutritional reduction according to protease A matrix), 3) Negative control B - NCB (nutritional reduction according to protease B matrix), 4) NCA+protease A (0.250 g/kg of feed) and 5) NCB+protease B (0.125 g/kg of feed). Hens fed the NCA, NCB, and NCA+protease A diets showed reductions in feed intake and egg mass. The addition of protease B provided better results for egg production in both percentage and per dozen as compared to the group fed with the NCA+protease A diets. The hens subjected to diets NCA and NCB showed eggs with a reduced eggshell and thickness percentage. However, supplementation with proteases A and B improved these parameters to values similar to the controls. There was no significant effect of the treatments on the relative weight of the liver, proventricle, gizzard, pancreas, and small intestine. However, the addition of protease A resulted in a decreased value for the relative weight of the large intestine. The jejunum and ileum crypt depths were, respectively, smaller in hens fed the control diet in relation to the NCB diet and the NCA and NCB diets. As it can be concluded, Protease B supplementation provided the best performance results.