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Iranian Journal of Applied Animal Science, 2018
Betaine is donor of methyl groups and can partially replace methionine in diets for this purpose.... more Betaine is donor of methyl groups and can partially replace methionine in diets for this purpose. The objective of this study was to evaluate three sources of betaine in partial substitution of methionine supplement in broiler diets. The Cobb-500 broiler chickens were allocated in a completely randomized experimental design with 5 treatments and 7 replicates of 49 birds each. The positive control treatment consisted of standard level of digestible methionine, the negative control was the digestible methionine reduced by 17% and the other three treatments consisted of the negative control diet supplemented with natural betaine (95%) or hydrochloride betaine (72%), HCl 1 and HCl 2 that had the same composition, and were obtained from two different manufacturers. The performance was evaluated from 7 to 21 days, 7 to 35 days and 7 to 43 days. At 43 days, the carcass and carcass parts (breast, thigh+drumstick, liver and abdominal fat) were determined and an economic analysis of each diet...
Frontiers in Sustainable Food Systems, 2018
The objective of this study was to evaluate the effects of dietary autolyzed yeast (AY; Saccharom... more The objective of this study was to evaluate the effects of dietary autolyzed yeast (AY; Saccharomyces cerevisiae) supplementation on growth performance, immune system, and intestinal bacterial count in broiler chickens. A total of 1,260 1-day-old male Ross AP95 chicks were placed in a completely randomized design (4 treatments, 7 replicates each, and 45 birds/replicate). The treatments were: basal diet-negative control (NC); basal diet supplemented with 55 ppm of zinc bacitracin-positive control (PC); NC + 0.2% of AY; NC + 0.4% of AY. The diets were formulated based on corn-soybean meal with 5% inclusion of wheat bran and 5% of poultry by-product meal. At 7 days of age, all birds were eye drop-vaccinated with live vaccine against coccidiosis. At 8 and 21 days of age, one chicken per pen was then euthanized by cervical dislocation to collect ileal and cecal contents for enumeration of Enterococcus sp., Escherichia coli and Lactobacillus sp. Yet, ileal samples were collected to analyze the gene expression of Claudin-1, IL-1β, IL-4, TLR-4, and MUC-2 through real time PCR. On d 21, it was observed that the inclusion of 0.2% of AY improved FCR (P < 0.05) when compared to the NC treatment. In the overall experimental period, the inclusion of zinc bacitracin and 0.4% of AY improved FCR (P < 0.05) compared to the NC group. On d 8, supplementation of 0.2% of AY increased Enterococcus and both concentrations of AY reduced Lactobacillus in the ileal digesta compared to birds supplemented with zinc bacitracin. On d 21, 0.2% of AY reduced E. coli in the cecal digesta. On d 8, AY supplementation downregulated the expression of TLR-4 vs. the PC group (P = 0.04). On d 21, supplementation of AY upregulated the expression of IL-1β (P < 0.05) vs. the NC group. Supplementation of AY improved the growth performance of broiler chickens vaccinated against coccidiosis, partially explained by the modulation of the intestinal microbiota and immune-system.
Journal of Animal Physiology and Animal Nutrition, 2018
The purpose of this study was to verify the ability of a probiotic in the feed to maintain the st... more The purpose of this study was to verify the ability of a probiotic in the feed to maintain the stability of the gut microbiota in chickens after antibiotic therapy and its association with growth performance. One thousand six hundred twenty 1-day-old Cobb male were housed in floor pens (36 pens, 45 birds/pen) and were fed corn-/ soya bean meal-based diets supplemented with or without probiotic (Bacillus subtilis) during the entire rearing phase. From 21 to 24 days of age (three consecutive days), the chickens were submitted to antibiotic therapy via drinking water (bacitracin and neomycin) in order to mimic a field treatment and induce dysbiosis. Growth performance was monitored until 42 days of age. At 2, 4 and 6 days after antibiotic therapy, three chickens from each pen were euthanized and the contents of the small intestine and caeca were collected and pooled. The trial was conducted with four treatments and nine replicates in a 2 × 2 factorial arrangement for performance characteristics (with and without probiotic × with and without antibiotic therapy); for the intestinal microbiota, it was in a 2 × 2 × 3 factorial arrangement (with and without probiotic × with and without antibiotic therapy × 2, 4 and 6 days after the antibiotic therapy) with three replicates per treatment. Terminal restriction length polymorphism (T-RFLP) analysis showed that the structure of gut bacterial community was shaped by the intestinal segment and by the time after the antibiotic therapy. The number of 16S rDNAs copies in caecum contents decreased with time after the therapeutic treatment. The antibiotic therapy and dietary probiotic supplementation decreased richness and diversity indexes in the caecal contents. The improved performance observed in birds supplemented with probiotic may be related to changes promoted by the feed additive in the structure of the intestinal bacterial communities and phylogenetic groups. Antibiotic therapy modified the bacterial structure, but did not cause loss of broiler performance.
Revista Brasileira de Ciência Avícola, 2017
Revista Brasileira de Ciência Avícola, 2014
This study evaluated the metabolic response of broilers fed diets containing increasing crude gly... more This study evaluated the metabolic response of broilers fed diets containing increasing crude glycerine levels in two bioassays. Birds were house in metabolic cages, and were distributed according to a completely randomized experimental design with five treatments of 4 replicates each (1 st assay: 5 birds/ cage; 2 nd assay: 1-20 days = 8 birds/ cage, and 21-42 days = 4 birds/cage). Treatments consisted of a control diet based on corn and soybean meal, and four other diets containing 2.5%, 5.0%, 7.5% and 10.0% glycerine derived from biodiesel. In experiment I, there was no effect (p>0.05) of glycerol level on liver weight or blood parameters. Serum blood glycerol levels of the birds fed 10% crude glycerine increased during the first nine days of diet intake (p<0.05). In experiment II, water intake increased (p<0.05) in the birds fed 7.5 and 10.0% crude glycerine at 4 and 8 days of age. Feed intake increased (p<0.05) on days 8 and 12 in birds fed 2.5 and 7.5% glycerine. Fecal moisture increased (p<0.05) in birds fed diets with 5.0, 7.5, and 10.0% crude glycerine on days 16 and 20. Ileal content moisture was not different (p>0.05) among treatments when birds were 42 days old. High dietary glycerine levels may induce metabolic change in broilers, such as increased blood glycerol level, water intake and fecal moisture.
Applied and Environmental Microbiology, 2015
Salmonella enterica serovars Typhimurium ( S . Typhimurium) and Enteritidis ( S . Enteritidis) ar... more Salmonella enterica serovars Typhimurium ( S . Typhimurium) and Enteritidis ( S . Enteritidis) are foodborne pathogens, and outbreaks are often associated with poultry products. Chickens are typically asymptomatic when colonized by these serovars; however, the factors contributing to this observation are uncharacterized. Whereas symptomatic mammals have a body temperature between 37°C and 39°C, chickens have a body temperature of 41°C to 42°C. Here, in vivo experiments using chicks demonstrated that numbers of viable S . Typhimurium or S . Enteritidis bacteria within the liver and spleen organ sites were ≥4 orders of magnitude lower than those within the ceca. When similar doses of S . Typhimurium or S . Enteritidis were given to C3H/HeN mice, the ratio of the intestinal concentration to the liver/spleen concentration was 1:1. In the avian host, this suggested poor survival within these tissues or a reduced capacity to traverse the host epithelial layer and reach liver/spleen sites ...
Iranian Journal of Applied Animal Science, 2018
Betaine is donor of methyl groups and can partially replace methionine in diets for this purpose.... more Betaine is donor of methyl groups and can partially replace methionine in diets for this purpose. The objective of this study was to evaluate three sources of betaine in partial substitution of methionine supplement in broiler diets. The Cobb-500 broiler chickens were allocated in a completely randomized experimental design with 5 treatments and 7 replicates of 49 birds each. The positive control treatment consisted of standard level of digestible methionine, the negative control was the digestible methionine reduced by 17% and the other three treatments consisted of the negative control diet supplemented with natural betaine (95%) or hydrochloride betaine (72%), HCl 1 and HCl 2 that had the same composition, and were obtained from two different manufacturers. The performance was evaluated from 7 to 21 days, 7 to 35 days and 7 to 43 days. At 43 days, the carcass and carcass parts (breast, thigh+drumstick, liver and abdominal fat) were determined and an economic analysis of each diet...
Frontiers in Sustainable Food Systems, 2018
The objective of this study was to evaluate the effects of dietary autolyzed yeast (AY; Saccharom... more The objective of this study was to evaluate the effects of dietary autolyzed yeast (AY; Saccharomyces cerevisiae) supplementation on growth performance, immune system, and intestinal bacterial count in broiler chickens. A total of 1,260 1-day-old male Ross AP95 chicks were placed in a completely randomized design (4 treatments, 7 replicates each, and 45 birds/replicate). The treatments were: basal diet-negative control (NC); basal diet supplemented with 55 ppm of zinc bacitracin-positive control (PC); NC + 0.2% of AY; NC + 0.4% of AY. The diets were formulated based on corn-soybean meal with 5% inclusion of wheat bran and 5% of poultry by-product meal. At 7 days of age, all birds were eye drop-vaccinated with live vaccine against coccidiosis. At 8 and 21 days of age, one chicken per pen was then euthanized by cervical dislocation to collect ileal and cecal contents for enumeration of Enterococcus sp., Escherichia coli and Lactobacillus sp. Yet, ileal samples were collected to analyze the gene expression of Claudin-1, IL-1β, IL-4, TLR-4, and MUC-2 through real time PCR. On d 21, it was observed that the inclusion of 0.2% of AY improved FCR (P < 0.05) when compared to the NC treatment. In the overall experimental period, the inclusion of zinc bacitracin and 0.4% of AY improved FCR (P < 0.05) compared to the NC group. On d 8, supplementation of 0.2% of AY increased Enterococcus and both concentrations of AY reduced Lactobacillus in the ileal digesta compared to birds supplemented with zinc bacitracin. On d 21, 0.2% of AY reduced E. coli in the cecal digesta. On d 8, AY supplementation downregulated the expression of TLR-4 vs. the PC group (P = 0.04). On d 21, supplementation of AY upregulated the expression of IL-1β (P < 0.05) vs. the NC group. Supplementation of AY improved the growth performance of broiler chickens vaccinated against coccidiosis, partially explained by the modulation of the intestinal microbiota and immune-system.
Journal of Animal Physiology and Animal Nutrition, 2018
The purpose of this study was to verify the ability of a probiotic in the feed to maintain the st... more The purpose of this study was to verify the ability of a probiotic in the feed to maintain the stability of the gut microbiota in chickens after antibiotic therapy and its association with growth performance. One thousand six hundred twenty 1-day-old Cobb male were housed in floor pens (36 pens, 45 birds/pen) and were fed corn-/ soya bean meal-based diets supplemented with or without probiotic (Bacillus subtilis) during the entire rearing phase. From 21 to 24 days of age (three consecutive days), the chickens were submitted to antibiotic therapy via drinking water (bacitracin and neomycin) in order to mimic a field treatment and induce dysbiosis. Growth performance was monitored until 42 days of age. At 2, 4 and 6 days after antibiotic therapy, three chickens from each pen were euthanized and the contents of the small intestine and caeca were collected and pooled. The trial was conducted with four treatments and nine replicates in a 2 × 2 factorial arrangement for performance characteristics (with and without probiotic × with and without antibiotic therapy); for the intestinal microbiota, it was in a 2 × 2 × 3 factorial arrangement (with and without probiotic × with and without antibiotic therapy × 2, 4 and 6 days after the antibiotic therapy) with three replicates per treatment. Terminal restriction length polymorphism (T-RFLP) analysis showed that the structure of gut bacterial community was shaped by the intestinal segment and by the time after the antibiotic therapy. The number of 16S rDNAs copies in caecum contents decreased with time after the therapeutic treatment. The antibiotic therapy and dietary probiotic supplementation decreased richness and diversity indexes in the caecal contents. The improved performance observed in birds supplemented with probiotic may be related to changes promoted by the feed additive in the structure of the intestinal bacterial communities and phylogenetic groups. Antibiotic therapy modified the bacterial structure, but did not cause loss of broiler performance.
Revista Brasileira de Ciência Avícola, 2017
Revista Brasileira de Ciência Avícola, 2014
This study evaluated the metabolic response of broilers fed diets containing increasing crude gly... more This study evaluated the metabolic response of broilers fed diets containing increasing crude glycerine levels in two bioassays. Birds were house in metabolic cages, and were distributed according to a completely randomized experimental design with five treatments of 4 replicates each (1 st assay: 5 birds/ cage; 2 nd assay: 1-20 days = 8 birds/ cage, and 21-42 days = 4 birds/cage). Treatments consisted of a control diet based on corn and soybean meal, and four other diets containing 2.5%, 5.0%, 7.5% and 10.0% glycerine derived from biodiesel. In experiment I, there was no effect (p>0.05) of glycerol level on liver weight or blood parameters. Serum blood glycerol levels of the birds fed 10% crude glycerine increased during the first nine days of diet intake (p<0.05). In experiment II, water intake increased (p<0.05) in the birds fed 7.5 and 10.0% crude glycerine at 4 and 8 days of age. Feed intake increased (p<0.05) on days 8 and 12 in birds fed 2.5 and 7.5% glycerine. Fecal moisture increased (p<0.05) in birds fed diets with 5.0, 7.5, and 10.0% crude glycerine on days 16 and 20. Ileal content moisture was not different (p>0.05) among treatments when birds were 42 days old. High dietary glycerine levels may induce metabolic change in broilers, such as increased blood glycerol level, water intake and fecal moisture.
Applied and Environmental Microbiology, 2015
Salmonella enterica serovars Typhimurium ( S . Typhimurium) and Enteritidis ( S . Enteritidis) ar... more Salmonella enterica serovars Typhimurium ( S . Typhimurium) and Enteritidis ( S . Enteritidis) are foodborne pathogens, and outbreaks are often associated with poultry products. Chickens are typically asymptomatic when colonized by these serovars; however, the factors contributing to this observation are uncharacterized. Whereas symptomatic mammals have a body temperature between 37°C and 39°C, chickens have a body temperature of 41°C to 42°C. Here, in vivo experiments using chicks demonstrated that numbers of viable S . Typhimurium or S . Enteritidis bacteria within the liver and spleen organ sites were ≥4 orders of magnitude lower than those within the ceca. When similar doses of S . Typhimurium or S . Enteritidis were given to C3H/HeN mice, the ratio of the intestinal concentration to the liver/spleen concentration was 1:1. In the avian host, this suggested poor survival within these tissues or a reduced capacity to traverse the host epithelial layer and reach liver/spleen sites ...