Use of Organic Acids and A Competitive Exclusion Product as Growth Promoter and Salmonella Enteritidis Control in Commercial Turkeys

It is estimated that Salmonella causes one million illnesses in the United States annually, with 19,000 hospitalizations and 380 deaths. There are various serotypes of this bacterium, and the serotypes Typhimurium and Enteritidis are commonly isolated from outbreaks and, in most cases, present resistance to the antibiotics utilized in clinical medicine. One of the current theories to explain the emergence of bacterial resistance is the continuous use of antibiotics as growth promoters in animal feeds. Despite the lack of evidences that antibiotic growth promoters cause bacterial resistance, the poultry industry has explored strategies to reduce or to eliminate the use of antibiotic growth promoters in the production chain, including the improvement of biosecurity programs, use of vaccines, genetic selection, and the feeding of other additives, such as organic acid blends (OAB) and competitive exclusion (CE) products. This study aimed at evaluating the effect of the continuous dietary supplementation of an OAB and a CE product on the growth performance, pH of the crop and cecal contents, control of Salmonella Enteritidis (SE) in the cecal content, and acute-phase protein serum levels in starter commercial turkeys. The additives promoting similar results as antibiotics under controlled experimental conditions should be further evaluated on commercial farms to allow their utilization under practical conditions. Supplementing commercial turkey diets with the evaluated OAB and CE product may reduce SE load. Serum OVT and AGP levels can be used as effective and fast indicators of infection, including that by SE.(AU)

Use of Organic Acids and A Competitive Exclusion Product as Growth Promoter and Salmonella Enteritidis Control in Commercial Turkeys

It is estimated that Salmonella causes one million illnesses in the United States annually, with 19,000 hospitalizations and 380 deaths. There are various serotypes of this bacterium, and the serotypes Typhimurium and Enteritidis are commonly isolated from outbreaks and, in most cases, present resistance to the antibiotics utilized in clinical medicine. One of the current theories to explain the emergence of bacterial resistance is the continuous use of antibiotics as growth promoters in animal feeds. Despite the lack of evidences that antibiotic growth promoters cause bacterial resistance, the poultry industry has explored strategies to reduce or to eliminate the use of antibiotic growth promoters in the production chain, including the improvement of biosecurity programs, use of vaccines, genetic selection, and the feeding of other additives, such as organic acid blends (OAB) and competitive exclusion (CE) products. This study aimed at evaluating the effect of the continuous dietary supplementation of an OAB and a CE product on the growth performance, pH of the crop and cecal contents, control of Salmonella Enteritidis (SE) in the cecal content, and acute-phase protein serum levels in starter commercial turkeys. The additives promoting similar results as antibiotics under controlled experimental conditions should be further evaluated on commercial farms to allow their utilization under practical conditions. Supplementing commercial turkey diets with the evaluated OAB and CE product may reduce SE load. Serum OVT and AGP levels can be used as effective and fast indicators of infection, including that by SE.

Traceability of animal by product meals in broilers fed sugarcane yeast using stable isotopes

The objective of this study was to verify if the dietary inclusion of sugarcane yeast at levels commonly used in broiler diets influences the traceability of cattle meat meal and poultry offal meal, using the technique of stable carbon and nitrogen isotopes in the breast muscle of chickens. A number of 325 one-d-old male broilers were randomly distributed into 13 treatments with 25 birds each. Treatments consisted of a control diet based on corn and soybean meal, and the inclusion of 1, 2, 4, or 6% meat and bone meal, poultry offal meal or sugarcane yeast. At 42 days of age, six birds per treatment were randomly selected, sacrificed, and their breast muscle was collected for isotopic ration analysis. The isotopic ratio of birds fed the diet with inclusion of 6% sugarcane yeast was different from those fed the control treatment, but not from those fed diets with the inclusion of 2, 4 and 6% meat and bone meal or 4 and 6% poultry offal meal. The inclusion of 6% sugarcane yeast in broiler diets based on corn and soybean meal may affect the traceability of animal by product meals.

Performance and egg quality of laying hens fed diets containing aflatoxin, fumonisin and adsorbent

The effects of aflatoxin and fumonisin and their combination on egg production and quality, as well as the efficacy of a mycotoxin adsorbent in reducing or eliminating these effects in commercial layers. A number of 168 layers with initial age of 37 weeks were submitted to an experimental period of 56 days. A completely randomized experimental design in a 3x2+1 factorial arrangement was applied (3 treatments with mycotoxins: aflatoxin (AF), fumonisin (FU), or aflatoxin + fumonisin (AF+FU); 2 treatments with or without adsorbent; and a control group that was fed no mycotoxins, nor adsorbent), totaling 7 treatments with 6 replicated of 4 birds/cage. The dietary inclusion levels were 1ppm AF, 25ppm FU, and 2 kg adsorbent/ton feed. Birds fed AF presented the lowest percentage of lay (p=0.0594). Egg mass was the lowest (p 0.05) in the AF+FU treatment (49.49g). The treatment with AF resulted in higher eggshell thickness and strength (p 0.05) than the FU treatment and the control group. The inclusion of the adsorbent in the AF contaminated feed reduced eggshell strength, which returned to levels similar to those of the control group. The observed changes indicate that aflatoxin is toxic at a concentration of 1ppm, and that the effects of fumonisin were less evident as a function of the low dose applied. The inclusion of the glucan (2kg/ton) effectively reverted some of the toxic effects of aflatoxin and, at lower extension, those of fumonisin, when these mycotoxins were invidually added to commercial layer feeds.

Efeito da temperatura ambiente e da idade do frango sobre o valor energético do farelo de soja

Two hundred and eighty-eight Cobb chicks were distributed in a completely randomized design with a split-plot arrangement with six replication of six chicks each, the main plots were in three temperatures (cold, thermo neutral and hot) and the secondary plot were by phase (initial, growing and final). The test diet was produced by replacing the basal diet with test food: 40% soybean meal+60% basal diet. The coefficient of apparent and true metabolizability of dry matter, nitrogen, ether extract of the test diet and apparent and true metabolizable energies (AME and TME) of soybean meal were calculated and energy values were corrected for nitrogen balance (AMEn and TMEn) of soybean meal, in kcal/kg, as fed basis. The mean values of AMEn observed for broiler chicks in cold, thermo neutral and hot temperature were 2110, 2016 and 2022kcal/kg, respectively, and the initial, growing and final phases were 1840, 2052 and 2256kcal/kg, respectively. The metabolizable energy values of soybean meal, the balance and coefficients of metabolizability of the nutrients of the test diet increased with the age of broiler; however, they were not affected by environmental temperature.

Foram utilizados 288 pintos de corte Cobb, distribuídos em delineamento experimental inteiramente ao acaso, em esquema de parcelas subdivididas no tempo, sendo as três temperaturas de criação - fria, termoneutra e quente - as parcelas, e as três fases de avaliação - inicial, crescimento e final - as subparcelas, com seis repetições de seis aves cada. A dieta-teste foi obtida pela substituição de parte da ração basal pelo alimento-teste: 40% do farelo de soja + 60% da ração basal. Foram calculados os coeficientes de metabolizabilidade aparente e verdadeiro da matéria seca, do nitrogênio, do extrato etéreo da dieta-teste e os valores de energia metabolizável aparente e verdadeira (EMA e EMV), e corrigidas pelo balanço de nitrogênio do farelo de soja (EMAn e EMVn). Foram encontrados valores médios de EMAn do farelo de soja para aves criadas em temperatura fria, termoneutra e quente de 2110, 2016 e 2022kcal/kg, respectivamente, e para as fases de criação inicial, crescimento e final de 1840, 2052 e 2256kcal/kg, respectivamente. O valor de energia metabolizável do farelo de soja, os balanços e os coeficientes de metabolizabilidade dos nutrientes da dieta-teste aumentaram com a idade do frango de corte, porém não são afetados pela temperatura ambiente.

Corn texture and particle size in broiler diets

The objective of this study was to evaluate the effect of corn texture and the particle size on broiler performance, carcass yield, nutrient digestibility, and digestive organ morphometrics. In Experiment I, 720 male Cobb chicks were distributed in a completely randomized experimental design with a 2 x 3 factorial arrangement, consisting two corn textures (dented and hard) and three corn particle sizes, was applied, with four replicates of 30 birds each. Corn particle size was classified according to geometric mean diameter (GMD) as fine - 0.46 mm; medium - 0.73 mm, and coarse - 0.87 mm. In Experiment II, 120 broiler chicks were used to evaluate corn digestibility during the periods of 16 to 22 days and 35 to 41 days of age, using the method of total excreta collection. In Experiment I, corn particle size influenced body weight, average weight gain, feed intake and feed conversion ratio of 21-day-old birds. Corn texture and particle size did not affect the performance of 42-day-old broilers or carcass traits. In Experiment II, there was no influence of corn texture and particle size on digestive organ weights. Dented corn increased nitrogen excretion in the first trial, and hard corn improved dry matter digestibility in the second metabolic trial. Corn with fine particle size promotes better performance of broilers at 21 days of age. Hard corn results in higher dry matter digestibility and lower nitrogen excretion, and consequently higher production factor in 42-day-old broilers.

Corn texture and particle size in broiler diets

The objective of this study was to evaluate the effect of corn texture and the particle size on broiler performance, carcass yield, nutrient digestibility, and digestive organ morphometrics. In Experiment I, 720 male Cobb chicks were distributed in a completely randomized experimental design with a 2 x 3 factorial arrangement, consisting two corn textures (dented and hard) and three corn particle sizes, was applied, with four replicates of 30 birds each. Corn particle size was classified according to geometric mean diameter (GMD) as fine - 0.46 mm; medium - 0.73 mm, and coarse - 0.87 mm. In Experiment II, 120 broiler chicks were used to evaluate corn digestibility during the periods of 16 to 22 days and 35 to 41 days of age, using the method of total excreta collection. In Experiment I, corn particle size influenced body weight, average weight gain, feed intake and feed conversion ratio of 21-day-old birds. Corn texture and particle size did not affect the performance of 42-day-old broilers or carcass traits. In Experiment II, there was no influence of corn texture and particle size on digestive organ weights. Dented corn increased nitrogen excretion in the first trial, and hard corn improved dry matter digestibility in the second metabolic trial. Corn with fine particle size promotes better performance of broilers at 21 days of age. Hard corn results in higher dry matter digestibility and lower nitrogen excretion, and consequently higher production factor in 42-day-old broilers.

Soybean Oil and Beef Tallow in Starter Broiler Diets

The objective of this study was to determine the energy values of soybean oil (SBO) and tallow (T) combined in different ratios, and to evaluate their effects on the performance, body composition, and serum lipid levels of starter broilers. In experiment I, a digestibility trial was performed to determine the energy value of the SOB and T mixtures using 100 12 - to 21 -day-old broilers. In experiment II, 930 one-day-old broilers were used. Treatments consisted of the inclusion of 4% SBO and T inclusions at the following ratios: 0:100, 25:75, 50:50, 75:25, 100:0. Each treatment included six replicates. In experiment I, AME and AMEn linearly increased (P 0.01), as SBO participation in the mixture increased. In experiment II, the different lipid ratios quadratically influenced (P 0.01) body weight and weight gain at 21 days of age, increasing up to the ratio of 65.87:34.13. Serum lipids linearly decreased (P 0.05) as SOB inclusion in the diet increased. It was concluded that AME and AMEn of SBO and T at ratios of 0:100, 25:75, 50:50, 75:25, and 100:0 were 7.882 and 7.542, 8.384 and 8.076, 8.701 and 8.385, 8.801 and 8.727, and 9.478 and 9.271 kcal/kg, respectively. The best performance with no detrimental effect on carcass yield was obtained with the mixture of 75% SBO with 25% T. The highest dietary soybean oil level reduced serum lipid levels of 21-day-old broilers.

Soybean Oil and Beef Tallow in Starter Broiler Diets

The objective of this study was to determine the energy values of soybean oil (SBO) and tallow (T) combined in different ratios, and to evaluate their effects on the performance, body composition, and serum lipid levels of starter broilers. In experiment I, a digestibility trial was performed to determine the energy value of the SOB and T mixtures using 100 12 - to 21 -day-old broilers. In experiment II, 930 one-day-old broilers were used. Treatments consisted of the inclusion of 4% SBO and T inclusions at the following ratios: 0:100, 25:75, 50:50, 75:25, 100:0. Each treatment included six replicates. In experiment I, AME and AMEn linearly increased (P 0.01), as SBO participation in the mixture increased. In experiment II, the different lipid ratios quadratically influenced (P 0.01) body weight and weight gain at 21 days of age, increasing up to the ratio of 65.87:34.13. Serum lipids linearly decreased (P 0.05) as SOB inclusion in the diet increased. It was concluded that AME and AMEn of SBO and T at ratios of 0:100, 25:75, 50:50, 75:25, and 100:0 were 7.882 and 7.542, 8.384 and 8.076, 8.701 and 8.385, 8.801 and 8.727, and 9.478 and 9.271 kcal/kg, respectively. The best performance with no detrimental effect on carcass yield was obtained with the mixture of 75% SBO with 25% T. The highest dietary soybean oil level reduced serum lipid levels of 21-day-old broilers.

Histomorphology of bursa of Fabricius: effects of stock densities on commercial broilers

During the past few years, there has been considerable interest on the effects of stocking density on broiler behavior and immunity. Stress may cause immunodeficiency by affecting cell and humoral responses, as well as body weight decrease, and foot-pad dermatitis. The aim of this study was to study histomorphological changes of the bursa of Fabricius in broilers submitted to three different stocking densities (10, 15, and 20 birds/m²) from one to 42 days of age. Three birds from each group were sacrifieced on days 7 and 42. The bursa was collected, fixed, and processed for histomorphometric assessment using a Kontrom KS 400 image analyzer. Data were analyzed by Biostat 3.0 (Tukey Test). The results of average cortical area percentage in bursal follicles of 6-week-old birds were 45.12a (10 birds/m²), 30.43b (15 birds/m²), and 23.77b (20 birds/m²). Average body weight was 2.58a kg (10 birds/m²), 2.56a Kg (15 birds/m²), and 2.47b Kg (20 birds/m²), respectively. The percentage of foot-pad dermatitis in 6-week-old birds was 3.33a (10 birds/m²), 17.76b (15 birds/m²), and 49.17c (20 birds/m²). These differences were statistically significant at a P 0.05 level. Under these experimental conditions,, it was concluded that the best stocking density to produce broilers is between 10-15 birds per square meter.

Histomorphology of bursa of Fabricius: effects of stock densities on commercial broilers

During the past few years, there has been considerable interest on the effects of stocking density on broiler behavior and immunity. Stress may cause immunodeficiency by affecting cell and humoral responses, as well as body weight decrease, and foot-pad dermatitis. The aim of this study was to study histomorphological changes of the bursa of Fabricius in broilers submitted to three different stocking densities (10, 15, and 20 birds/m²) from one to 42 days of age. Three birds from each group were sacrifieced on days 7 and 42. The bursa was collected, fixed, and processed for histomorphometric assessment using a Kontrom KS 400 image analyzer. Data were analyzed by Biostat 3.0 (Tukey Test). The results of average cortical area percentage in bursal follicles of 6-week-old birds were 45.12a (10 birds/m²), 30.43b (15 birds/m²), and 23.77b (20 birds/m²). Average body weight was 2.58a kg (10 birds/m²), 2.56a Kg (15 birds/m²), and 2.47b Kg (20 birds/m²), respectively. The percentage of foot-pad dermatitis in 6-week-old birds was 3.33a (10 birds/m²), 17.76b (15 birds/m²), and 49.17c (20 birds/m²). These differences were statistically significant at a P 0.05 level. Under these experimental conditions,, it was concluded that the best stocking density to produce broilers is between 10-15 birds per square meter.