Foregoing Sub-therapeutic Antibiotics: the Impact on Broiler Grow-out Operations

We use data from a recent national survey to analyze the use of sub-therapeutic antibiotics (STAs) among broiler growers. We estimate that 42% of growers do not use STAs in their feed or water, and instead rely on a set of other practices, including pathogen testing, expanded sanitary protocols, altered feeding regimens, and Hazard Analysis and Critical Control Point HACCP plans to maintain production. Suspending STAs has no statistically significant impact on production given other inputs, but producers who forego STAs receive higher contract fees, suggesting that they bear higher costs to realize a given level of output. Copyright 2010, Oxford University Press.

Digestibilidade dos aminoácidos do milho, farelo de soja e gérmen integral de milho em galos e frangos de corte cecectomizados Digestibility of amino acids from corn, soybean meal and corn germ meal in cecectomized roosters and broilers

Este experimento foi conduzido para avaliar a digestibilidade dos aminoácidos do milho, farelo de soja e gérmen integral de milho em galos e frangos de corte cecectomizados. Foram utilizados 16 galos Lohmann-LSL com 45 semanas de idade, 40 frangos de corte machos AgRoss 508, sendo 20 com 21 dias de idade e outros 20 com 42 dias de idade, todos cecectomizados. Adotou-se delineamento inteiramente casualizado com três categorias animais (galos; frangos aos 21 dias; e frangos aos 42 dias de idade) para cada alimento avaliado e cada ave considerada uma unidade experimental. O ensaio durou 84 horas: nas 36 horas iniciais, as aves foram submetidas a jejum e nas 48 horas subsequentes, à ingestão forçada dos alimentos, feita com sonda esofágica introduzida diretamente no inglúvio das aves. As excretas produzidas foram colhidas duas vezes ao dia nas 48 horas subseqüentes. Os valores de aminoácidos digestíveis verdadeiros determinados para o milho e gérmen integral de milho determinados com frangos submetidos ao procedimento experimental aos 21 dias de idade foram inferiores aos do grupo controle (galos). Contudo, os mesmos resultados não foram observados para o farelo de soja. O aproveitamento de aminoácidos foi maior nos frangos submetidos ao procedimento experimental aos 42 dias de idade em comparação aos do grupo controle (galos adultos), independentemente do alimento avaliado. O teor de aminoácidos digestíveis verdadeiros totais obtidos foi de 7,24; 6,25 e 7,33% para o milho, 9,66; 9,14 e 9,91% para o gérmen integral de milho e 41,82; 41,78 e 42,02% para o farelo de soja, valores determinados com galos, frangos aos 21 e aos 42 dias de idade, respectivamente. Observou-se que, com o amadurecimento do trato digestório, aumenta o aproveitamento proteico em aves que consomem milho e gérmen integral de milho.<br>This experiment was carried out to evaluate the digestibility of the amino acids from corn, soybean meal and corn germ meal in cecectomized roosters and broilers. The experiment used sixteen Lohmann-LSL roosters with 45 weeks of age, 20 AgRoss 508 male broilers with 21 days of age and 20 other male broilers of same line, with 42 days of age, all of them cecectomized. A completely randomized arrangement with three animal categories (roosters; chickens at 21 and 42 days of age) was adopted for each feedstuff analyzed. Each bird represented an experimental unit. The trial had a duration of 84 hours; in the first 36 hours roosters and chickens were submitted to fasting for intestinal cleaning. After this, birds were forced to ingest 30 grams of each ingredient with an esophageal probe, introduced directly into the crop. During the subsequent 48 hours, the excreta produced was collected twice a day. The values for true digestible amino acids were reduced for corn and full-fat corn germ meal when determined with broilers submitted to the experimental procedures at 21 days of age compared to the control group (adult cockerels). But, the same results were not been observed for soybean meal. In general, the true digestible amino acid values were higher when determined with broilers at 42 days of age compared to adult cockerels. The total amount of true digestible amino acids determined were 7.24; 6.25 and 7.33% for corn, 9.66; 9.14 and 9.91% for corn germ meal and 41.82; 41.78 and 42.02% for soybean meal, values determined with roosters, and broilers at 21 and 42 days of age, respectively. It was observed that as the gastrointestinal tract is mature, the amino acid digestibility of birds that consumed corn and corn germ meal is enhanced