Effects of the Physical Form of Diet on the Outcome of an Artificial Salmonella Infection in Broilers

To prove the hypothesis that the physical form of diet affects the outcome of an artificial infection with Salmonella Enteritidis in broilers, 7-day-old birds were allotted to one of four groups and fed botanically, and nearly also chemically identical diets, differing in grinding and further compaction. In total, two birds from each group (age 14 days) were administered on average 1.06 × 108 colony-forming units (CFU) of Salmonella Enteritidis directly into the crop by gavage and immediately put back as “seeder birds” into their respective groups. The salmonella status of each bird was analyzed by cloacal swabs, and at postmortem examination, cecal content and liver tissue samples were taken. Shedding (measured by cloacal swabs) was reduced significantly (P < 0.05) in groups offered the coarsely ground and pelleted diet and the diet including whole wheat compared with the groups fed the finely ground and pelleted and the coarsely ground and extruded diet. Nevertheless, only broilers fed the diet containing whole wheat showed a significantly (P < 0.05) lower frequency of Salmonella Enteritidis isolation in the cecal content and liver tissue. This diet was characterized by the highest percentage of particles >2 mm. In this study the physical form of diet affected the outcome of an artificial infection with Salmonella Enteritidis significantly. Efectos de la forma física de la dieta en la infección artificial por Salmonella en pollos de engorde. Para probar la hipótesis de que la forma física de la dieta afecta el resultado de una infección artificial con Salmonella Enteritidis en pollos de engorde, aves de siete días de edad fueron asignadas en uno de cuatro grupos alimentados con dietas botánicamente idénticas y casi idénticas químicamente, con diferencias en la molienda y compactación posterior. En total, a dos aves de cada grupo (con edad de 14 días) se les administró una media de 1.06 × 108 unidades formadoras de colonias (UFC) de Salmonella Enteritidis (SE) directamente en el ingluvíes a través de una sonda y de inmediato se introdujeron como “aves sembradoras” en su grupos respectivos. La condición con relación a salmonella de cada ave se analizó mediante hisopos cloacales y durante el examen post mortem se tomaron el contenido cecal y muestras de tejido del hígado. La eliminación (determinada mediante hisopos de cloaca) se redujo significativamente (P