Application of Normal Avian Gut Flora by Prolonged Aerosolization onto Turkey Hatching Eggs Naturally Exposed to Salmonella

Abstract

A commercial preparation of normal avian gut flora (NAGF) was aerosolized for an extended period over turkey hatching eggs during pipping and hatching to examine any protective effects against natural exposure to salmonellae. Turkey hatching eggs, produced by salmonellae-infected breeder flocks and hatched in a commercial hatchery with a history of salmonellae contamination, were used in two trials. In Trial 1, four doses of NAGF inoculum per hatching egg were aerosolized through an automated hatcher fogging system during the final 48 hr of the pipping and hatching process. In Trial 2, two doses of NAGF inoculum were aerosolized in a like manner. In both trials, poults were exposed to Salmonella montevideo during hatching, as indicated by samples collected at the time of pull. At day 7, treated poults in both trials were culture negative for salmonellae and control poults were culture positive for salmonellae. In Trial 1, control poults were infected with Salmonella brandenburg, and in Trial 2, control poults were infected with S. montevideo. These studies justify further critical evaluation of the protective effects of prolonged aerosolization of normal avian gut flora during pipping and hatching against salmonellae colonization in turkey poults.