PRESENCE OF BACTERIOPHAGES IN ANIMAL FEED AS INDICATORS OF FECAL CONTAMINATION

Abstract

The objectives of this study were to determine if indigenous male specific and somatic bacteriophages could be detected in animal feeds and if isolated phages contained RNA or DNA. Seven fresh feeds, 2 fresh feed ingredients, 7 stored feeds, 2 stored feed ingredients, and 8 samples of poultry diets suspected to contain Salmonella spp. were enriched and spot plated for indigenous phages using Escherichia coli Famp and CN-13 as hosts. Bacteriophage numbers were below detection without enrichment, but both male specific and somatic coliphages were detected in all animal feeds, feed ingredients, and poultry diets after 16 h of enrichment, even after the samples had been stored for 14 months of storage at − 20 C. Five out of 9 fresh feeds and 7 out of 8 stored feeds contained RNA somatic phages.

Keywords:

• Animal feeds
• Poultry diets
• Feed ingredients bacteriophages
• Detection

ACKNOWLEDGMENTS

This research was supported the Texas Higher Education Coordinating Board's Advanced Technology Program (Grant# 999902–165), TEX08239 project, and Hatch grant H8311 administered by the Texas Agricultural Experiment Station. K.G.M. was supported by a Pilgrim's Pride endowed graduate fellowship and a Heep Foundation Internship. The authors would like to thank Dr. F.T. Jones (Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701) and K. Richardson (Anitox Corporation, Buford, GA 30519) for their assistance.