Nonimmunized egg yolk powder can suppress the colonization of Salmonella typhimurium, Escherichia coli O157:H7, and Campylobacter jejuni in laying hens

University of Guelph, Department of Food Science, Guelph, Ontario, Canada N1G 2W1.

If colonized, poultry shed enteric pathogens in the feces. Of those that colonize poultry Salmonella spp., Campylobacter jejuni (C. jejuni), and Escherichia coli (E. coli) O157:H7 are the most concern to the industry. The authors previously discovered that the introduction of 5% dried nonimmunized egg yolk powder in the regular feed could eliminate and prevent Salmonella enteritidis intestinal colonization of laying hens. Hence, the efficacy of nonimmunized dried egg yolk powder supplement in controlling the colonization of laying hens with Salmonella typhimurium (S. typhimurium), C. jejuni, and E. coli O157:H7 was investigated in this study. The 10% (wt/ wt) egg yolk powder eliminated S. typhimurium after 2 wk of feeding and the 5 and 7.5% (wt/wt) supplements significantly (P < 0.05) reduced the frequency of colonization. Similarly, 7.5 and 10% egg yolk powder reduced the colonization of C. jejuni and E. coli O157:H7 significantly (P < 0.05) after 1 wk of feeding. In the prevention trial, pathogen-free chickens were fed supplemented feed (10% egg yolk powder) for 4 wk and were then infected. S. typhimurium was prevented from colonizing the intestine throughout the 4-wk test, and E. coli O157:H7 colonization was delayed for 2 wk. C. jejuni and E. coli O157:H7 populations in the intestine were significantly (P < 0.05) suppressed by egg yolk powder supplementation throughout the test. None of the supplement concentrations affected BW or the mean weight and number of the eggs laid per hen. At the end of the study, the organisms were absent or significantly (P < 0.05) reduced in the intestine, ovary, oviduct, and spleen of hens fed the egg yolk powder treatment. This study indicates that nonimmunized egg yolk powder is able to reduce the frequency of colonization of foodborne pathogens and prevent these organisms from colonizing the intestinal tract. Addition of egg yolk powder to the regular feed at a concentration of 7.5 to 10% (wt/wt) may be a simple means of reducing or inhibiting S. typhimurium, C. jejuni, and E. coli O157:H7 colonization in laying hens.