Effects of in-feed egg yolk antibodies on Salmonella shedding, bacterial antibiotic resistance, and health of pigs.
To determine effects of anti-Salmonella egg yolk antibodies on shedding and antibiotic resistance of Salmonella enterica Typhimurium, newly weaned pigs were randomly assigned to six dietary treatments. These treatment groups were (i) a control (basal) diet without additives and similar diets with (ii) egg yolk powder derived from chickens challenged with Salmonella Typhimurium antigens, (iii) a commercial egg yolk powder control, (iv) apramycin for 14 days followed by carbadox, (v) oxytetracycline, or (vi) spray-dried plasma protein. Treatments were provided beginning on day 3 of the trial, and all pigs were challenged with 5 ml of 10(8) CFU/ml Salmonella Typhimurium on day 7. Fecal samples were collected on days 0, 7, 8, 12, 14, 21, 58, 88, and 118 for isolation of Salmonella and Escherichia coli to determine shedding and antibiotic resistance patterns. Body weights, white blood cell counts, and plasma concentrations of anti-Salmonella immunoglobulin G and porcine interleukin 1beta were analyzed as indicators of animal health. The percentage of pigs shedding Salmonella was lower for antibiotic treatment groups compared with other groups; however, resistance was greater in E. coli from pigs fed antibiotics than in pigs in other treatment groups. Health and performance indicators (pig weight gains, white blood cell counts, and plasma concentrations of anti-Salmonella antibodies) did not differ between treatment groups. These studies indicate that feeding egg yolk containing anti-Salmonella immunoglobulin Y may not be effective in controlling shedding of Salmonella in pigs.
Department of Animal Science, University of Tennessee, Knoxville, Tennessee 37996, USA. amathew@utk.edu
Alan G
AG
Mathew
Sukanya
S
Rattanatabtimtong
Charles M
CM
Nyachoti
Lin
L
Fang
D000821:Animal Feed; D000818:Animals; D000907:Antibodies, Bacterial / Q000008:administration & dosage*; D015169:Colony Count, Microbial; D024881:Drug Resistance, Bacterial; D004530:Egg Yolk / Q000276:immunology / Q000382:microbiology; D004926:Escherichia coli / Q000254:growth & development; D005243:Feces / Q000382:microbiology*; D007958:Leukocyte Count / Q000662:veterinary; D011897:Random Allocation; D012475:Salmonella / Q000254:growth & development* / Q000276:immunology; D012481:Salmonella Infections, Animal / Q000517:prevention & control; D012486:Salmonella typhimurium / Q000254:growth & development*; D013552:Swine / Q000254:growth & development / Q000382:microbiology*; D013553:Swine Diseases / Q000517:prevention & control; D015430:Weight Gain
D000907:Antibodies, Bacterial