Animal Industry Report

Extension Number

ASL R2808



Summary and Implications

Previous research suggests that enteric disease and gut health interact to decrease pig performance. Our objective was to determine if light birth weight (BRW) pigs or those from the bottom 10th percentile of transition ADG (tADG) have a higher incidence of pathogen presence or enteric lesions than heavier or faster-growing contemporaries. A total of 1,500 pigs were weighed at birth and divided into 5 BRW categories: <1 kg, 1-1.25 kg, 1.26-1.5 kg, 1.51-1.75 kg, >1.76 kg. At weaning, 1,054 random pigs were moved to a commercial wean-to-finish barn. Pigs were weighed individually at 0 and 3 weeks post-weaning. Gain from 0 to 3 weeks post-weaning was calculated and termed tADG. Pigs from 3 tADG percentiles were of interest: 10th, 30th and 70th. Forty pigs from each of the 3 tADG percentiles were matched for sex, litter size, and sow parity, but not BRW to create 20 matched sets totaling 60 pigs. Pigs originated from a herd negative for Porcine Reproductive and Respiratory Syndrome Virus (PRRSV). However, a mixed PRRSV and Influenza A virus outbreak was confirmed week 2 post-weaning. At 3- and 22-weeks post-weaning, pigs were euthanized for organ system tissue evaluation. Lung, lymph node, and digesta were analyzed for presence of various pathogens by PCR and culture methods. Serum and ileal mucosa were analyzed for markers of immunological or oxidative stress. Data were analyzed using PROC CORR, GENMOD, and GLIMMIX, where pig served as the experimental unit. There was no correlation (P > 0.12) between tADG and pathogen presence at either 3- or 22-weeks post-weaning. However, Brachyspira spp. was negatively correlated (P = 0.05; Corr. = -0.881) with birth weight. Neither birth weight (P > 0.54) nor tADG (P > 0.20) affected markers of immunological or oxidative stress in either serum or ileal mucosa at 3- or 22-weeks post-weaning. In summary, poor tADG is not correlated with the pathogens or immunological markers of enteric disease measured in this study.

Copyright Holder

Iowa State University