The Effects of Proliferative Enteropathy on Pig Growth and Body Composition

Abstract

Proliferative Enteropathy is caused by L. intracellularis and can have a great economic impact on pig farms. Disease can lead to reduced weight gain and feed intake and an increased feed:gain ratio. The objective of this experiment was to investigate the effects of L. intracellularis on growth performance and body composition. 36 Male pigs were housed individually with food and water available ad libitum and half of them were inoculated with L. intracellularis at 9 weeks of age. All control pigs were negative before and during the trial and all the pigs in the L. intracellularis group were positive on PCR and/or serology during the trial. Weights and feed intake were weekly recorded and the pigs were scanned with a CT-scanner at day -14, day 21 and day 42 post inoculation (PI). The results were categorized into a pre-infection period (-18 to 3 days PI), early infection period (3-24 days PI) and a late infection period (24-42 days PI). Pigs infected with L. intracellularis did show a reduced weight gain during early infection, and a reduced feed intake during both early infection and late infection, but these differences between treatment groups weren’t significant. However, there was a significant difference between treatments in variation in weight gains within the group, during early infection. There were no significant differences in the proportion of different body tissues between treatment groups or between scans. We did see a reduced muscle and fat growth in pigs infected with L. intracellularis, but this wasn’t significantly different from the control group. We also found a reduced P2 back fat score in pigs infected with L. intracellularis, but these weren’t significantly different from the mean of the control group. This study show that infection with L. intracellularis doesn’t changes body composition in the pig, but it does give reduced growth and a large variation within an infected group. Further research is needed to find out why some pigs are better protected for the effects of L. intracellularis infection than other pigs.