Authors : J.A. Loughmiller , S.S. Dritz , J.L. Nelssen and M.D. Tokach
Abstract: Forty seven pigs (30?1 kg) were used to determine the effects of acute Actinobacillus pleuropneumoniae challenge on growth, N balance, acute phase proteins, plasma IGF-I and carcass characteristics. Pigs were challenged (APP; n=30; intranasally 5?10 cfu) on d 0, unchallenged and fed ad libitum (AL; n=7), or unchallenged and pair-fed the feed intake of a challenged pig (PF; n=10). Mortality was 23% for APP, but none occurred in unchallenged groups. A treatment?time interaction was observed for serum haptoglobin (p<0.01) which was higher for APP vs AL and PF on d 1 and 5. Plasma IGF-I (treatment and quadratic time effects, p<0.03) was lowest on d 1 for APP vs AL and PF (p<0.01). The IGF-I levels tended to remain lower for APP than for AL, but not PF, through d 9 (p<0.10). Treatment and linear time effects were observed (p<0.05) for ADG, which was lower (p<0.01) for APP vs AL from d 0 to 3. Lower ADG was observed from d 4 to 7 for PF vs APP (p<0.06) and PF vs AL (p<0.04). Day 0 to 17 ADG was higher for AL vs APP and PF (p<0.03). Treatment did not affect G/F (p>0.10). A treatment?time interaction was observed for N retained (p<0.05). Greater N retention was observed for AL vs APP (p<0.01) from d 0 to 7. Results indicate that growth and N balance reductions resulted from reduced ADFI and increased endogenous N losses. Reductions were primarily short-term, because growth performance and N retention recovered by d 14 after challenge.
J.A. Loughmiller , S.S. Dritz , J.L. Nelssen and M.D. Tokach , 2005. Effects of an Actinobacillus pleuropneumoniae Challenge on Growth, Nitrogen Balance, Insulin-like Growth Factor-I, Acute Phase Proteins and Final Body Composition of Swine . Journal of Animal and Veterinary Advances, 4: 805-817.