The objectives of this experiment were to determine the effects of high oil corn (HOC) on the aerosol transmission of the porcine reproductive and respiratory synrome virus (PRRSV), and the effects of HOC on PRRSV seroconversion in growing pigs. One hundred PRRSV negative gilts (25 kg) were housed in 1 of 2 mirror imaged rooms. Both rooms contained 10 pens with 5 pigs/pen, and each room had its own separate ventilation and maure handling systems. The study was arranged in a 2 x 2 factorial arrangement. The main effects consisted of a dietary energy source, (#2 yellow corn (CON) and HOC), and with or without a virus challenge (VC). A three-phase feeding prgram was used, and in each phase the CON nd HOC diets contained the same lysine:calorie ratios. Animals were allowed to acclimate ot their respective diets for two weeks before the VC was administered At day 14, fifty pigs (pigs from 5 pens in each room) were inculated with a tissue culture infectious does (TCID) 50 of PRRS virus 2367 (1 x 104) intranasally. Blood was collected twice weely from day 7 to day 64 post-inculation (PI) and analyzed for serum PRRSV concentrations via ELISA PRRSV serum antibody titers peaked for all treatments at day 50, and then declined thereafter Serum antibody titers remained lower (P=.05) for animals fed HOC diet compared to those fed the CON diet. Animals fed the HOC diet experienced a delay (P=03) in measurable PRRSV serum antibody titers compared to those fed the CON diet. Also, it took longer for the PRRSV negative pigs fed HOC to seroconvert than the PRRSV negative pigs fed the CON diet. This dely may be attributed to effects of HOC on dust reduction affecting the aerosol transmission of PRRSV, and/or the biological effect HOC has on PRRSV, and/or the biological effect HOC has on PRRSV challenged pigs. The data from this study indicates that HOC delays the seroconversion of PRRSV challenged pigs, and may reduce the onse of PRRSV in growing pigs.
Number of Pages
South Dakota State University
Copyright © 2001
Christopherson, B.T.; Thaler, R.C.; Chase, C.C.; and Pohl, S.H., "Efficacy of High Oil Corn in Reducing the Severity
of a PRRSV Challenge in Growing Pigs" (2002). South Dakota Swine Research Report, 2001. 24.