Effect of porcine parvovirus serostatus on the reproductive performance of mated gilts in an infected herd.

Gifts from 2 commercial swine operations (farm A and farm B) that were bred each week were tested for porcine parvovirus antibody. On farm A, 21.9% (weekly, 2% to 35%) of the 657 gilts tested over a 16-week period were seronegative within 1 week of mating. On farm B, 17.7% (weekly, o to 40%) of the 164 gilts tested over a 10 week period were seronegative within 1 week of mating. Eighty-one gilts from farm A which were seronegative at time of mating were retested at the end of the gestation. Of the 81 gilts, 4 1 had developed antibody titers. The litter size decreased by 1.3 live pigs/litter. The percentage of small litters (less than or equal to 6 born alive) in the group that seroconverted was 36.6% compared with 10% in the gilts that remained seronegative throughout gestation.