Effect of Porcine Circovirus Type 2 Vaccination of Sows on Selected Production Parameters

An aim of the study was to evaluate the efficacy of Circovac vaccine in two Polish pig herds affected by post-weaning multisystemic wasting syndrome (PMWS) and reproductive failure. The effectiveness of vaccination was assessed indirectly by analysis of production performance of the examined herds. It was found that Circovac is extremely efficient in reducing losses attributed to PMWS and controlling the disease. Analysis of production parameters after vaccination showed significant improvement in the nursery and finishing sectors. Post-weaning mortality dropped nearly five times in herd P and 2.5 times in herd D. Mortality among fatteners decreased by half in both herds. Additionally, significant improvement was observed concerning average daily weight gains of weaners and fatteners. Despite the considerable benefits of vaccination in nursery and finishing pigs, a tendency to increase reproductive parameters was observed. The most striking differences concerned returns to oestrus and abortion rates, which reached more favourable levels even compared to the period before the PMWS episode. This observation suggests that subclinical infections with PCV2 may have negative effects on the reproduction.