The investigation of seasonal reproductive disorders in Lithuanian White female pigs.

Despite domestication, the reproductive performance of female pigs can exhibit strong seasonal trends. Reproduction can be affected by the season and breed. So the purpose of our investigation was to analyse the seasonal reproductive performance in Lithuanian White pig breeding farm. The investigation of reproductive performance was carrried out in 2006. The role of porcine parvovirus (PPV), porcine reproductive and respiratory syndrome virus (PRRSV), Aujeszky’s disease virus (ADV), classical swine fever virus (CSFV), bovine viral diarrhea virus (BVDV), porcine cirvovirus 2 (PCV2), Chlamydiaceae (Chlamydia suis and Chlamydophila abortus infections in reproductive failure was not detected using epizootological, serological and molecular biology methods. The seasonal differences in losses due to reproductive disorders were observed. Altogether 3154 pigs were inseminated and 572 (18.1%) returned to oestrus. It was found that 12.9% (97/752), 13.4% (107/796), 16.4% (124/755) and 28.7% (244/851) inseminated pigs returned to oestrus in I, II, III and IV quarters, respectively. Altogether 1956 (85.6%) pigs farrowed and 330 (14.4%) pigs aborted. It was found that 90.0%, 89.1%, 85.5% and 77.8% pigs (farrowings/ confirmed to be pregnant after insemination) farrowed in I, II, III and IV quarters.