Investigation of some Reproductive Parameters in Primiparous Sows from the East Balkan Breed After Farrowing During the Spring and Winter Season

The purpose of the present investigation was to evaluate the effect of farrowing season upon some reproductive parameters in primiparous sows from the East Balkan breed and their progeny. Twelve East Balkan primiparous sows were included in the study – six aged 363±35 days weighing 82±6 kg, that farrowed during the spring (March-April) and another six, 750±7 days of age, weighing 89±11 kg, farrowed during the winter (November and December) and their progeny. The following reproduction parameters were determined: pregnancy duration, farrowing time, litter size, live born piglets per litter, birth interval, live birth weight of piglets and birth to first suckling interval. The results demonstrated that the number of live born piglets and their live birth weights from spring litters (4.50±0.6 and 0.90±0.1 kg) were higher (P < 0.05) than those of winter litter (3.00±0.9 and 0.84±0.1 kg) whereas the birth to first suckling interval during the spring was statistically significantly shorter (7.8±3.2 min; P < 0.05) compared to the respective winter interval (9.6±1.4 min). In conclusion, the farrowing season had an effect on live birth weight of East Balkan piglets, their vitality and birth to first suckling intervals. The study results could be used in strategies for reproductive management improvement in sows reared in organic conditions.