Effects of cloprostenol sodium and carbetocin on synchronous parturition and colostrum composition in large white sows.

Background: Synchronized parturition is essential for optimizing batch production and implementing effective "all-in/all-out" management strategies. However, the efficacy of exogenous hormones in regulating parturition and the potential adverse effects of parturition induction have remained inconsistent. This study investigates the impact of cloprostenol sodium and carbetocin on farrowing performance in sows, aiming to establish an optimal induction protocol.

Results: Initially, based on a dataset comprising 3,657 gestation records of large white sows, we calculated the average gestation length for the herd to be 114 days, and the induction time was set at 113 days of gestation. Subsequently, parturition was induced in 546 primiparous sows and 339 multiparous sows, respectively. The experiment consisted of three groups: (1) CON group (control), (2) PG group (cloprostenol sodium), and (3) PGCAR group (combination of cloprostenol sodium and carbetocin). In primiparous sows, compared to the control group, the PG group exhibited farrowing rates of 23.5% on day 113 and 71.8% on day 114. Notably, the PGCAR group demonstrated a higher farrowing rate of 78.1% on day 114. Importantly, the working hours farrowing rate for the PGCAR group was 90.3%, with 64.6% of sows farrowing within five hours after carbetocin administration. Additionally, both the PG and PGCAR groups showed a significant reduction in farrowing duration, birth interval, and stillbirth rate compared to the control group. Similar trends were observed in multiparous sows. In the PG group, farrowing rates were 25.0% on day 113 and 66.7% on day 114. Notably, the PGCAR group demonstrated a farrowing rate of 76.2% on day 114. Specifically, within the PGCAR group, 87.7% of farrowing events occurred during working hours, and 68.0% of farrowing events occurred within five hours following carbetocin administration. Furthermore, compared to the control group, the PGCAR group of multiparous sows exhibited a significant reduction in both farrowing duration and birth intervals. Furthermore, our analysis revealed no statistically significant differences in colostrum composition and milk bioactive components across the CON, PG, and PGCAR groups.

Conclusions: The combined administration of cloprostenol sodium and carbetocin effectively induces parturition in large white sows, accelerating the parturition process without adverse effects on either the sows or the piglets. However, 5-22% of the sows in this study exhibited spontaneous farrowing prior to hormone-induced parturition. Further investigation is necessary to elucidate the underlying mechanisms and address instances where sows initiate farrowing prematurely before induction.