Altrenogest treatment effects on the reproductive performance of sows during transition to batch farrowing

Abstract

The synthetic progestin altrenogest (ALT) has been widely used in sow farms to concentrate artificial inseminations (AIs) during the transition of weekly productive flow for the batch farrowing system of 14 or 21 days. The objective of the present study was to investigate the effect of the duration of ALT treatment on the reproductive performance of weaned sows during transition to batch farrowing. Retrospective data was evaluated regarding the reproductive performance of primiparous and multiparous sows that were either not treated (control, n = 165) or treated with 20 mg ALT during 7 days (ALT7, n = 161) or 14 days (ALT14, n = 199) post-weaning. The interval between weaning or the end of ALT supplementation and first AI did not differ among the groups, as well as the percentage of sows inseminated up to 7 or 10 days after the end of treatment or weaning (P ≥ 0.16). There was a tendency for a lower farrowing rate (P = 0.06) in ALT7 (77.2%) when compared to ALT14 (84.5%) and control (86.3%) groups. The total number of piglets born did not differ among groups (P = 0.35). In conclusion, despite the slight delay in the estrus onset, the proportion of estrous sows was not affected, whereas the adjusted farrowing rate was reduced when ALT was administered for 7 days after weaning in multiparous sows during transition to 21 days batch farrowing system.

A Short-Term Altrenogest Treatment Post-weaning Followed by Superovulation Reduces Pregnancy Rates and Embryo Production Efficiency in Multiparous Sows

“…Synchronization-superovulation treatment not only negatively affected pregnancy rates on day 6 of the cycle of sows inseminated during estrus but also decreased the overall pregnancy efficiency, fertilization rate and overall embryo production efficiency by more than 15 percentage points compared to superovulated control sows. Previous studies indicated that a short-term Altrenogest treatment (3-15 days), when administered independently, is effective for grouping the estrus of weaned primiparous and multiparous sows (14,15,40,(51)(52)(53). Moreover, Altrenogest treatment for 14-18 days improved the reproductive performance of gilts by increasing pregnancy and farrowing rates and litter size (35).…”

Use of chorionic gonadotropins during lactation to optimize postpartum sow reproductive performance: a review

“…Thus, using chorionic gonadotropins during lactation may be an alternative to suppress the first post-weaning estrus for a shorter period, allowing the synchronization of the subsequent estrus ( Kirkwood et al, 1999 ; Zemitis et al, 2015 ; Figure 1B ). That would be particularly suitable for herds transitioning from conventional weekly management to batch farrowing ( Corezzolla et al, 2020 ), optimizing labor and facility efficiency.…”

“…Nevertheless, such hormones may be administered to lactating sows, which are in lactation-induced anestrous. That would suppress estrus expression after weaning in the treated sows to mitigate the consequences of early weaning or excessive catabolism ( Zemitis et al, 2015 ; Kemp et al, 2018 ) and may also be potentially used to synchronize the postweaning estrus to homogenize the breeding groups, which is necessary in batch farrowing systems ( Zemitis et al, 2015 ; Corezzolla et al, 2020 ). Furthermore, such treatment might allow AI during lactation, contributing to an increase in the number of litters weaned per female per year ( Hausler et al, 1980 ).…”