Reproductive performance of first parity sows

Area of Science:

• Animal Science
• Reproductive Biology
• Swine Production

Background:

• First-parity sows are critical for herd replacement.
• Optimizing reproductive efficiency in young sows is economically important.
• The weaning to oestrus interval (WOI) is a key factor in swine reproduction.

Purpose of the Study:

• To investigate the impact of prolonged weaning to oestrus interval (WOI) on the reproductive performance of first-parity sows.
• To determine if delaying mating post-weaning influences subsequent litter size.
• To explore the relationship between extended WOI and ovulation rate.

Main Methods:

• Retrospective analysis of reproductive data from first-parity sows.
• Comparison of second litter size based on varying weaning to oestrus intervals (WOI).
• Evaluation of the effect of deliberately delayed mating (≥12 days post-weaning) on litter size.

Main Results:

• Sows with a WOI exceeding 15 days had significantly larger second litters.
• Intentionally delaying mating until at least 12 days post-weaning resulted in a similar increase in second litter size.
• The observed increase in litter size was not linked to a higher ovulation rate.

Conclusions:

• Prolonging the weaning to oestrus interval in first-parity sows enhances subsequent litter size.
• Strategic delay of mating post-weaning is an effective method to improve reproductive outcomes.
• The benefits of extended WOI on litter size appear to be independent of ovulation rate changes.