Controlling lactation oestrus: The final frontier for breeding herd management

Area of Science:

• Animal Science
• Reproductive Biology
• Swine Production

Background:

• Lactation anoestrus restricts pig production efficiency by limiting farrowing frequency.
• Extending lactation periods negatively impacts sow productivity and profitability.

Purpose of the Study:

• To review the post-partum reproductive development in sows.
• To explore the physiology of lactation anoestrus and strategies for its alleviation.
• To assess the fertility of sows during lactation.

Main Methods:

• Review of existing literature on sow reproductive physiology and lactation anoestrus.
• Analysis of methods to stimulate ovulation during lactation, including altered suckling, boar contact, gonadotrophins, and housing.
• Evaluation of sow fertility when mated during lactation.

Main Results:

• Sows exhibit a significant spontaneous ovulation rate during lactation (24-31%).
• Various interventions (split weaning, boar contact, gonadotrophins, group housing) effectively induce ovulation.
• These methods can decouple sow mating from weaning, reducing lactation length impact.

Conclusions:

• Lactation anoestrus can be overcome, offering flexibility in sow reproductive management.
• Stimulation methods improve reproductive outcomes, shortening weaning-to-oestrus intervals and increasing litter sizes.
• Uncoupling mating from weaning enhances overall pig production efficiency.