Reproductive performance is normally poorer for herds during the summer months. This is especially the case for outdoor herds where the effect of increased temperatures can have a negative impact upon breeding performance.

Typically, increased returns are apparent for summer services (July to September) with litter size to services during this period also being lower. In addition, increased concerns with sows showing delayed returns to heat post weaning can further complicate service routine. So how can we try and minimise the risks of summer associated infertility.

Adrian Cox

• Older sows tend to show greater problems with returns than smaller females. Increasing gilt intake to the herd during the at-risk period will help to reduce the risks of reduced farrowings in the autumn. For those units that produce their own gilts, review the level of dam line matings being undertaken to ensure adequate gilt availability for next summer.
  
  
• Keeping sows and gilts in sensible working body condition rather than getting too fit.
  
  
• Ensure the provision of wallows to outdoor sows and try and keep indoor sows cooler – by reducing bedding and employing misters or fans for air movement – will help encourage better breeding performance.
  
  
• Ensure that sows are working hard in lactation so that when weaned, there is a good return to heat triggered by a sudden reduction in milk demand. This can be especially problematic with outdoor sows where normal suckling of litters is compromised by piglets running and sows lying in wallows etc.
  
  
• Boar semen quality is often poorer during the summer months. Ensure sufficient availability of AI semen is available to serve sows and returns too if catch boars are not working effectively.
  
  
• Double-check that semen storage cabinets are working effectively in summer temperatures – in reality, ongoing checking of these cabinets should be the norm.
  
  
• Because sows can show more variability in coming back onto heat in the summer, ensure that your serving regime is reviewed to ensure that sows are only served when properly on heat, not when it is convenient! Consider undertaking an oestrus survey to confirm that timing of AI is correct. (Contact your JSR representative or vet to discuss this if uncertain.)
  
  
• With more units now having pig only staff, the potential reduced input to the pig unit during harvest is less than previously. Nonetheless, ensure that despite the excitement of combines working the pig unit continues to be correctly staffed/managed.