Jerome Kerleau

Best practices to manage seasonal infertility

Seasonal infertility is characterized by lower conception and farrowing results in swine occurring in late summer and early fall. It is a multifactorial problem meaning that it needs to be addressed from different directions (microclimate, feed management, reproduction technique). In order to think about practical solutions, it is worth remembering that fertility is related to good follicular development. If the overall management on the farm is not changed to take into account the warmer summer temperature, seasonal infertility will express. The bottom line is that stressed females will deprioritize pregnancy when challenged. We have to keep the sow herd and boars in cool and comfortable conditions, with the goal to keep them eating and
drinking. If the boars are kept in comfortable and cool conditions, the semen quality should remain optimal. In order to have optimal follicular development, the negative impact of heat should be diminished to the maximum inside the barns, the feed intake has to remain optimal and the boar exposure has to be correctly organized.

Mitigate the effects of heat

  • make 100% sure that the animals have enough fresh quality water available in a constant manner and reduce operations (movements, treatments) in the peak temperature period of the day (10 am – 3 pm)
  • the ventilation systems and the cooling systems (mist, cooling pads) have to work properly in order to minimize the heat stress
  • keep clean the ventilation system (clean the inlets and blades if possible). Dirty ventilation inlets and outlets can lead to major reductions in airflow and thus interfere with the reduction of the temperature in the barns
  • it is possible to supplement the drinking water of the sows with paracetamol around farrowing. Hand spraying the sows with water in the last period of pregnancy will also allow to cool down them
  • it is of course primordial to avoid the effects of heat stress on boars, as the semen quality might be harmed for long period after the stress occurred, and for them air conditioning systems are rational investment that makes sense

Keep the animals eating

  • the sows should have an optimized body condition before farrowing, and we have to help them maintain their condition. Fat sows are more likely to get hot and not eat
  • record the body condition (visual score, back fat, caliper) regularly and adjust the sow feeding norms accordingly
  • when it is too hot, it is not easy to keep the animals eating. So it can be necessary to review the time of feeding (start earlier/finish later in order to feed during the coolest parts of the day) and the frequency of feeding (feed less but more frequently)
  • it is primordial to have first parity sows to eat properly, if they do not eat well, they might have trouble to express estrus after weaning
  • the nutrient profile of the feed can also be reviewed (optimized amino acid profile with less crude protein, more energy in the feed, less raw fiber content). In order to keep the benefit of structural fiber (peristalsis, satiety), innovative non digestible fiber sources can be used during this period

Optimize the reproduction conditions

  • the heat check procedures have to start as early as possible in the morning, with insemination following without delays
  • it is essential to spend the required amount of time to proceed to a correct boar exposure for the gilts and the weaned sows as it has a proven positive influence on follicular development. For each group of 5-6 sows or gilts, there should be a minimum of 5 minutes of quality boar exposure. Make sure that the boars are active and producing a strong smell, this will help to stimulate the follicular growth
  • it can be considered to inseminate sows immediately at first standing reflex, as the estrus-ovulation pattern can be shortened in the summertime
  • the fridge for semen storage should be preventively maintained in order to make sure it provides perfect storage temperature. Install min-max thermometer in the fridge to make sure that the temperature fluctuations are reduced to a minimum. Exposition to the wrong temperature will alter the motility and shelf life of the semen
  • when going to inseminate, take only a minimum required quantity of semen doses and keep them in a cooling box
  • finally, if the layout of the farm allows it, it can be advised to adjust the replacement policy of your farm to have some 10-15% extra gilts available for insemination during the summer period
Those different steps can help your pig farm go through the summer period with minimum negative impact on the sow herd productivity.