Pigs have relatively few sweat glands and therefore quickly encounter problems during heat periods. They are unable to dissipate heat efficiently.
To minimize the effects of heat on pigs, a targeted approach is necessary. Adjusted feeding is a key lever in this regard.
Practical Effects of Heat Stress
One of the first observable signs of heat stress is a significant decrease in feed intake. At high temperatures, pigs voluntarily reduce feed intake to minimize the heat generated by digestion (thermal energy).
The consequences are widespread performance losses: Growing pigs show reduced daily weight gain and longer fattening periods due to decreased feed intake. Feed conversion also deteriorates, as a larger proportion of the absorbed energy is needed for maintenance and cooling processes.
Heat stress measurably costs livestock farmers production performance – in growth, feed conversion, and reproduction.
Effects on Sow Fertility and Piglets
Heat stress is particularly critical for breeding sows, as it affects not only the health of the mother animal but also piglet development. Lactating sows during heat periods often enter an energy deficit state: Due to declining feed intake, they must increasingly mobilize body reserves (fat deposits) for milk production.
High weight loss in sows during lactation (over 20 kg) negatively impacts fertility. Furthermore, heat stress increasingly leads to reduced milk production: Lactating sows produce less milk, which directly impairs piglet growth.
Reduced milk production in sows
Lower weaning weights in the litter
Higher susceptibility to diarrhea
In short: Heat stress affects almost all performance and health parameters in pig production – from growth and feed conversion to reproduction, disease resistance, and animal welfare.
Feeding Against the Energy Gap
To prevent the sow from producing unnecessary digestive heat, a portion of the starch in the ration should be replaced by fat as an energy source. This allows performance to be kept consistently high. It is also always important to ensure an adequate supply of hygienically sound drinking water.
- Replace starch with fat as an energy source (e.g., BEWI®-SPRAY LeciBoost or BEWI®-SPRAY 80 L)
- Supplement litter with high-quality piglet milk (e.g., BEWI®-MILK Piglet Premium)
- Electrolyte-containing feed additives for piglets (e.g., BEWI®-SAN Piglet Power)
- Provide sufficient fresh, cool drinking water
The result: Piglets are more vital and healthier, contributing to increased efficiency in piglet rearing.
How to Recognize Heat Stress in Pigs
Preventive Measures
In addition to adjusting feeding, there are other important key levers to prevent heat stress:
01
Optimized Stable Climate
Ventilation, evaporative cooling, or air conditioning can lower stable temperatures.
02
Drinking Water
Pigs must have access to fresh, cool water at all times. Check quality and availability.
03
Feeding Adjustment
Energy and nutrient-rich rations with lower heat load. Shift feeding times to early morning and late evening hours.
04
Housing Management
Cooling zones, e.g., through wet lying areas or spray systems, improve animal welfare.
Conclusion
Heat stress is a serious problem in pig farming that equally affects performance, health, and animal welfare. Through targeted adjustment of feeding – especially the use of energy-rich fat components and the support of piglets with milk replacers and electrolytes – the negative effects can be significantly reduced.
