Lactation is the most nutritionally demanding period for sows, and inadequate nutrition during this phase harms sow health, piglet growth, and future reproductive performance.
Lactating sow welfare centers on the physiological burden of supporting both her own maintenance and milk production for a large litter. A sow nursing 12-14 piglets is under enormous metabolic strain, and inadequate nutrition during this period creates a cascade of welfare and reproductive consequences. Excessive body condition loss during lactation is not merely a production concern - it reflects the sow drawing on her own tissue reserves to maintain milk supply, with associated metabolic stress, weakness, and increased susceptibility to disease. High temperature is a particularly challenging environmental factor in intensive systems: heat stress suppresses feed intake at exactly the time when nutritional demands are highest. The transition from lactation to pregnancy is physiologically sensitive - sows that enter their next pregnancy in poor body condition face compromised embryo implantation and litter size, meaning lactation nutrition affects two generations simultaneously.