Lactating sows have extreme nutritional demands during the 3-4 week nursing period. Adequate feed provision and housing conditions determine sow welfare during this critical phase.
Lactating sow welfare is determined primarily by the balance between nutritional intake and the extreme metabolic demands of milk production. Sows losing more than 1 unit of body condition during lactation struggle to return to oestrus promptly and experience poorer subsequent reproductive performance. Hot farrowing rooms reduce appetite and worsen this nutritional deficit. Ad libitum wet feeding systems that maximise voluntary feed intake and farrowing rooms kept below 20 degrees C with supplementary cooling maintain sow welfare and reproductive performance simultaneously.