Manitoba Agriculture, Food and Rural Initiatives

Return to Estrous Delayed?

Ron Bazylo, Swan River

After weaning, sows should return into heat within 5 to 6.5 days. If they do not, breeding management becomes more difficult. In most cases sows are weaned on Thursdays, and all breedings are done the following Monday, Tuesday or Wednesday.

One factor that determines if sows come into heat in time is the lactation diet. Failing to exhibit heat within the time frame, usually results from a lack of energy intake, This may be caused by feeding a low energy diet or from lack of feed consumption. The first problem can be easily rectified by adding additional wheat to the diet to increase the energy. If feed consumption is low, check you water supply. Flow rate should be at least two liters per minute. Ensure farrowing temperatures are not too high which also reduces feed consumption.

First litter gilts usually take longer to return to estrous. Therefore, use cross fostering when possible. Eight piglets per gilt is plenty. Another good idea is to wean your first litter gilt on Mondays, three days earlier than sows. This gives them three extra days to return into heat. First litter gilts require a higher energy diet since their consumption is lower. Additional oil may be used to increase the energy density.

For more information on lactation diets or on breeding management contact your nearest swine specialist.