Adequate sow body condition scores during gestation may enable quicker return to estrus post-weaning, according to Mike Hemann, Great Lakes Region swine nutritionist for Purina Animal Nutrition LLC, who said that sow rations should be formulated so body condition scores remain steady through the production cycle.

Producers should maintain a score of 2.9 to 3 on a scale of 1 to 5 within their sow herds, according to Hemann. Sows with a score of 3 will have backfat measurements of 0.59 to 0.86 inches and the sow’s ribs, hips and backbone will be able to be felt with firm pressure but not observed visually. “Nutrition comes into play in a big way when we look at herd health and sow longevity,” he said. “Feeding sows so they have consistent, healthy body condition scores can improve longevity and help the sow become capable of producing 30 full potential pigs in one year.”

Along with the potential for improved birth weights and higher productivity in lactation, Hemann said that sows in ideal body condition may return to estrus quicker post-weaning. Reducing the days between weaning and estrus can then influence efficiency within the herd by helping the sow move onto her next litter quicker. “We want to try to reduce the days to return to estrus as much as possible and get that number as close together in the group of sows as we can,” said Hemann. “Keeping that number low and individual body condition scores steady comes from managing nutritional intake during lactation and then making sure sows are not under-conditioned going into the breeding barn."


The most efficient sows will return to estrus in four-and-a-half to five days on average post-weaning, according to Hemann. In addition to proper nutrition, routine body condition scoring protocol can promote consistent condition. Herds that have consistent body condition scores typically have one or two people trained in the process whose focus is routine score evaluation. These employees are responsible for adjusting feed drops in gestation and managing feed intake in order to promote and maintain ideal body condition scores. 

“A good way to manage this is to divide the herd into four groups,” said Hemann. “Each week one group is evaluated for BCS, allowing all sows in the herd to be evaluated on a monthly basis for BCS by the assigned employees.” Hemann said he encourages managers to post a list of the sows to be evaluated in the farm office on a weekly basis to keep the process top of mind. After evaluating the condition of the sows, rations can be adjusted accordingly so ideal body condition scores are maintained through all production stages. 

“The key to consistent productivity is to maintain adequate body condition in gestation, to return sows to ideal body condition as soon as possible after breeding and then to maximize intake during lactation,” he said. “One way to promote and help maintain consistent [body condition scores] is to have fresh feed in front of sows at all times and then to stimulate them to eat several times per day during the lactation period. Properly conditioned sows are better able to care for their litters, will come out of lactation in better condition and may return to estrus quicker."