Feeding behaviour traits recorded during gestation are heritable even though feed intake itself is restricted

Data obtained from electronic sow feeders during the gestation period were used to investigate feed intake and feeding behaviour traits from 3785 predominantly (89.9%) F1 sows. Estimates of heritability, permanent environmental effect of the sow and phenotypic variance were obtained for seven distinct time periods during gestation for average feed intake (AFI), daily time spent eating (AFT), rate of feed consumption (AFR), the number of feeding events (AFE) and total born (TB) piglets. As expected, heritability estimates for feed intake traits such as AFI1-AFI7 were not different from zero, which can be explained by the restricted feed allocation (rather than ad libitum feeding). In the same time periods, heritabilities for the amount of time sows spent eating were low to moderate: lowest at the beginning (0.12±0.03) and at the end of gestation (0.16±0.04) and highest in the middle of gestation (range: 0.16 to 0.27). The same pattern was found for the rate of feed consumption. Further investigation of these feeding behaviour traits is warranted with respect to their associations with reproductive performance outcomes, given that they represent potential limitations to sows' ability to consistently meet their nutritional requirements over time.