Relationship between serum β-lactoglobulin content during gestation and reproductive efficiency in primiparous sows

The relationship between β-lactoglobulin (β-LG) serum concentration in sows during the last 8 weeks of gestation and subsequent piglet performance was investigated in 10 Dunel gilts. Two classes of gilts were identified with low ( 150 ng/ml) average serum β-LG content. For both low and high content groups, equations were calculated to describe trends in serum β-LG content, respectively y1=10.07e0.0237x (R2=0.3122) and y2=69.00e0.0201x (R2=0.6959), where x is the number of days of gestation. Differences in serum β-LG content between the two groups were highly significant at all weeks (P 0.05) between groups were shown for total number of piglets born, born alive, stillborn or mummified and piglet survival rates up until d 21 after farrowing. The group with high serum β-LG content during gestation showed higher litter weights at d 5 (P<0.05) and d 21 (P<0.10) and higher estimated milk production from farrowing to d 5 (P<0.10). The results indicate that serum β-LG content during the final weeks of gestation could be used as an early indicator of reproductive efficiency, and that gilts with high content could be selected to improve herd productivity.