Beziehung zwischen mittels Dualenergie-Röntgenabsorptiometrie bestimmter Körperzusammensetzung und Fruchtbarkeit von Jungsauen

Abstract. Title of the paper: Relationship between body composition measured by dual energy x-ray absorptiometry and reproduction performance in gilts
This study was conducted to evaluate the relationship between body composition and reproduction traits in gilts. A number of 176 gilts of different genotypes were categorized in three different groups. Group 0 consists of gilts that were disqualified for breeding according performance test results or showed no occurrence of oestrus. Group 1 consists of all gilts, which farrowed after an artificially insemination. Group 2 was composed of gilts that were artificially inseminated but did not give birth to a litter.

Body composition was determined in vivo using dual energy x-ray absorptiometry at a live weight of about 90 kg. Initial reproduction data from group 1 were also evaluated.

Results of the performance test showed considerable variation among the different groups. Group 1 was significantly heavier and the daily gain was significantly higher than in group 0. However, results of breeding index and value were clearly below the results of the other two groups. The body fat content was significantly higher in gilts with a litter (>1.65 absolutely) than in gilts without a litter (group 2) and in disqualified gilts (group 0). Group 2 gilts showed the smallest body fat mass. However, the relation between DXA fat percentage and litter size for group 1 showed in tendency that the litter size might decrease with an increasing fat content of gilts. Therefore, an optimum body fat content for conventional breeding gilts of European or American origin needs to be determined for a maximum fertility.