Effect Of Backfat Thickness On Reproductive Performance Of Gilt

The purpose of this article/experiments is to study the relationship between backfat thickness and production performance of gilt.180(Landrace×Yorkshire)gilt were used in our experiments,which were divided into three groups: normal feeding group,30% reduction feeding group and 30% increase feeding group.Using the American(Renco)Lean-meter backfat tester,the pig P2 point,the last rib distance from the midline 6.5cm,was selected to measure gilt pregnancy 30 d,60 d,90 d and prenatal backfat thickness.The number of litter size,number of dead births and litter weight were recorded.The effects of different nutritional levels on backfat thickness and production performance and the effects of thickness of backfat on production performance were analyzed.Effects of different nutritional levels on backfat thickness and production performance: Compared with the normal feeding group,the 30-day,60-day,90-day and prenatal backfat thickness decreased by 24.27%,22.22%,21.89% and 22.84% respectively in the 30-day,60-day,90-day feeding group,with significant differences in the number of litter heads,dead fetus heads,litter weight.The difference was 8.29%,12.12% and 7.86% respectively,and the difference was significant.Compared with the normal feeding group,the 30% feeding group had 20.19%,18.04%,16.02% and 15.18% higher backfat thickness at 30 days,60 days,90 days and 15.18% respectively.The difference was significant.The number of litter heads and litter weights decreased by 6.91% and 11.57%,respectively.The number of dead fetuses increased by 81.82%,and the difference was significant.The difference is remarkable.According to Fisher’s optimal segmentation method,180 sows were divided into three groups: middle backfat,low backfat and high backfat at 30,60,90 and prenatal stages respectively.(The middle backfat group was the best production performance interval)The results showed that the backfat thickness was 14-19 mm on the 30 th day of pregnancy,17-19 mm on the 60 th day of pregnancy,19-22 mm on the 90 th day of pregnancy and 21-24 mm on the prenatal backfat thickness were the best.The results showed that the backfat thickness and production performance were affected by the different feeding amount.The backfat thickness,litter size,stillbirth head number and litter weight were significantly decreased in reduce 30% feeding amount group and increase 30% feeding amount group.Backfat thickness of gilt at different stages is related to production performance,too thinner or too thicker backfat thickness reduced production performance,especially excessive backfat not only reduces production performance but also wastes feed and increases the cost of breeding.