饲喂频率对妊娠母猪背膘厚和繁殖性能的影响

目的] 研究饲喂频率对妊娠母猪背膘厚和繁殖性能的影响。方法] 挑选加系杜洛克经产母猪480头,配种时按照胎次（2~7胎）、背膘厚（11~22 mm）相近的原则随机将母猪分为T1组（每天饲喂1次）和T2组（每天饲喂2次）,两组每天等量饲喂。T1组母猪220头,饲喂时间为8：00;T2组母猪260头,饲喂时间为8：00和15：00,每次饲喂量为总量的一半,定位栏饲养。结果] ①饲喂频率不影响妊娠56 d、开配-妊娠56 d的背膘厚（妊娠56 d背膘厚-开配背膘厚）（P>0.05）;T2组妊娠110 d（P=0.06）、妊娠56-110 d（P=0.09）背膘厚（妊娠110 d背膘厚-妊娠56 d背膘厚）有高于T1组的趋势。②饲喂频率对窝产总仔数、活仔数、死胎数、木乃伊胎数、初生窝重以及初生个体重均无显著（P>0.05）影响。③在三胎母猪中,T2组妊娠110 d（P=0.01）、妊娠56-110 d（P=0.04）背膘厚均显著高于T1组;五胎及以上母猪,T2组妊娠56-110 d（P=0.08）背膘厚有高于T1组的趋势。④饲喂频率不影响二胎母猪窝产总仔数、死胎数、木乃伊胎数、初生窝重以及初生个体重（P>0.05）,但二胎母猪中T2组活仔数有高于T1组的趋势（P=0.07）。结论] 饲喂频率由每天两餐减少到每天一餐不会对母猪的繁殖性能产生不利影响。

Effects of Feeding Frequency During Gestation on Backfat Thickness and Reproductive Performance of Sows

Objective] To assess the impacts of feeding frequency on backfat thickness and reproductive performance in pregnant sows. Method] A total of 480 multiparous Duroc sows were selected and randomly divided into two groups （T1 and T2） according to the principle of similar parity （2^nd -7^th） and backfat thickness （11-22 mm） before artificial insemination （AI）. T1 group sows （n=220） fed once per day, and the feeding time was 8:00. T2 group sows （n=260） fed twice per day, and the feeding time was 8:00 and 15:00, respectively, with half of the total amount of diet each time. Both groups fed the same amount each day. The experimental sows were housed in individual crates.Result] ①Feeding frequency had no significant （P>0.05） effects on backfat thickness on 56^th day of gestation and the difference of backfat thickness between day of AI and 56^th day of gestation （backfat thickness on 56^th day of gestation minus that on day of AI） . A trend of increase in backfat thickness on 110^th day （P=0.06） of gestation and the difference of backfat thickness between 56^th day and 110^th day （P=0.09） of gestation （backfat thickness on 110^th day minus that on 56^th day of gestation） in T2 group was observed in comparison to T1 group. ② There were no significant （P>0.05） effects of feeding frequency on the total number of piglets per litter, number of live piglets, number of stillborn piglets, number of mummified fetus, litter weight at birth, and individual birth weight. ③ For the third-parity sows, backfat thickness on 110^th day （P=0.01） of gestation and the difference of backfat thickness between 56^th day and 110^th day （P=0.04） of gestation in T2 group was significantly higher than those in T1 group. For sows with five and above parities, an increasing trend in the difference of backfat thickness between 56^th day and 110^th day （P=0.08） of gestation in T2 group was also found in comparison to T1 group. ④ Feeding frequency had no significant （P>0.05） effects on second-parity sows in terms of total number of piglets per litter, number of stillborn piglets, number of mummified fetus, litter weight at birth, and individual birth weight, while second-parity sows in T2 group had higher number of live piglets than those in T1 group （P=0.07）. Conclusion] Reducing feeding frequency from twice to once per day had no negative impacts on reproductive performance of sows.