围产期补喂L-精氨酸对伊犁马母马血液参数、妊娠率、返情率及新生马驹生长的影响

Effects of Supplementary Feeding L-Arginine on Blood Parameters,Pregnancy Rate,Re-Service Rate of Yili Mares during Peripartum and Newborn Foal Growth

本试验旨在探讨在妊娠期最后21 d和分娩后25 d期间补喂L-精氨酸对伊犁马母马血液参数、新生马驹生长以及母马分娩后配种妊娠率与返情率的影响。试验选择30匹年龄、体重、体高、预产期相近的伊犁马母马,分为2组,分别为对照组(n=15)和L-精氨酸组(n=15)。对照组饲喂基础饲粮,L-精氨酸组在基础饲粮配方的基础上添加0.5%L-精氨酸,使每匹马每天L-精氨酸的补喂量达到60 g。母马分娩后12 h内测定马驹体重、体尺参数并统计分娩后配种妊娠率、返情率,同时于试验第0(补喂试验开始前)、21、45天采集母马静脉血样。结果显示:与对照组相比,L-精氨酸组新生马驹体重、体尺参数、母马分娩后配种妊娠率无显著差异(P>0.05),母马分娩后配种返情率显著降低(P<0.05)。与对照组相比,L-精氨酸组母马试验第21天血浆总一氧化氮合成酶(TNOS)、内皮型一氧化氮合成酶(eNOS)活性与一氧化氮(NO)含量无显著差异(P>0.05);试验第45天血浆TNOS活性显著降低(P<0.05),NO含量极显著降低(P<0.01),eNOS含量无显著差异(P>0.05)。与对照组相比,L-精氨酸组母马试验第21天血浆氨(NH_3)、尿素氮(UN)含量无显著差异(P>0.05);试验第45天血浆NH_3含量极显著降低(P<0.01),UN含量无显著差异(P>0.05)。与对照组相比,L-精氨酸组母马试验第21、45天血浆生长激素(GH)、胰岛素样生长因子-Ⅰ(IGF-Ⅰ)、胰岛素(INS)含量均无显著差异(P>0.05)。结果提示,伊犁马母马围产期补喂L-精氨酸可改变母马体循环血浆TNOS活性与NO、NH_3含量,同时降低母马分娩后配种返情率,但对新生马驹体重、体尺参数、分娩后配种妊娠率无显著影响。L-精氨酸可作为营养调控剂,用于母马的妊娠最后期营养补充或分娩后护理以改善母马的繁殖力。

The aim of this study was to investigate the effects of supplementary feeding L-arginine on blood parameters of Yili mares,growth of newborn foals,and mating pregnancy rate and re-service rate after childbirth during the last 21 days of pregnancy and 25 days after delivery.Thirty Yili mares with similar age,body weight,height at withers,and due date were selected for test and divided into 2 groups,control group(n=15)and L-arginine group(n=15).The mares in control group were fed a basal diet,and those in the L-arginine group were fed an experimental diet which supplemented with 0.5%L-arginine on the basis of the basal diet formula,and the supplementary feeding amount of L-alanine was 60 g/(horse·d).Newborn foal body weight and body size parameters were measured within 12 h on mares after childbirth,and pregnancy rate and re-service rate during mating were counted.Mare venous blood samples were collected on days 0(before the supplementary feeding trial),21,and 45 of trial.The results showed that compared with the control group,there were no significant differences in the body weight,body size parameters,and mating pregnancy rate of mares after delivery in the L-arginine group(P>0.05),and the mating re-service rate of mares after delivery in the L-arginine group was significantly decreased(P<0.05).Compared with the control group,there were no significant differences in the plasma total nitric oxide synthase(TNOS)and endothelial nitric oxide synthase(eNOS)activities and nitric oxide(NO)content on the day 21 of trial in the L-arginine group(P>0.05);the plasma TNOS activity was significantly reduced(P<0.05),the NO content was extremely significantly reduced(P<0.01),and the eNOS activity was not significantly changed on the day 45 of trial in the L-arginine group(P>0.05).Compared with the control group,there were no significant differences in ammonia(NH 3)and urea nitrogen(UN)contents on the day 21 of trial in the L-arginine group(P>0.05);the plasma NH 3 content was extremely significantly reduced(P<0.01),and there was no significant difference in the UN content on the day 45 of trial(P>0.05).Compared with the control group,there were no significant differences in the plasma growth hormone(GH),insulin-like growth factor-Ⅰ(IGF-Ⅰ),and insulin(INS)contents on the days 21 and 45 of trial in the L-arginine group(P>0.05).The results suggest that supplementary feeding L-arginine during peripartum of Yili mares can change the plasma TNOS activity,NO and NH 3 contents in the mares’body circulation,and reduce mating re-service rate after delivery of mares,but cannot significantly affect the body weight,body size parameters of newborn foals and the mating pregnancy rate after delivery of mares.L-arginine can be used as a nutritional regulator for nutritional supplement of mares during last trimester or the nursing after childbirth to improve fertility of mares.