限制或过量添加脂溶性维生素对育肥阶段杜寒杂交肉羊屠宰性能、内脏器官发育和肉品质的影响

Effects of Restriction and Excess Amount of Fat-Soluble Vitamins on Slaughter Performance,Internal Organ Development and Meat Quality of Dorper×Thin-Tailed Han Crossbred Lambs during Fattening Stage

本试验通过研究饲粮中限制或过量添加脂溶性维生素(维生素A、维生素D、维生素E)对育肥阶段杜寒杂交肉羊屠宰性能、内脏器官发育和肉品质的影响,旨在评估NRC (2007)提出的脂溶性维生素推荐量是否适用于我国肉羊养殖。采用单因素试验设计,选择120只90日龄断奶后体重为(26.00±0.11) kg的杜寒杂交肉用绵羊,根据体重随机分为5组,每组12个重复,每个重复2只(公母各占1/2)。对照组(PC组)饲喂基础饲粮,按需要量提供维生素A、维生素D和维生素E复合制剂;试验组分别在PC组基础上扣除30%的维生素A(PC-VA组)、维生素D(PC-VD组)和维生素E(PC-VE组);另设过量添加组,其3种脂溶性维生素添加量均为对照组的7.5倍(PC-7.5组)。试验期100 d。结果表明:1) PV-7.5组的眼肌面积有高于PC组的趋势(P=0.06),各组肉羊的宰前活重(LWBS)、胴体重和屠宰率均差异不显著(P>0.05)。各组肉羊内脏器官重量及其占LWBS的比例均没有显著差异(P>0.05)。各组肉羊各胃室重量及其占复胃总重的比例均没有显著差异(P>0.05)。2) PC-7.5组的肉色亮度值显著低于除PC组外的其他各组(P<0.05); PC-VA组和PC-VE组的背最长肌C10∶0含量有低于PC组的趋势(P=0.07),PC-VA组和PC-VE组的背最长肌C20∶0含量有低于PC-7.5组的趋势(P=0.09);PC组的背最长肌半胱氨酸(Cys)含量显著低于其他各组(P<0.05),且PC组的背最长肌丝氨酸(Ser)含量显著低于PC-VA组和PC-7.5组(P<0.05)。结果提示,扣除30%或摄入过量的脂溶性维生素对杜寒杂交肉羊的屠宰性能和肌肉脂肪酸含量均无显著影响,但影响了肌肉氨基酸含量,从而对肉品质产生影响。

The purpose of this experiment was to investigate the effects of restriction and excess amount of fat-soluble vitamins(vitamin A,vitamin D and vitamin E)on slaughter performance,internal organ development and meat quality of Dorper×thin-tailed Han crossbred lambs during fattening stage,with an aim to evaluate if the recommendation of fat-soluble vitamins provided by NRC(2007)is suitable for the sheep production in China.A total of 120 Dorper×thin-tailed Han crossbred sheep(half male and half female)with average body weight of(26.00±0.11)kg after weaning at 90 days of age were used in the current study according to a single factor experimental design.All sheep were randomly divided into 5 groups according to their body weight with 12 replicates per group and 2 sheep per replicate(half male and half female).The control group(PC group)fed a basal diet which provided vitamin A,vitamin D and vitamin E compounds as required;30%of vitamin A(PC-VA group),vitamin D(PC-VD group)and vitamin E(PC-VE group)was deducted from PC group in the experimental groups,respectively;a high-dose group(PC-7.5 group)was set up which all fat-soluble vitamins were 7.5 times higher than that of the control group.The experiment lasted for 100 days.The results showed as follows:1)the eye muscle area of PV-7.5 group was tended to higher than that of PC group(P=0.06),there were no significant differences in live weight before slaughter(LWBS),carcass weight and dressing percentage of sheep among all groups(P>0.05).There were no significant differences in internal organ weights and their percentage of LWBS of sheep among all groups(P>0.05).There were no significant differences in each stomach weights and their percentage of total compound stomach weight of sheep among all groups(P>0.05).2)The meat color brightness value of PC-7.5 group was significantly lower than that of the other groups except the PC group(P<0.05);the Longissimus dorsi C10∶0 content of PC-VA group and PC-VE group was tended to lower than that of PC group(P=0.07),the Longissimus dorsi C20∶0 content of PC-VA group and PC-VE group was tended to lower than that of PC-7.5 group(P=0.09);the Longissimus dorsi cystine content of PC group was significantly lower than that of other groups(P<0.05),and the Longissimus dorsi serine content of PC group was significantly lower than that of PC-VA group and PC-7.5 group(P<0.05).The results suggeste that deduction of 30%or excess amount of fat-soluble vitamins intake have no significant impact on slaughter performance and muscle fatty acid content of Dorper×thin-tailed Han crossbred sheep,however,it affects the muscle amino acid content,which have potential impacts on meat quality.