饲粮半胱氨酸水平对离乳期梅花鹿瘤胃发酵参数和氨基酸代谢的影响

Effects of Dietary Cysteine Levels on Rumen Fermentation and Amino Acid Metabolism of Sika Deer during Weaning Period

试验旨在研究饲粮半胱氨酸水平对离乳期梅花鹿瘤胃发酵参数和氨基酸代谢的影响。采用单因素试验设计,将16只3月龄雄性梅花鹿仔鹿分为4组(每组4个重复,每个重复1只),组间体重差异不显著(P>0.05)。对照组(Ⅰ组)饲喂半胱氨酸水平为2.8 g/kg的基础饲粮,试验组分别饲喂半胱氨酸水平为4.8 g/kg(Ⅱ组,基础饲粮+2.0 g/kg半胱氨酸)、6.8 g/kg(Ⅲ组,基础饲粮+4.0 g/kg半胱氨酸)和10.8 g/kg(Ⅳ组,基础饲粮+8.0 g/kg半胱氨酸)的试验饲粮。试验预试期15 d,正试期30 d。结果表明,与Ⅰ组相比:(1)Ⅱ组异丁酸、异戊酸和戊酸浓度显著提高(P<0.05);(2)Ⅱ组瘤胃游离蛋氨酸、丝氨酸、赖氨酸、组氨酸和鸟氨酸浓度显著降低(P<0.05);(3)Ⅳ组半胱氨酸的表观消化率显著提高(P<0.05);(4)Ⅱ组血清游离天冬氨酸、氮和羟赖氨酸浓度显著降低(P<0.05)。综上,在本试验条件下,饲粮半胱氨酸水平为4.8 g/kg时有利于梅花鹿仔鹿瘤胃发酵、降低瘤胃和血清中游离氨基酸浓度。

This experiment investigated the effects of dietary cysteine(Cys)levels on the rumen fermentation parameters and amino acid metabolism of sika deer during weaning period.A single factor of trial was designed.16 healthy sika deers aged of three months were divided into four groups with four replicates per group and one per replicate.There was no significant difference in body weight between groups(P>0.05).The control group(groupⅠ)was fed basal diet with Cys levels of 2.8 g/kg,and the experimental groups were fed experimental diets with Cys levels of 4.8(groupⅡ,basic diet+2.0 g/kg Cys),6.8(GroupⅢ,basic diet+4.0 g/kg Cys)and 10.8 g/kg(GroupⅣ,basic diet+8.0 g/kg Cys)respectively.The pre-trial period lasted for 15 days,and the trial period lasted for 30 days.The results showed as follows:compared to the groupⅠ,(1)dietary Cys significantly increased the content of isobutyric acid,valeric acid and isovaleric acid of groupⅡ(P<0.05).(2)Dietary Cys significantly reduced the content of free methionine,serine,lysine,histidine and ornithine in rumen fluid of groupⅡ(P<0.05).(3)Dietary Cys significantly increased the apparent digestibility of Cys of groupⅣ(P<0.05).(4)Dietary Cys significantly reduced the content of serum free aspartic acid,ammonia and hydroxylysine of groupⅡ(P<0.05).In summary,under the conditions of this experiment,dietary Cys levels was 4.8 g/kg that is beneficial to the rumen fermentation,reduces the rumen free amino acids and serum free amino acids of sika deer during weaning period.