低蛋白质日粮补充赖氨酸、蛋氨酸对离乳期梅花鹿氮代谢的影响

为研究低蛋白质日粮添加赖氨酸和蛋氨酸对仔鹿氮代谢的影响,采用4×4完全拉丁方试验,选取3月龄、健康、离乳梅花鹿仔鹿4只,体重为(30±0.12)kg(X?±SD),进行消化代谢试验。对照组(Ⅰ组)饲喂16.28%粗蛋白质的高蛋白质日粮,试验组饲喂13.40%粗蛋白质,添加0.23%赖氨酸,并分别添加0(Ⅱ组)、0.06%(Ⅲ组)、0.12%(Ⅳ组)蛋氨酸的低蛋白质日粮。结果表明:1)对照组蛋白质消化率显著高于Ⅱ组(P<0.01)、Ⅲ组和Ⅳ组(P<0.05),脂肪消化率显著低于Ⅱ组(P<0.01),其他营养物质消化率差异不显著(P>0.05)。2)对照组和Ⅳ组蛋氨酸消化率显著高于Ⅱ组和Ⅲ组(P<0.05),对照组其余氨基酸消化率(赖氨酸、胱氨酸除外)显著高于各试验组(P<0.05)。3)对照组吸收氮显著高于Ⅱ组(P<0.01)、Ⅲ组和Ⅳ组(P<0.05),尿氮排放量显著高于各试验组(P<0.05),氮利用率及氮生物学效价低于各试验组(P>0.05)。4)对照组尿嘌呤衍生物总排放量显著大于Ⅱ组(P<0.01)和Ⅲ组(P<0.05),尿囊素显著大于Ⅱ组(P<0.01)、Ⅲ组和Ⅳ组(P<0.05),对照组、Ⅲ组和Ⅳ组黄嘌呤和次黄嘌呤显著高于Ⅱ组(P<0.01)。补充赖氨酸、蛋氨酸可改善低蛋白质日粮仔鹿营养物质消化率利用率,除粗蛋白外其他营养物质消化率与常规蛋白质水平相近,甚至更好,提高氮沉积、氮利用率和生物学效价,改善氮平衡,减少氮排放,降低环境污染。

Nitrogen metabolism in sika deer on a low protein diet supplemented with lysine and methionine

The effect of a low crude protein (CP) diet supplemented with amino acids on nitrogen metabolism in four three month old sika deer fawns mean live weight (30±0.12) kg] was investigated using a 4×4 Latin square design experiment. Four diets were compared; control (groupⅠ) fed a 16.28% crude protein diet, a group fed 13.40 % CP diet supplemented with 0.23% lysine and 0 (group Ⅱ), 0.06% (group Ⅲ), 0.12% (group Ⅳ) methionine. The results show that the CP digestibility of the control group was significantly greater than group Ⅱ (P<0.01), Ⅲ and Ⅳ (P<0.05) but ether extract digestibility was lower than group Ⅱ (P<0.01). No treatment differences for other nutrients were found (P>0.05). Methionine digestibility in the control group and group Ⅳ was significantly greater than group Ⅱ and group Ⅲ (P<0.05); digestibility of other amino acids (except lysine and cystine) in the control group was significantly greater than all other groups (P<0.05). Nitrogen (N) absorption in the control group was significantly greater than group Ⅱ (P<0.01), Ⅲ and Ⅳ (P<0.05) while urine N emissions were significantly greater and N utilization lower than other groups (P<0.05). Total urine purine emissions in the control group were significantly greater than group Ⅱ (P<0.01) and Ⅲ (P<0.05) and allantoin emissions significantly greater than group Ⅱ (P<0.01), Ⅲ and Ⅳ (P<0.05). Xanthine and hypoxanthine emissions in group Ⅱ was significantly lower than the control group (P<0.01), groups Ⅲ and Ⅳ (P<0.05). Supplementing with lysine and methionine improved the apparent digestibility of a low CP diet, approaching the digestibility of diets with a normal protein content and improving N retention and N utilization, reducing N emissions and helping to protect the environment.