左旋肌肽对中华田园犬生长和健康的影响

Effects of L -Carnosine on Growth and Healthy of Canis lupus familiaris

本研究旨在探究外源添加左旋肌肽对中华田园犬生长性能、血清生化指标及抗氧化能力的影响。试验选取3月龄左右的健康中华田园犬24只,随机分为4组,每组6只,单圈饲养,1只为1个重复。对照组(C组)饲喂基础饲粮,试验组在基础饲粮中分别添加300(Ⅰ组)、600(Ⅱ组)和900 mg/kg(Ⅲ组)左旋肌肽。预试期为7 d,正试期为28 d。试验开始每周进行感官评价并测定生长性能,在试验第24天进行连续5 d的消化代谢试验,试验第28天采集5 mL左右血清样本,用于测定血清生化指标、免疫功能和抗氧化能力相关指标,最后进行D-木糖吸收试验,用于测定肠道吸收功能。结果表明:1)中华田园犬平均日增重(ADG)和平均日采食量(ADFI)都与左旋肌肽添加量成反比;随着左旋肌肽添加量的增加,犬感官评分值逐渐升高,Ⅲ组的评分值显著高于其他组(P<0.05)。2)犬的粪便评分值,Ⅱ组的平均得分最接近于最佳的粪便评分;随左旋肌肽添加量的增加,机体对粗脂肪的表观消化率升高;Ⅱ组和Ⅲ组粗蛋白质和粗纤维表观消化率显著高于C组(P<0.05)。3)各试验组血清胆固醇(CHO)含量均显著低于C组(P<0.05);Ⅰ组的血清谷草转氨酶(AST)活性显著高于C组(P<0.05);Ⅱ组血清免疫球蛋白A(IgA)、免疫球蛋白G(IgG)含量显著高于C组和Ⅰ组(P<0.05);Ⅲ组血清丙二醛(MDA)含量显著低于C组(P<0.05),Ⅲ组血清肌酐(CRE)含量显著低于C组(P<0.05),血清总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GSH-Px)和超氧化物歧化酶(SOD)活性均显著高于C组(P<0.05)。综上可知,饲粮中添加左旋肌肽可以提高中华田园犬感官评分,增强消化吸收功能,降低血清CHO的含量,提高免疫力和抗氧化能力;饲粮中左旋肌肽添加量以600 mg/kg为最佳。

This experiment was conducted to investigate the effects of L-carnosine on growth performance,serum biochemical indexes and antioxidant capacity of Canis lupus familiaris.Twenty-four 3-month-old Canis lupus familiaris were randomly divided into 4 groups with 6 dogs per group.The dogs in control group(group C)was fed a basic diet,and those in the groupsⅠ,ⅡandⅢwere fed the basic diet with 300,600 and 900 mg/kg L-carnosine,respectively.The preliminary test lasted for 7 d and the formal test lasted for 28 d.At the end of the experiment,sensory evaluation was performed and indicators related to growth performance,serum biochemical indexes,immunologic function and antioxidant capacity were measured.The results showed as follows:1)the average daily gain and average daily feed intake of dogs were inversely proportional to the additive amount of L-carnosine.With the increase of L-carnosine additive amount,the sensory scores of dogs increased gradually,and the scores in groupⅢwere significantly higher than those in other groups(P<0.05).2)For the fecal score,mean scores in groupⅡmost closely matched the optimal fecal score;with the increase of L-carnosine additive amount,the apparent digestibility of crude fat was increased,the apparent digestibilities of crude protein and crude fiber in groupsⅡandⅢwere significantly higher than those in group C(P<0.05).3)Serum cholesterol(CHO)content in experimental groups was significantly lower than that in group C(P<0.05);the activity of glutamic-oxalacetic transaminase(AST)in serum in groupⅠwas significantly higher than that in group C(P<0.05);the contents of immunoglobulin A(IgA)and immunoglobulin G(IgG)in serum in groupⅡwere significantly higher than those in groups C andⅠ(P<0.05);the content of malondialdehyde(MDA)in serum in groupⅢwas significantly lower than that in group C(P<0.05),and the content of serum creatinine(CRE)in groupⅢwas significantly lower than that in group C(P<0.05).However,the total antioxidant capacity(T-AOC),the activities of glutathione peroxidase(GSH-Px)and superoxide dismutase(SOD)in serum were significantly higher than those in group C(P<0.05).In summary,dietary L-carnosine can improve the sensory score of canine,increase digestion,absorption and metabolism ability,reduce the content of total cholesterol in serum,improve the body immunity and antioxidant capacity;dietary suitable L-carnosine supplemental level is 600 mg/kg.