Effects Of Compound Additives On Growth Performance,Serum Biochemistry,Rumen Fermentation And Apparent Nutrient Digestibility Of Sheep In Cold Season

The purpose of this experiment was to study the effects of compound additives on the growth performance,serum biochemistry,rumen fermentation and apparent nutrient digestibility of sheep in cold season,so as to provide data reference for improving the growth performance and disease resistance of sheep in cold season.Sixty 6-month-old male Altay sheep with similar body weight[（39.64±2.72）kg]and good health were randomly divided into 4 groups with 15 sheep in each group.The control group was fed with basic diet,and the compound additive group 1（E₁group）was added with 2.2%compound additive I（seabuckthorn leaf powder:ammonium chloride:glutamine=15:5:2）,and the compound additive group 2（E₂group）was added with 2.2%compound additive II（seabuckthorn leaf powder:ammonium chloride:guanidine acetic acid=15:5:1）,Compound additive group 3（E₃group）added2.2%compound additive III（seabuckthorn leaf powder:ammonium chloride:glutamine:guanidine acetic acid=15:5:2:1）to the basic diet.The pre-trial period is 15 days and the pilot period is 30 days.The results show that:（1）In the whole experimental stage,the average daily feed intake of E₁,E₂and E₃group was significantly or very significantly higher than that of the control group（P<0.05 or P<0.01）;The feed weight ratio of E₁and E₃group from day 1 to 15 was significantly lower than that of the control group（P<0.01）.（2）The contents of serum total protein（TP）,globulin（GLB）,immunoglobulin M（Ig M）and immunoglobulin A（Ig A）in E₃group were significantly or very significantly higher than those in the control group（P<0.05 or P<0.01）.The content of serum interleukin-2（IL-2）in E₁group,E₂group and E₃group was significantly lower than that in the control group（P<0.01）.The contents of serum ACTH,cortisol,insulin,triiodothyronine and thyroxine in E₂and E₃groups were significantly or very significantly lower than those in the control group（P<0.05 or P<0.01）.The serum total antioxidant capacity（T-AOC）and superoxide dismutase（SOD）activity in E₂and E₃groups were significantly higher than those in the control group（P<0.01）,and the content of serum malondialdehyde（MDA）was significantly lower than that in the control group（P<0.01）.（3）The concentrations of total volatile fatty acids,acetic acid and ammonia nitrogen in rumen juice in E₂and E₃groups were higher than those in the control group（P>0.05）.The concentration of isovaleric acid in rumen fluid of E₂group was the highest,which was significantly higher than that of the control group（P<0.05）,and there was no significant difference with E₁group and E₃group.The acetic acid/propionic acid in rumen juice of E₁group was the highest,which was significantly higher than that of each treatment group（P<0.05）,the total volatile fatty acids,propionic acid and butyric acid were lower than those of the control group（P>0.05）,and the concentration of ammonia nitrogen was lower than those of the control group,E₂and E₃groups（P>0.05）.（4）The apparent digestibility of dry matter,organic matter,crude protein,neutral detergent fiber,acid detergent fiber and total energy in E₁group was the highest,which was significantly higher than that in the control group（P<0.01）,and the apparent digestibility of crude fat in E₂group was the highest,which was significantly higher than that in the control group（P<0.01）.It can be seen that the addition of compound additives in the diet can promote the growth and development of sheep in cold season,enhance the immune function,enhance the antioxidant capacity and improve the digestibility of nutrients.The comprehensive test results showed that the practical application effect of compound additive I（seabuckthorn leaf powder:ammonium chloride:glutamine=15:5:2）in sheep production in cold season was better based on the average daily gain and apparent digestibility of nutrients.