松针多糖对肉兔生长性能、营养表观消化率和免疫性能的影响OA

This experiment aimed to investigate the effects of pine needle polysaccharide(PNP)on the growth performance,apparent digestibility of nutrients,and immune function of meat rabbits.A single-factor random design was adopted.120 healthy and well-conditioned Iranian meat rabbits(35±2 days old)were selected and randomly divided into 4 groups:the control group and PNP test groups 1,2 and 3(with addition amounts of 0,0.03%,0.06%,and 0.12%respectively).The pre-trial phase lasted for 7 days,while the primary experimental phase spanned 35 days.The results showed that the final weight and average daily gain of the meat rabbits in test group 3 were significantly greater in comparison to those of the control group and test group 1(P<0.05).The feed-to-weight ratio of test group 3 was significantly lower than that of the control group and test group 1(P<0.05).The apparent digestibility corresponding to dry matter,crude protein as well as crude fiber content in meat rabbits of test groups 2 and 3 demonstrated a statistically significant increase relative to the control group(P<0.05),while the apparent digestibility level of crude fat in meat rabbits of test groups 2 and 3 was significantly higher than that of the control group(P<0.05).The thymus index and liver index of the meat rabbits in test group 2 were significantly higher than the corresponding values in the control group and test group 1(P<0.05),and the liver index of the meat rabbits in test group 3 was significantly higher than that in the control group and test group 1(P<0.05).The round sac index of the meat rabbits in test group 3 demonstrated a statistically significant increase relative to that of the control group and test group 2(P<0.05).The contents of immunoglobulin A and immunoglobulin G in the blood of meat rabbits in test groups 2 and 3 were significantly higher than those in the control group(P<0.05),and the content of immunoglobulin M in the blood of meat rabbits in test group 2 was significantly higher than that in the control group(P<0.05).In conclusion,adding PNP to the diet can significantly improve the growth performance,apparent digestibility of nutrients,and immune function of meat rabbits.Under the experimental conditions,the appropriate addition amount of PNP in the meat rabbit diet is 0.12%.