Effects of Different Dietary Whole Plant Forage Mulberry Addition Ratios on Growth Performance,Slaughter Performance,Meat Quality,Serum Antioxidant Indices and Nutrient Apparent Digestibility of Chuanbai Rex Rabbits
This experiment was conducted to investigate the effects of different dietary whole plant forage mul-berry addition ratios on growth performance,slaughter performance,meat quality,serum antioxidant indices and nutrient apparent digestibility of Chuanbai Rex rabbits,and to determine the appropriate addition ratio of forage mulberry as a non-conventional feed fiber source in the diet for Chuanbai Rex rabbits.A total of 150 Chuanbai Rex rabbits of 35-day-old with good health,similar body weight and similar genetic background(half male and half female)were randomly divided into 5 groups with 30 replicates per group and 1 rabbit per replicate.Rabbits in the control group were fed a basal diet,and those in the experimental groups were fed the basal diet supplemented with 6%,12%,18%and 24%forage mulberry,respectively.The pre-trial period las-ted for 7 days and the experimental period lasted for 32 days.The results showed as follows:1)different dieta-ry ratios of whole plant forage mulberry had no significant effects on the final body weight and average daily gain of Chuanbai Rex rabbits(P>0.05).Compared with the control group,the average daily feed intake in experimental groups was significantly decreased(P<0.05),but there was no significant difference among ex-perimental groups(P>0.05);the ratio of feed to gain in 6%and 24%addition groups was significantly de-creased(P<0.05).2)The eviscerated ratio and semi-eviscerated ratio of Chuanbai Rex rabbits showed a trend of decreasing first and then increasing with the increase of forage mulberry addition ratio.Compared with the control group,there were no significant differences in the eviscerated ratio and semi-eviscerated ratio in experi-mental groups(P>0.05),but the eviscerated ratio and semi-eviscerated ratio in 24%addition group were sig-nificantly higher than those in 18%addition group(P<0.05).Compared with the control group,the spleen in-dex in 12%addition group was significantly increased(P<0.05);the heart index in 12%addition group was significantly higher than that in 6%addition group(P<0.05).3)Different dietary ratios of whole plant forage mulberry had no significant effects on the drip loss ratio and cooked meat ratio in muscle of Chuanbai Rex rab-bits(P>0.05),but significantly increased the crude protein content in muscle(P<0.05),and significantly decreased the ether extract content in muscle(P<0.05).4)Compared with the control group,the serum total antioxidant capacity of Chuanbai Rex rabbits in 24%addition group was significantly increased(P<0.05),the serum catalase activity in experimental groups was significantly increased(P<0.05),and the serum total bile acid content in 12%,18%and 24%addition groups was significantly decreased(P<0.05).5)The apparent digestibility of each nutrient showed a trend of increasing first and then decreasing with the increase of forage mulberry addition ratio.Compared with the control group,the apparent digestibilities of dry matter,crude pro-tein,neutral detergent fiber,acid detergent fiber,ether extract and crude ash in 12%addition group were sig-nificantly increased(P<0.05).In conclusion,different dietary whole plant forage mulberry addition ratios have no adverse effects on growth performance and slaughter performance of Chuanbai Rex rabbits,but can in-crease the muscle crude protein content and decrease the muscle ether extract content;the antioxidant capacity and nutrient apparent digestibility of Chuanbai Rex rabbits can be improved by adding the appropriate ratio of whole plant forage mulberry in diet;under the experimental conditions,the appropriate ratio of whole plant for-age mulberry in diet for Chuanbai Rex rabbits is 12%.[Chinese Journal of Animal Nutrition,2024,36(11):7250-7261]