三疣梭子蟹(Portunus trituberculatus)幼蟹饲料中胆固醇的适宜添加量研究

采用单因素实验设计方法, 以初始体重为20g左右的三疣梭子蟹(Portunus trituberculatus)幼蟹为实验对象, 胆固醇添加量为0.003%、0.3339%、0.655%、0.986%、1.303%和1.628%的实验饲料投喂8周, 研究其胆固醇需求量。结果表明, 饲料中添加0.003%—1.628%胆固醇对各处理组的存 活率无显著性影响(P>0.05)。随饲料胆固醇水平的上升, 三疣梭子蟹幼蟹的增重率呈先上升后下降的趋势, 当饲料胆固醇水平≥0.655%时, 三疣梭子蟹幼蟹的增重率呈下降趋势。折线模型表明, 饲料中胆固醇添加量为0.6%时, 三疣梭子蟹幼蟹的增重率、性腺指数和壳宽增加达到最高值。根据增重率折线模型结果, 作者认为三疣梭子蟹幼蟹饲料中添加0.6%左右胆固醇较为适宜

NEEDS OF DIETARY CHOLESTEROL FOR JUVENILE SWIMMING CRAB PORTUNUS TRITUBERCULATUS

To investigate cholesterol requirement by juvenile swimming crab Portunus trituberculatus, six diet groups were set up in one-way analysis model for adding 0.003%, 0.3339%, 0.655%, 0.986%, 1.303%, and 1.628% cholesterol into diet, respectively. Swimming crabs in initial weight about 20g were fed for 8 weeks. Results show that at the end of the experiment, the survival rate was not affected significantly by cholesterol enrichment in all six groups. Weight gain responded linearly to dietary cholesterol supplement up to 0.655% and then went down. Broken-line analysis indicated that dietary cholesterol of 0.6% satisfied the growth performance. At dietary cholesterol supplement 0.655%, crab had the highest weight gain, gland sex index, and carapace width gain. Therefore, we believe that, the optimal dietary cholesterol requirement by juvenile swimming crab was approximately 0.6%.