Browsing by Author "Nannan, Zhang"

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    Effects of dietary protein to energy ratio on growth, body composition and digestive enzyme activities in Eriocheir sinensis.
    (Wiley, 2016-04-16) Yanyan, Cui; Qianqian, Ma; Samwel Mchele Limbu; Zhenyu, Du; Nannan, Zhang; Erchao, Li; Liqiao, Chen
    This study aimed to determine the optimal protein to energy ratio (P/E ratio) and evaluate the effect of dietary protein and lipid levels on growth performance, body composition and digestive enzymes activities in Chinese mitten‐handed crab, Eriocheir sinensis. Nine practical diets containing three levels both for protein (DP 30%, 35% and 40%) and lipid (DL 2%, 7% and 12%) with P/E ratios ranging from 13.69 to 19.79 mg KJ−1 were fed to four replicates of crabs (3.39 ± 0.10 g) for 10 weeks. Weight gain increased significantly with the increase in DP level at each DL level. Moreover, weight gain increased in crabs fed with diets containing DL level from 2% to 12% and DP level from 30% to 35%. However, the diet containing 40% DP and 12% DL levels significantly decreased the growth performance and protein efficiency of the crabs. The whole crab and hepatopancreas lipid contents also increased as dietary lipid increased, but not dietary protein. The total protease activity increased significantly with the increase in dietary protein at each lipid level. The lipase activity was statistically comparable among different DL levels at each DP level. Taken together, the crab fed the diet containing 35% protein and 12% lipid levels with P/E 15.77 mg KJ−1 revealed optimal growth, feed utilization efficiency and digestive enzymes activities. Moreover, our study indicated that the higher dietary lipid level at a relatively lower dietary protein level could provide protein sparing effect in Eriocheir sinensis.
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    Soybean and cottonseed meals are good candidates for fish meal replacement in the diet for juvenile Macrobrachium nipponense. , 26(1): 309–324.
    (Springer, 2017-11-13) Yujuan, Huang; Nannan, Zhang; Wujiang, Fan; Yanyan, Cui; Samwel Mchele Limbu; Yunlong, Zhao; Fang, Qiao; Liqiao, Chen; Zhenyu, Du; Dong-Liang, Li
    Macrobrachium nipponense is a new aquaculture species with high market demand and is preferred as food by Asian consumers. However, its nutrient requirements and optimal dietary sources have not been fully evaluated. In the present study, we examined four common plant protein sources (soybean meal, cottonseed meal, rapeseed meal, and peanut meal) as partial replacement for 25% fishmeal protein in five isonitrogenous and isocaloric diets in M. nipponense for 8 weeks. The nutritional effects of the four plant protein sources were compared by means of growth performance, feed efficiency, histology, biochemical composition, oxidative stress, total hemocyte count, and in vitro digestion. Prawns fed the diets containing soybean (730.96 ± 33.50%) and cottonseed meals (672.32 ± 74.52%) had higher weight gain than those fed on rapeseed (503.71 ± 50.85%) and peanut (507.79 ± 52.10%) meal diets (p < 0.05). Similarly, the feed conversion ratios of prawns fed on soybean (1.66 ± 0.12%) and cottonseed (1.88 ± 0.06%) meal diets were significantly lower than those fed on rapeseed (2.37 ± 0.10%) and peanut (2.77 ± 0.16%) (p < 0.05) meal diets. No significant differences were found among groups in the hepatopancreas and intestinal histological characteristics, activities of antioxidant enzymes, and hemocyte number. The amino acid composition in diets and prawn muscles was comparable among groups. Soybean meal showed the highest in vitro digestibility. Taken together, soybean and cottonseed meals could be good candidates for partial fishmeal replacement in M. nipponense diets.