| This article reviews the advances of nutrition research for cultured Chinese soft-shelled turtle (Trionyx sinensis ) in the past ten years. The major aspects are about the character of ingestion and digestion, optimum requirements of protein and essential amino acids, suitable levels of lipid and essential fatty acids, carbohydrate, energy and rate of C/P, optimum requirements of inorganic elements, such as calcium, phosphorus and zinc. This report also makes mention of application of nutritional additives. Furthermore, the some experiments are conducted, such as protein requirement of turtle and digest-utilize, availability of amino acid in white fish meal and soybean meal for Trionyx Sinensis, change of digestive enzyme activities in intestinal canal of soft-shelled turtle fed bean cake, effect of feeding carnitine on growth and carcass trait of young shell-turtle, as well as investigate the effect of food ,living space and raised period on the nutrient component of Chinese soft -shelled turtle .Casein mixed into standard feeds as different ratio of protein, with 35%,40%,45% and 55%. Baby-turtles are fed by standard feeds with these different content of protein. After sixty days feeging, the growth rate of baby-turtle fed by the feed with 45% protein content is the highest among the treatment groups. While fish meal and bean cake were mixed as protein material into a kind of feed with 45% protein content, the feed with 59% fish meal / 5% bean cake or 55.5% fish meal/10% bean cake give the highest growth rate of baby-turtles. The result shows that baby-turtle had a lower ability of utilizing beak-cake protein when over-added.The apparent digestibility of protein and amino acids in white fish meal andsoybean meal for tronyx sinensis were determined by the indirect method using as a marker. The protein and amino acids digestibility of white fishmeal in fingerling turtle, young turtle and adult turtle were 84.90%, 92.12%, 92.94% and 85.29%, 91.91%, 92.61% respectively. The protein and amino acids digestibility of soybean meal in fingerling turtle, young turtle and adult turtle were 71.47%, 90.42%, 90.91% and 79.52%, 87.88%, 88.95% respectively. Digestibility of protein and amino acids in older turtle was higher than in young turtle . Also, it was found that amino acids of soybean meal could compensate each other with amino acid of white fish meal in turtle feed.Two groups of Chinese Soft-shelled turtle were bred by fed artificial diets added 15 percentage bean cake or not. Activities of several digestive enzymes from stomach and intestines were analyzed with the enzyme analytical method in different stages of domestication. The results showed that the activities of pepsin and tryptase changed along with the changes of animal protein /plant protein ratio. Under the same content of crude protein, the activity of tryptase in digestive tube fed bean cake decreased firstly, then went up gradually to normal degree. The activity of tryptase was higher than that of pepin. The activities of amylase and cellulase maintained a lower-level. An optimal level of fiber and starch can enlighten them slightly. No significant difference was observed in growth between two groups.An experiment was conducted to study the effect of feeding carnitine on growth and carcass trait of young shell-turtle. 160 turtles was allotted to 4 treatments (control and control +0.01%, +0.03%,+0.05% carnitine) set with two replicate pools per treatment in 30 1 for 60 days. Initial body weight of the turtle was from 40-48g. Significantly(P<0.05) higher the specific growth rate (SGR), acid-insoluble carnitine in muscle, free carnitine in livers were observed in turtle fed the died at 0.01%~0.05% carnitine added. Significantly (P<0.05) lower percentage of dissected fat of carcass,liver fat were same observed at them. The serum analysis indicated that carnitine supplement increase the GH and IGF-1 levels (P<0.05). All these provided that the feedsupplemented caraitine can effectively increase the long chain fatty acid- P -oxidati...
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