Effect Of Dietary Containing Various Oil Ratios In Formulated Diets On Growth, Body Composition And Digestive Enzymes Of Chinese Mitten Crab (Eriocheir Sinensis)

The Chinese mitten crab (Eriocheir sinensis) is an important aquaculture species inChina. It is widely distributed, a long history aquaculture and occupy a very importantrole in aquaculture in China. This study was conducted to determine the effect with thetotal amount of basis diets was added in different proportions of3%fish oil(FO):soybean oil(SO) instead of raw fish on growth, development, fatty acid composition,and digestive enzymes with the formulated diets substitution of trash of Chinese mittencrab. In order to provide a scientific basis on suitable fish oil, soybean oil ratio in theformulated diets of Chinese mitten crab. The formulation of basal diet offered by theShanghai Ocean University, and processed by Ba Tai Feed Co., Ltd. Nantong, Jiangsu.Add oil by artificial way after the spraying. Five formulated diets were containeddifferent proportions of fish oil, soybean oil with resulting the ratio were all FO(T1),FO:SO was2:1(T2), FO:SO was1:1(T3), FO:SO was1:2(T4), all SO(T5),and the trashfish group numbered T6. The larvae crab were purchased from Chongming County. Theculture tests were carried out in Fisheries Technology in the promotion of aquaculturebase station characteristics, Chongming County, Shanghai, it lasted231days, fromMarch20th to November5th. Random sampling three time according to the moltingand growth pattern at the July15, September25and November5th respectively，taken20male and female crabs randomly from each group. Then made record of weigh,carapace length and carapace width. Followed take the hepatopancreas, gonads, muscleby vivisection, and then determined the hepatopancreas index(HSI), gonad index(GSI)and the rate of muscle(%). And fresh hepatopancreas, gonads and muscle stored at-20℃for biochemical measurements. The main results are as follows, 1. The survivals of both male and female crab between six diets were no significantlydifference. The T5group of female crab gets a lowest per unit of product to other group.T5group of male crab gets a significantly lower per unit of product to T1, T2and T3.The T3group gets highest per unit of production in both male and female crabs. Eachexperimental group has a significantly influence on the growth and hepatopancreasindex (HSI) of Chinese mitten crab in the three sampling. The T5group of male crabweight gain was significantly lower than T2, T3and T6group at the last sample. Thedifferent diets has a significantly influence on the female crab hepatopancreas index atJuly15, the first sampling. The ovarian index of group T5was significantly higher thanin T1group. There were significant impacts of different diets on moisture, total fat,crude protein content in hepatopancreas and muscle, moisture, total fat in ovary of thefemale crab at the last sampling. There were significant impacts of different diets onmoisture, total fat content in hepatopancreas and muscle, total fat, crude protein in testisof the male crab. In conclusion, it not only has some influence on the growth,development hepatopancreas index, gonad index and the ratio of muscle of Chinesemitten crab, but also has significantly influence on composition of hepatopancreas,gonad and muscle.The results indicated that the diets add fish oil, soybean oil ratio of1:1can achieve better farming effects and nutritional value.2. The results indicated the major fatty acids of C16:0, C18:0, C16:1n-7, C18:1n-7,C18:1n-9, linoleic acid(LOA), linolenic acid(LNA), arachidonic acid(ARA),eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA) have no significantlydifference in six diets in the female crab hepatopancreas.The six diets has significantlyinfluence of the major fatty acids of C16:0, C16:1n-7, C18:1n-9, LOA, LNA, ARA,DHA of male crab hepatopancreas. C16:0、ARA and SFA content decreased with theincrease in the proportion of soybean oil in the formulated diets. LOA, LNA, PUFA,n-6/n-3PUFA increased with the increase in the proportion of soybean oil in theformulated diets. It has significantly influence of C16:0、C18:1n-9、C18:1n-7、C18:2n-6、ARA、DHA、SFA、PUFA、HUFA in female ovary of six diets. The results indicted that C18:1n-9increased with the increase in the proportion of soybean oil inthe formulated diets except T1. The six diets has significantly influence of LOA、ARA、EPA、DHA、SFA、PUFA、HUFA in testis in male. There are significantly influence ofC16:0、C18:1n-9、C18:1n-7、ARA、SFA、HUFA in muscle of female and C16:0、C18:0、C16:1n-7、C18:1n-7、C18:2n-6、ARA、DHA in muscle of male. In conclusion,there were no significantly on the EPA and DHA in hepatopancreas of T2, T3and trashfish group, but they higher than other group. The EPA and DHA in ovary of female weresignificantly influenced by diet except T1. But the major fatty acid in testis of male hasno significantly influenced by diet. The ARA and EPA in muscle of male are consistentin the trend of the experimental diet group. The EPA and DHA in muscle of female andEPA in muscle of male were effect by diet but there were no significantly different.3. The results indicted that there was no significant difference of tryptase activity in thehepatopancreas and intestine of Chinese mitten crab. Tryptase activity in stomach of theformulated diet group was significantly higher than the trash fish group. Tryptaseactivity in stomach was significantly higher than in the hepatopancreas and intestine ofthe formulated diet group.The pepsin vitality of various parts of the Chinese mitten crabhas no significantly influence of the two diets.The lipase in intestine of formulated dietwas significant higher than trash fish group in Chinese mitten crab. The lipase activityin three parts in descending order of the intestine, stomach and liverhepatopancreas.The amylase vitality in intestine of trash fish group was significanthigher than formulated diet. The amylase vitality in formulated diet is highest instomach, but the trash fish group has the highest amylase vitality in intestine.