Exploration Of The Key Points In The Pond Farming Process Of Chinese Mitten Crab(Eriocheir Sinensis)

The Chinese mitten crab (Eriocheir sinensis), also known as crab, is importantfreshwater aquaculture species. By setting different stocking densities, specifications,diet. Crab growth performance study of different specifications, different densities ofcrab physiological adaptation, the impact of different diets on body composition, toprovide guidance for the breeding and rearing of the Chinese mitten crab after holdingculture.Phase I: Research different stocking size and density on the of crab growthperformance and physiological adaptation. Test time from March2011to November,breeding time of240days, on the Aquaculture Technology Extension Station ofChongming County, Shanghai. Breeding experiments of this stage of the test is dividedinto different stocking densities and different stocking size breeding trials. Thedifferent specifications breeding test group is divided into three specifications that issmall size (3-4g), middle size (6-7g) and large-sized group (10-12g), in May, July andSeptember, three specifications group crab complete a molting female and male crab30each for the growth of data analysis.Use15female,15male crabs measuring basicgrowth parameters and content of edible parts of the crab harvesting from the group ofthe specifications. Harvesting in mid-November, all the harvesting statistics totaloutput, the survival rate and specifications group of female and male crab in thenumber of different specifications intervals. Different density of breeding test isdivided into three groups of density that is low-density group (500/acre), mediumdensity (1,000/acre) and high density group (1500/acre), experimental the end ofeach experimental group were randomly sampled nine, taking blood, muscle andhepatopancreas stored at-80℃refrigerator Determination for the indicators.30samples from each group were weighed, take the muscle, gonad and hepatopancreasfor each growth index determination.Phase II: Research the impact of different diets and specifications of the crab bodycomposition. The time from March2010to November,breeding time of240days, onthe Aquaculture Technology Extension Station of Chongming County,based by thelaboratory for processing, and take the artificial spray add3%of oils and fats (fish oil:soybean oil=1:1). The test is divided into two groups, namely the group of trash fishand compound feed group. November6, sample collection, samples collected last complete reproductive molting, the basic mature female gonad development male crab.The two diet breeding female and male crabs taken from each of three parallelbreeding groups, each pool of three kinds of specifications, the male and female crabs10of each measuring weight, shell length, shell width, and dissected hepatopancreas,gonads, muscle and other tissue hepatosomatic index (HIS), gonad index (GSI) and themeat rate (%). From two diet groups female and male each select six crab anatomyhepatopancreas, gonads and muscle stored at-20℃used for body compositionanalysis. The obtained results are as follows:1. Stocking size does have a certain influence on the early growth of the Chinesemitten crab, the performance of the proportional relationship between the weight andstocking size higher than the female and the male crab crab, but to stocking size ofbreeding late survival rate of crabIncubation specifications and yield caused nosignificant difference. The specifications distribution, and female in each experimentalgroup, the specifications of the crab distribution are in line with the normal distribution,the male crab size160-180g majority of female crabs100-120g majority. The femalecrab stocking small size male crab easier to raise a larger market size crab stockinglarge size is easier to keep out the larger market size of female crabs.2. Stocking density of Chinese mitten crab, the growth of a significant impact,performance bred specifications of the low-density group was significantly higher thanthe high density group the hepatopancreas index of the high-density group wassignificantly higher than the other test groups. Physiological adaptability, serum lacticacid content of high density group was significantly higher than the other test groups,the cholesterol content of low-density group was significantly higher than that in thehigh-density group. Muscle glycogen content increased with increasing stockingdensity, the glycogen content in the liver pancreas contrary trend.3. Fed different diets and different incubation specifications the Chinese mitten femalecrab edible part of the content of the difference was not significant; There are somedifferences between the different specifications of the same bait and same Incubationspecifications of different food groups nutrients content. Specifications and bait agreater impact on the the conventional nutritional content of the ovaries of female crabs is not proportional to the relationship between the nutritional value of thecommodity female crabs and specifications. Chinese mitten crab fed different diets anddifferent incubation specifications edible part of the content; There are somedifferences between the different specifications of the same bait and same incubationspecifications of different food groups nutrients and lipid composition of content.