| This research as experiments the materials take the An Kang native loach, through 4 relatively independent experiments, has conducted the research to the loach artificial propagation key technologies link, provides the basic research material take the time as the establishment loach artificial propagation technology system.1. The effect of hormone injection time water pH and water temperature on on inducted spawning in loach.The three hundred and sixty female parent fish were randomly divided into three groups: group I, 108 female parent fish were selected by hormone injection time; groupⅡ, 144 female parent fish were selected by water pH; groupⅢ, 108 female parent fish were selected by water temperature. The aim was to define the best hormone injection time, pH and temperature of water for the followed tests. The results showed that: (1)The best hormone injection time is 16:00~18:00. (2) The best water pH is 7.0~7.5. (3) The best water temperature is 24 ~ 26℃.2. The effect of different injection dose of hCG, LHRH-A2 and complex hormones hCG + LHRH-A2, DOM + LHRH-A2 on the spawning effect of loach.486 choosed female parent fish were assigend into 27 groups, each group of 18 loaches and each treatment consists of 3 replicates with 6 loaches each it were carried out on the basis of experiment 1. the results show that: (1) The optimum injection dose of hCG for spawning effect of loach was 30IU/g. (2) The optimum injection dose of LHRH-A2 for spawning effect of loach was 12μg/tail (3) The optimum injection dose of complex hormones hCG+LHRH-A2 for spawning effect of loach was 18IU/g+ 10μg/tail (4) The optimum injection dose of complex hormones DOM+LHRH-A2 for spawning effect of loach was 4mg/tail+4μg/tail. (5) After considered synthetically about resistance and price factors comprehensive consideration, we recommend the injection dose of 4mg DOM /tail+3μg LHRH-A2/tail.3. The embryonic development and hatching of An Kang native loach.After induction, loach fertilized eggs 6000 divide into 2 groups stochastically, each group of 3000, carried under the water temperature 24~26℃, pH 7.0~7.5 conditions gasifies the micro running water hatching, uses in the embryonic development rule observation and the hatching effect statistical analysis separately. The results showed that (1) In the above conditions, the loach eggs had normal development, An Kang wild loach embryo formation can be divided into blastodisc formation stage, cleavage stage, gastrulatio stage, neurulation stages, sarcomere formation occurs and the follicle stage, the stage of organ formation and the membrane phase of a total of 7 stages 27 developmental periods. (2) From fertilization to its incubation period was 30h45min±15min; hatching rate was 91.27%, malformation rate was 4.38%.4. Study on two kinds of loach hatch method was effected on.We divided 25144 eggs into two groups randomly which used artificial spawning. The first group was 13784 eggs that divided into five repeats and use hydrostatic with fish eggs hatching nest attached to hatch, the second group includes 11330 eggs which used water to the nest to hatch hatching. The incubation period and hatchability of two incubation methods were 38.56h±1.04,88.97%±0.78 and 30.52h±0.89,92.25%±0.84. These results indicated that hatching without nest in running water is better than hatching with nest in standing water under such incubation period and hatchability conditions.
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