水产养殖英语论文.docx

carp in captivity (A) foster mother （1）. Sexual maturity and sexual cycle of the Yangtze river basin (female general 2 age, male of 1 year of above the carp reach sexual maturity. Generally 3 ~ 5 month for the gonads mature and spawning period. After the first phase of the eggs Ⅵ ovarian to absorb degradation in July to the first Ⅱ period, then gradually development to enter the first Ⅳ period in November, and, on the winter period, the second year 3 ~ 4 months, meet appropriate environmental conditions, ovarian it quickly mature soon Ⅳ phase, the first to the first V period. The male sexual maturity (after the first JingChao degradation to reproduce Ⅲ period, 8 to 9 months into the first Ⅳ period, December to the first V period, and this period winter. Laying eggs in the different season all over south laying eggs for 2 ~ 3 month stage; The Yangtze river basin as a 3 ~ 4 month; The Yellow River is 4 ~ 5 month; The northeast region for 5 ~ 6 months. Spawning period sustainable 2 months or so commonly. （2）. The choice of mother and raising female carp should choose 2 years old, weight more than 1 kg, the male carp slightly small weight for about 0.5 kilograms. The choice should be body height, mother back thick, healthy body, strong, the figure is good, strong activity without injury. Source of good for breeding in the pond. Kiss fish pond area is general 1 to 3 mu, depth of water 1.5 meters or so, every year to clear a pond. Mother stocking density general 100-150 kg/mu, also can a few silver carps, it collection fish, to control the excessive breeding of plankton. After laying eggs in winter carp have to kiss before male and female fed separately, in order to avoid sudden high temperature when natural reproduction and sporadic carp spawn, usually can be male and female FenYang collection or a pond. Carp for bears are, appetite is big, raising the period shall be given enough food, also can be appropriately fertilization make water quality fertile, natural feed en