人工养殖陆封型大西洋鲑的生物学特性

Biological characters of landlocked Atlantic salmon Salmo salar in artifcial culture

2000年3月从美国缅因州格兰特湖(GrantLake)引进陆封型大西洋鲑(Salmosalar)发眼卵,从孵出仔鱼开始,在人工养殖条件下,采用实验生态学方法,观察其形态特征、年龄、生长、食性、性腺发育、繁殖生态等生物学特性,研究其生长发育所需条件,分析养殖环境因子对其生长发育及繁殖生理的影响。结果表明,陆封型大西洋鲑3龄组体重(W)与叉长(L)相关方程为W=0.0131L2.9949;可完全投喂用人工颗粒饲料;在淡水中饲养3年(11783度日)性腺可发育成熟。统计980尾性成熟雌鱼的产卵率可达98%以上,成熟个体平均相对怀卵量为1885粒/kg体重。成熟雄性精子数量为200亿/mL,人工繁殖时雌雄比为2∶1,受精率75%～92%。

The eyed eggs of Atlantic salmon Salmo salar were introduced from the Grant Lake of America in March 2000. Two culture basements were used for the aquaculture. The water temperature in Bohai spot was 0-18 ℃ and in rural Beijing was 1.85-22.37 ℃. The culture period was three years. Three groups of data from the salmon were divided in fork length after three years culture in the two culture spots, which were 3 cm (1-year-old), 27.4 cm (2-year-old) and 43.3 cm (three-year-old). The results show that during three years of age the landlocked salmon followed the equation W=0.013 1L^(2.994 9)(r=0.893 3), where W referred to body weight and L fork length, and during two years of age the equation was W=0.013 6L^(2.939 4)(r=(0.893 4).) The landlocked salmon can be completely fed with artificial diets during the culture and the mature age in the fresh water culture is three years old (11 783 ℃·d) that in 980 individual female adults, the spawning rate was over 98% and the opposite fecundity of individual female was 1885 /kg body weight. The sperm density of mature male was 2×10^(11) /mL. The ratio of female to male was 2∶1 during the artificial fertilization and the fertilized rate was 75%-92%.