长江老江河国家级四大家鱼原种场鲢的生长特征

Growth Character of Silver Carp at National Original Breeding Farm in Lake Laojianghe,Middle Reaches of the Yangtze River

鲢(Hypophthalmichthys molitrix)是我国传统食用鱼,也是国际上养殖产量最高的鱼种。长江是鲢生产的摇篮和优质基因库。本文分析了2008年1月及12月采自湖北监利县老江河国家级四大家鱼原种场151尾鲢样本的年龄和生长特征,结果显示,体长(L)与鳞长(R)呈直线关系L=205.96R-6.374 0(r=0.948 6),体重(W)与体长呈幂函数关系W=0.023 4L2.941 1(r=0.995 5),生长规律可用Von Bertalanffy方程Lt=93.77[1-e-0.208 7(t-0.031 1)]和Wt=19 293.35[1-e-0.208 7(t-0.031 1)]2.941 1表达。群体的生长拐点位于ti=5.14,拐点体长Lr=61.47 cm,拐点体重Wr=5 570.85 g。分析表明,渐近体长、渐近体重及拐点年龄等参数,老江河鲢的比20世纪80年代中期天鹅洲和90年代初湖口地区鲢的要低,生长参数发生了一些变化。

Silver Carp （Hypophthalmichthys molitrix） is a traditional edible fish in China with the highest yield cultured. Yangtze River is served as an excellent resource for fish production and gene pool conservation of silver carp. This paper analyzed the age and growth characters from 151 silver carp samples collected from January 2008 and December at the National Original Breeding Farm （NOBF） located in Jianli County, Hubei Province （29°35＇N, 113° 00＇E） in which the four major Chinese Carps are cultured. The result indicated that the linear relation between body length （L） and scale length （R） was L = 205.96R - 6.374 0 （ n = 151, r = 0.948 6） and the function relationship between body length and body weight （W） was W = 0.023 4L^2.9411 （ n = 151, r = 0.995 5）. Moreover, the growth model could be described by Van Bertalanffy equation as Lt = 93.77[1 - e^-0.2087（t-0.0311） ] and Wt = 19 293.35[1 - e^-0.2087（t-0.0311）]^2.9411. The growth inflexion was ti = 5.14 years as the inflexion point of body length and body weight was Lr = 61.47 cm and Wr = 5 570.85 g, respectively. The value of growth parameters we got in this study, such as progressive body length, progressive body weight and age of inflecting point, have become smaller compared with the silver carp sampled in the Tian-e-zhou National Reserve in the middle of 1980s and Hukou area in 1990s.