野生鲇性腺发育及其与肝重指数关系的研究

珠江流域雌性鲇鱼的GSI在 3月份形成峰值 ,10月份达到低谷 ;辽河流域雌性鲇鱼的GSI在 5月份出现一个峰值 ,9月份达到谷底。两个流域雄鱼的GSI周年波动不大 ,变化趋势与雌鱼相似。珠江流域雌性鲇鱼的HSI在 1月份和 10月份保持较高水平 ,3～ 7月份水平较低 ;辽河流域雌性鲇鱼的HSI在 1～ 3月份保持较高水平 ,9月份最低。两个流域雄鱼的HSI季节变动趋势与雌鱼相似。两个流域野生鲇鱼GSI的周年变化与性腺发育和产卵密切相关 ,雌鱼HSI的季节变化与肝脏的营养水平和物质代谢有关 ,与生殖活动有关联 。

野生鲇(Silurus asotus Linnaeus)资源开发与养殖

本文总结了近10年来国内外关于鲇鱼(Silurus asotus)养殖的基础和应用技术研究的最新进展:生物学、育种、内分泌生理及其调控、人工繁殖技术、苗种培育和成鱼饲养。结果表明:该种鲇鱼具有很高的经济价值和人工养殖前景,已经成为日本和中国内陆水域新的养殖对象。解决苗种的规模化生产和成鱼饲养的产业化问题是目前的当务之急。

Seasonal Variations in Serological Profiles and Growth Status of Farmed and Wild Clarias gariepinus （Burchell, 1822） Obtained from Asaba, Nigeria

Seasonal variations in serological profiles and growth status of farmed and wild Clarias gariepinus were investigated. Serological profiles of Clarias gariepinus can be an effective tool for proper monitoring of stress induced by management practices in intensive fish culture, which may elicit devastating effect on fish. Spectrophotometry procedures were used to analyze serum parameters of Clarias gariepinus. No different seasonal patterns were observed for mean values of albumin, total protein, urea, cholesterol, glucose and alanine amino-transferase. However, aspartate amino-transferase showed different seasonal pattern. Levels of cholesterol and alanine amino-transferase were highly significant in farmed and wild fish, separately. Juvenile fish had high level of urea irrespective of season. Seasonal variations in water quality parameters were observed except for pH which had no seasonal pattern. The growth exponential shows b-values between -0.048 and 7.434 for Clarias gariepinus. Adult female and juvenile fish from the wild had the highest b-value and the least b-value, separately. In this study, b-values were higher in the wild fish than the farmed fish. The condition factor for Clarias gariepinus ranged from 0.422 to 0.698, and was observed to be high in juvenile fish. With a condition factor less than 1, fish may not be doing well, probably due to environmental stress. Some serological parameters varied according to season and environment of fish. Thus, serological profile of fish is an effective and sensitive tool to monitor fish response to stress factors in the environment.

小浪底钓鱼有技巧

举世闻名的黄河小浪底水利枢纽工程库区，自1998年底建成蓄水以来，以水面宽阔、鱼类繁多、景色秀丽、交通方便和免收钓费等优越条件，吸引着周边成千上万的钓友频频光顾。大凡去小浪底钓鱼的人很少放空。少者几千克，多则十几千克、几十千克。多为褐色高背鲫鱼，还有野生鲇鱼，也有黄河鲤鱼。从小浪底水库钓上来的鱼肉质细嫩、味道鲜美，食之很是惬意。