矛尾复虾虎鱼繁殖前营养组成的研究

2006年4月在辽宁省盘锦市大洼县三角洲附近海叉设拦网捕繁殖亲鱼矛尾复虾虎鱼Synechogobius hasta,对繁殖前该鱼的怀卵量、形态学指标及各组织的营养成分进行了测定.结果表明:(1)产卵前矛尾复虾虎鱼的卵径为(1150.41±186.64)μm,个体绝对怀卵量与体重、体长均呈直线相关关系.(2)雌性矛尾复虾虎鱼在性腺从Ⅲ期发育至Ⅳ期的过程中,鱼体的肥满度略有上升,肝体比、脏体比显著下降(P＜0.05),成熟系数显著增加(P＜0.05);鱼体蛋白质和脂类的含量均没有显著变化(P＞0.05);背部肌肉和性腺中蛋白质的含量显著增加(P＜0.05),但脂类含量增加不显著(P＞0.05);肝脏中蛋白质和脂类的变化不显著(P＞0.05).(3)矛尾复虾虎鱼在性腺发育至Ⅳ期时,雌鱼的肥满度和成熟系数均显著高于雄鱼(P＜0.05),而雌鱼和雄鱼的脏体比和肝体比均没有显著变化(P＞0.05);雌鱼体内蛋白质和脂肪的含量均显著高于雄鱼(P＜0.05),而雌鱼体内水分的含量却显著低于雄鱼(P＜0.05);雌鱼和雄鱼肌肉和肝脏内的蛋白质、脂肪和水分含量均没有显著性差异(P＞0.05).     

上海鱼类三新记录

2006年12月20日作者在金山区杭州湾城市沙滩水域采集到3种鱼类,经鉴定认为是上海地区新记录,保存于东海水产研究所环境研究室.现记述如下:     

Effect of dietary arachidonic acid levels on growth performance,hepatic fatty acid profile,intermediary metabolism and antioxidant responses for juvenile Synechogobius hasta

An 8‐week feeding experiment was conducted to determine the effect of dietary arachidonic acid (ARA) levels on growth performance, hepatic intermediary metabolism and antioxidant responses for juvenile Synechogobius hasta. Five isonitrogenous and isolipidic diets were formulated with arachidonic oil (containing 400 g ARA kg^?1) at inclusion levels of 0, 2, 4, 8 and 16 g kg^?1 to replace corn oil. Dietary ARA levels were 0.6, 8.6, 16.7, 32.7 and 64.8 g kg^?1 total fatty acids (FAs), respectively. Fish fed the 8.6–32.7 g ARA kg^?1 total FAs showed the highest weight gain, specific growth rate (SGR) and feed intake. By contrast, feed conversion ratio was the lowest for fish fed the 8.6–32.7 g ARA kg^?1 total FAs. Increasing ARA and total n‐6 fatty acid contents and declining linoleic acid content in liver were observed in fish fed the diet containing increasing dietary ARA levels. As a consequence, ∑n‐6/∑n‐3 ratios increased with increasing dietary ARA levels. Dietary ARA levels significantly influenced several enzymatic activities involved in hepatic intermediary metabolism, such as succinate dehydrogenase, lactate dehydrogenase, lipoprotein lipase and hepatic lipase. Superoxide dismutase activity increased with increasing dietary ARA levels. Glutathione peroxidase and catalase activities and malondialdehyde levels in liver tended to increase with increasing dietary ARA levels from 0.6 to 32.7 g ARA kg^?1 total FAs then declined when dietary ARA levels further increased to 64.8 g ARA kg^?1 total FAs. Broken‐line regression analysis of SGR against dietary ARA level indicated that optimal dietary ARA requirement for juvenile S. hasta was 10.74 g kg^?1 total FAs.