大阪鲫生物学的研究

本文对大阪鲫的生物学特性进行了研究，主要内容包括：(1)形态特征、生活习性、繁殖习性、食性和胚胎发育的研究；(2)生长速度、起捕率、疾病的试验；(3)丰满度、肌肉的营养成份和氨基酸的测定；(4)染色体、血清蛋白电泳的分析等。同时还将上述各项同东北鲫、本地鲫进行了比较。大阪鲫的性比为1：1，与东北鲫、本地鲫不同。大阪鲫的鳃耙个数多(最多可达120个)，且长而密，其侧突而长分枝，鳃耙与鳃丝等长。成鱼的肠管长度为体长的5．6倍，管细、壁薄、迂回盘曲。大阪鲫的食性广阔，是属于兼食浮游植物的杂食性鱼类。大阪鲫的染色体与本地鲫相同，都是2n=100。大阪鲫具有明显的生长优势，比本地鲫生长快12—46．2％。它的起捕率很高，可达90％以上，比东北鲫(50％)、本地鲫(5％)高得多。大阪鲫的丰满度为3．07—3．24，空体壳占体重的百分比为85—86％，具有较好的经济性状。肌肉中蛋白质、脂肪的含量与本地鲫、东北鲫相近，而水份含量略高于东北鲫，本地鲫。丝氨酸、精氨酸、谷氨酸、丙氨酸、亮氨酸等的含量均比东北鲫、本地鲫略高。大阪鲫的生长速度快，群体产量高，食谱广，经济性状良好，是一种淡水养殖的优良品种。

BICLUGICAL STUDIES DN WHITE CRUCIAN CARP (CARASSIUS AURATUS CUVIERI)

This paper deals with the biological characteristics of white cru-cian carp (Carassius auratus cuvieri), which includs (1) Studies on its morphologicalcharacteristics, liing habit, reproduction feature, feeding habit and embryonie deve-lopment;(2) Experiments on its growth speed, catching rate and disease(3)Mea-surement of fattiness, nutritional composition and the content of amino acid in muscle; (4) Analysis of chromosome and serum protein electrophoresis. Besides, the compari-son between different variety of crucian carp is also made. The sex ratio of C. auratus cuvieri is 1:1, which is different from that of C.auratus gibelio or C. auratus, a local variety. C. auratus cuvieri has more gill rakes (the maximum can be 120 rakes) whichare long and dense, and of same length with the branchial filament. The lateralswelling of the gill rake is both long and branched. The intestines of the adult fishis thin and twisted, the length of which is 5.6 times of the body length. Theintestines wall is also thin. The fish has a wide feeding habit.belonging to omnivorousspecies which feed on phytoplanktons too. Both C. auratus cuvieri and C. auratusgibelio have the same chromosome, being 2n=100. C auratus cuvieri growes 12--46. 2% faster than a auratus and its catching rateis as high as over 90%, much higher than that of C. auratus gibelio (50%) or C.auratus (5%). Its fattiness is 3. 07--3. 24, and as the empty weight of the fish accou-nts for 85--86% of the total body weight, this variety of crucian carp has a bettereconomic value. The contents of protein and fat in muscle of C. auratus cuvieri aresimilar to those of C. auratus gibelio or C. auratus, but its Water content is a Iittlehigher. The contents of histidine, arginine, glutamic acid, alanine, leucine etc. of C.auratus cuvieri are atso a little higher than those of the other two varieties. In general, C. auratus cuvieri has a faster growth rate and a wide fecding habit.Its population yield is also high, so the fish has a better economic efficiency and is anexcellent variety for warm water fish culture.