摄食量对非洲胡子鲶及其杂交种生长的影响

Effect of feed intake on growth of African catfish and their reciprocal hybrids

本文系两种非洲胡子鲶Clariasgariepinus（C.g）和Heterobranchuslongifilis（H．l）以及它们的正反杂交种，在封闭式养殖系统下，不同摄食量对其生长影响的研究。40d的试验结果表明：（1）死亡率和体重差异系数只与交配亲鱼有关（p＜0．001），其中以C．g（F）×C．g（M）纯种最低；（2）各组在投食量（16～21）×（10－3m／m）0.8／d时，饲料系数均显最低。而C．g（F）×H.l（M）杂交种是4组中最低的；（3）各组可达到的最大摄食量存在显著差异（P＜0．001）。其中以C．g（F）×C．g（M）最高，C．g（F）×H．l（M）杂交种次之；（4）个体生长率和代谢体重相对生长率随着摄食量的增加而增加。其中以C．g（F）×C．g（M）最高，而C．g（F）×H．l（M）杂交种与之相比没有显著差异。C．g（F）×H．l（M）杂交种表现出一些良好的特性。

African catfish Clarias gariepinus, Heterobranchus longifilis and their hybrids are cultured in a recirculation system. Different feeling levels affect their growth patterns. The results after 40d of experiment are as follows. (1) Mortality and body weight coefficient of variation were only affected significantly by different crosses (p < 0. 001 ); (2 ) The lowest feed conversion (FC) given at feeding level was around (16~21 )× (10-3m/m )0.8/d in all the four crosses,and FC 0. 51 in the hybrid C- g (F) ×H. l(M) ;(3) Maxlmum feed intake was significantly different with crosses; (4) Speciflc growth rate (SGR) and relative growth rate of metabolic weight (RGR.m ) increased with the increase of feeding levels. C. g ×C. g cross had the highest SGR and RGR.[9. 3%BW/d and 73. 4×(10-3m/m )0.8/d]and C- g×H. l hy-brid had no significant difference from it- C. g ×H. l showed some good characteristics.