A COMPARATIVE STUDY OF THE BIOLOGICAL CHARACTERS OF GYNOGENETIC CLONES OF SILVER CRUCIAN CARP (CARASSIUS AURATUS GIBELIO)

This paper describes a comparative study of the biological characters of four gynogenetic clones, A, B, C and D of silver crucian carp. Clone D hnas the greatest body depth, With a relative body depth (body depth/body length×100%)of about 47%. The relative body depth in clone A, B and C is 44.4%, 41.7% and 43.7% respectively. Clone D exhibits the highest growth rate, its growth rate is 14.7% higher than that of clone A, which has the second highest growth rate. Results from the present study and the experiments in 1987 indicated that the growth rate in the four clones were in the order clone DACB, and growth rates in their allogynogenetic offsprings were in the order clone D≥ACB. There was not significant difference on the muscle content or the protein content of the muscle among the clones. Apparently, clone D was able to utilize the food with a higher efficiency than clone A. It was estimated that use of allogynogenetic crucian carp from clone D for culture world increase the economic value by 10—20%. Ovary development was different in the four gynogenetic clones. Clone D showed a phase of rapid oocyte development in February and entered ovary maturation in mid—March. Clone A entered ovary maturation between the end of March and the begining of April, and clone C between mid—April and the begining of May. The crucian carp spawn several times in a spawning season. The fish of clone D, after the first spawning, can spawn for the second time after a period of culture in ponds. Inter—clone difference also existed in the number of chromosomes. The number of chromosome is 162 in clone D and 156 in clone A and C.