Categories
vol-22KARYOLOGICAL STUDIES ONAFRICANCATFISH,
Clarias gariepinus ( Burchell, 1822)
By
SH. A. BAKHOUM*
*National Institute of Oceanography and Fisheries, Alexandria, Egypt.
Key words: Genetics, Cat fish.
ABSTRACT
Karyological studies on African catfish Clarias garzeplnus
originating from the Egyptian inlandwaters (Lake Mariut) have been
done to determine ifit reveals an identical karyotype to the other strains
of this species or not. The diploid chromosome number was found to be
56 chromosomes, length rangedfrom 1.70 to 6.90 pm, the total length of
the chromosome set was 105 pm. Fundamental numberfor male and
female were 88 and 87 respectively. The modal karyotype for male
consisted of 14 metacentric, 18 submetacentric and 24 acrocentric
chromosomes while that of female revealed 14 metacentric, 17
submetacentric and 25 acrocentric chromosomes. These differences in
morphological distribution of the karyotype between male andfemale
were attributed to the sex determination ofthis species belong to the ZZ
– ZW system i. e. female karyotype contains a large submetacentric
chromosome and a small acrocentric chromosome as compared to that
pair ofsubmetacentric chromosomes in male.
