Comparative karyological and serological studies on some cichlidae fish

The present work carried out on Tilapia nilotica, Tilapia aureu,and Tilapia zilli in an attempt to compare between them through:- ’:;studying the standard karyotype and some chromosomal studies ofthe three fish species.- Differentiate between males and females of the three fish speciesby G-banding techniques.- Differentiate of the protein banding patterns by serum proteinelectrophoresis.The obtained results can be summarized as follow:I-THE KARYOLOGICAL STUDIES:Investigation of the karyotype of all the three fish species showedthat, they had 22 chromosomal pairs and the normal diploidchromosome number was 44.The length of Sh011 arm, the length oflong ann, the total length, the relative length, centromeric index, andarm ratio for each species were calculated.The chromosomes of all the three species form a homologouspairs; the morphological distribution of the karyotype of thesespecies is nearly the same.There were a few differences were found between the sizes ofchromosomes of the different studied species, the average size of