Background,The detail structure of chromosomes depicted by their banding pattern is very useful in drawing homology and analogy in the structure of chromosome within and between the species.
Results, In the present study, the diploid  number of chromosomes was 50 in the  fresh water teleost, Clarias batrachus in which 18 metacentric, 20 submetacentric and 12 telocentric chromosomes were observed. Structurally, the G bands revealed that transverse bands were visible after banding. These were due to the presence of heterochromatin and presence and absence of bases, these bands were observed at two pairs of submetacentric chromosomes. The NOR bands on the chromosomes were detected by silver staining in the two pairs of medium size telocentric chromosomes. It was believed that silver staining bound with the non-histone proteins of the transcriptionally active NOR region.
Conclusion, Our results showed that basic information of chromosome number and morphology with G and NOR banding can be used as an important tool for cytogenetic data of fresh water teleost Clarias batrachus.