• ASHOK J. PATIL
• D.V. AHIRRAO

A survey of literature on karyotype analysis of female black rat (Rattus rattus) indicates that there is no unique consensus on number and morphology of chromosomes. Several workers have reported the diploid chromosome number (2N)in black rat as =38, 40 and 42. It was found that different strains of laboratory rats showed differences in the morphology of chromosomes. Because of the fragment demonstration of chromosomes polymorphism and the geographic variations at its karyotype, the black rat (Common house rat) has proved to be an interesting animal for chromosomal studies. The present investigation was undertaken with an objective of determining its diploid chromosome number and describing the nature of its chromosomes. The Rattus rattuswas administered with 0.02% of colchicine for inducing c-mitosis. After 2 hours of colchicinetreatment, the rat was sacrificed by using anesthetic ether and dissected out the femurs. Karyotype analysis was carried out following the method given by Yosida et al., (1965). The present experimental results indicated that the diploid chromosome number of Rattus rattusis 2n=38 and the karyotype formula is 16m + 4sm+ 16a + 2X.

Chromosomes, Karyotype,Rattus rattus

"KARYOTYPE ANALYSIS OF FEMALE RAT (RATTUS RATTUS) FROM AMALNER, (MAHARASHTRA)", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 3, page no.434-438, March-2019, Available :http://www.jetir.org/papers/JETIRAO06064.pdf

"KARYOTYPE ANALYSIS OF FEMALE RAT (RATTUS RATTUS) FROM AMALNER, (MAHARASHTRA)", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 3, page no. pp434-438, March-2019, Available at : http://www.jetir.org/papers/JETIRAO06064.pdf