Ulmek, B.R.Hadawale Nilisha Parashuram2019-10-162019-10-162008http://krishikosh.egranth.ac.in/handle/1/5810131381The present research work “Cytogenetic characterization of ‘Phule-Triveni’ crossbred cattle” was undertaken to characterize the breed on cytological level. Phule Triveni cross-bred cow strain, developed at MPKV, Rahuri is a triple cross-bred cow having blood level of HF (50 %), Jersey (25 %) and Gir (25 %) and karyotyping of this strain can help in screening breeding bulls for existence of hereditary diseases caused by detectable chromosomal defects. Elimination of such abnormal animals will help to maintain the herd cytogenetically clean. A total of 20 ‘Phule-Triveni’ cattle (10 males and 10 females) maintained at Research Cum Development Project on Cattle, MPKV, Rahuri were utilized for the present investigation. The chromosome preparation were made by using short term peripheral blood lymphocyte culture technique.The number of chromosomes were counted in about 10 metaphases per animal and best metaphases for each sex were photographed and karyotypes were prepared. The length of chromosomes was measured using vernier calipers with an accuracy of 0.02 mm. The relative length of a chromosome was measured as the ratio of its length to the total length of haploid chromosome set containing an x-chromosome and then expressed as percentage. The idiograms were drawn using relative length of chromosomes. The arm ratio was computed as the ratio of length of short arm (p) to the length of long arm (q). The centromeric index was calculated as the ratio of length of short arm (p) to the total length of a chromosome (p + q). The diploid chromosome number for Phule-Triveni crossbred cattle was found to be 60. All the 29 pairs of autosomes were acrocentric in nature, whereas X-chromosome was submetacentric. The Y- chromosome of Phule-Triveni cattle was acrocentric in morphology. The first pair of chromosome contributed 5.545 per cent in male genome and 5.540 per cent in female genome, whereas, the last pair contributed 1.571 and 1.623 per cent in males and females, respectively. In Phule-Triveni males, X chromosome contributed about 5.499 per cent to total genome whereas, Y-chromosome contributed about 1.524 per cent. The arm ratio of X-chromosome in the present investigation was found to be 0.57 per cent and centromeric index There was significant effect of sex on the mean relative length of chromosomes of Phule-Triveni cattle. The present study revealed that the chromosome architecture of Phule-Triveni cattle was similar to that of the other breeds of zebu cattle.ennullThesis