ABSTRACT
India, one of the twelve mega biodiversity countries in the world, is home to large diversified cattle genetic resources, having 190.9 M cattle and so far 43 registered native cattle breeds. These cattle breeds are specially adapted to different agro-climatic conditions of India and their genetic diversity is due to the process of domestication over the centuries. There is decrease of 4.10% in cattle population and 3.14% in cattle genetic resources of India as compared to the quinquennial livestock census. The exotic / crossbred population has been increased by 20.18% during the period of last census while population of indigenous cattle has been decreased by 8.94% during the same duration. The reasons for depletion of native breeds includes crossbreeding with exotic breeds, economically less viable, loosing utility, reduction in herd size and the large scale mechanization of agricultural operation. The native breeds need to be conserved for genetic insurance in future, scientific study, as a part of our ecosystem, cultural and ethical requirements and for energy sources in future. The indigenous breeds of cattle posses various unique characteristics such as the presence of unique genetic variation in HSP70 gene family, carry a ‘thermometer gene’ and presence of A2 allelic variant in cow milk, which makes them well adapted to the tropical climate. The conservation includes the preservation along with up-gradation (improvement) of the genetic potential and management of a breed for use in future. The effective management of indigenous cattle resources includes identification, characterization, evaluation, documentation and conservation. The future strategy should be to combine genetic improvement and conservation. Establishment of regional gene banks and people’s participation by involving breeders, communities, gaushalas, NGOs and other relevant stakeholders in conservation programs. For more effective conservation measures, proper coordination and integration among various agencies (ICAR, SAHD, SAUs, SVUs and Research Institutes) is highly needed. “National Consortium of Partners’ comprising different stakeholders should be formulated for conservation of indigenous breed resources with a holistic approach.
ABSTRACT
Point mutations in exon IV of the bovine k-casein (CSN3) gene determine two allelic variants, A and B. These variants were distinguished by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis in the indigenous Sahiwal and Tharparkar cattle breeds. DNA samples (252 Sahiwal and 56 Tharparkar) were analyzed for allelic variants of the CSN3 gene. Polymorphism was detected by digestion of PCR-amplified products with HindIII, HhaI and HaeIII restriction enzymes, followed by separation on 3 percent agarose gels, and resolved by ethidium bromide staining. Allele A of the k-casein gene occurred at a higher frequency than allele B, in both Sahiwal and Tharparkar breeds. The genotypic frequencies of AA, AB, and BB in the Sahiwal and Tharparkar breeds were 0.758, 0.230 and 0.012, and 0.0.732, 0.250 and 0.018, respectively. The frequencies of alleles A and B in the Sahiwal and Tharparkar breeds were 0.873 and 0.127, and 0.857 and 0.143, respectively. Genotype BB of the kappa-casein gene had more influence on the monthly milk yield, 305-days milk yield, monthly solids-not-fat (SNF) yield, and monthly protein yield, in the Sahiwal cattle.