Genetic diversity of a nucleus flock of Malpura sheep through pedigree analyses

Malpura sheep is one of the heaviest sheep breed of India, known for its adaptability to harsh environment and potential for high meat production. It is distributed in the semi-arid region of Rajasthan, India. The pedigree information estimated by the number of equivalent generation traced was good (7.21). For reference cohort, effective number of founders (fe) was 58, representing 29.15% of the potential number of founders. The effective number of ancestors (fa) was 36 and the genetic contribution of the 13 most influent ancestors explained 50% of the genetic variability in reference cohort. The realised effective population size of the flock was 91.74 ± 2.02. The ratio fe/fa which expresses the effect of population bottlenecks was 1.61. The average inbreeding coefficient for reference population was 3.32%. The average relatedness coefficient between individuals of the reference population was 5.10%. The generation interval was lowest for ram daughter pathway (2.72 years) and highest for ewe to son (4.13 years). Study revealed non-significant effect of individual inbreeding or change in inbreeding on the lamb live weights. Introduction of new sires with the lowest possible average relatedness coefficient and the use of appropriate mating strategies are recommended to keep inbreeding at acceptable levels and increase the genetic variability.