Abstract :
India is rich in sheep biodiversity. Patanwadi, Marwari and Dumba are three important
breeds of Gujarat. Dumba is a pastoralist breed with a majestic look, which is extensively
used for crossbreeding with Patanwadi and Marwari ewes. Microsatellites were used to
ascertain genetic variability, bottleneck and population structure using 20 microsatellite
markers. The total number of alleles observed was 165, 181 and 160 in Patanwadi, Marwari
and Dumba, respectively, depicting a wide range of variability. The overall heterozygosity,
polymorphic information content (PIC) and Shannon index values were 0.62, 0.65 and
1.63, indicating high genetic diversity. The FIS estimate reflected a high rate of inbreeding.
Non-significant heterozygote excess on the basis of two-phase model (TPM), along with
a normal ‘L’-shaped distribution of mode-shift analysis test, indicated an absence of bottleneck.
Population structure analysis revealed five different clusters and intermixing of
individuals from three breeds in each cluster. The information generated from the present
study will be valuable for setting conservation priority of the less-described breeds such as
Dumba and will also add to the knowledge of previously characterised breeds