Increasing prolificacy and ewe efficiency in sheep through FecB gene introgression.

The FecB gene of Garole (G) was introgressed into non-prolific Malpura (M) sheep and the performance of the GM half-breds is being monitored. DNA samples of Garole, Malpura and Garole x Malpura (GM) crossbreds were screened by PCR-RFLP to determine the presence of FecB mutation. The majority of Garole (96%) and GM crossbred (72%) were carriers (BB and B+) for the FecB mutation. The FecB BB and FecB B+ carrier ewes resulted in 81.19 and 69.31% higher prolificacy respectively, as compared to non-carrier Malpura ewes. The viable benefits accrued by gene infusion are reflected by 45.7% increase in the prolificacy and 35.05% in weaning rate of GM compared to that of Malpura. A single mutated copy of FecB gene produced 0.70 and weaned 0.58 extra lambs in GM sheep. Likewise, the ewe productivity efficiency and ewe efficiency in terms of lambs' weight produced per kg of ewes' body weight of FecB carrier GM ewes showed upward trend during the growth phase as compared to non-carriers. The FecB carrier twin lamb bearing ewes weaned 78.38% more lambs compared to non-carrier ewes. The DNA test should be applied in routine as a marker for identifying FecB gene in crosses with Garole sheep.