Comparison of Highly Fertile Ewe Crossbreeds

Summary

The trial indicated that EF ewe fertility was similar to BoolL ewes and slightly better than EF x BL ewes, or BL ewes. Differences observed were lower than anticipated. Pre-weaning growth rates of lambs from EF ewes were superior to the other genotypes in the trial, which may be attributed to better milk production of the EF. In the first year, EF x M ewes produced 20% greater weight of lamb per ewe mated than the other genotypes. The superior performance of the EF x M ewes decreased significantly over the trial, questioning its long term sustainability would be sustainable long term. The weight of lamb weaned per ewe mated was similar for the (BL x EF) x M and BL x M ewes which is surprising, given the weight of the lamb per ewe mated advantage of the EF x M ewes. An estimate of the weight of lamb produced on a per hectare basis was not possible because of the movement of the flock throughout Nangwarry Station.