Increasing the ovulation rate in ewes by immunisation

J.F. Smith, R.I. Cox, L.T. McGowan, P.A. Wilson, R.M. Hoskinson

Ruakura Animal Research Station, Hamilton and Ian Clunies Ross Prospect Laboratories, Blacktown, NSW, Australia

Proceedings of the New Zealand Society of Animal Production. 1981, 41: 193-197

The immunisation of Coopworth and Romney ewes against androstenedione and oestrone increased their ovulation rate by up to 30% and in the case of oestrone group this was reflected in a 27% increase in the number of lambs weaned. The response to immunisation was additive to that obtained by increased pre-grazing herbage allowance for 6 weeks premating and to that between breeds.

Keywords: NZSAPAB;

Last Updated 12-09-1998