More lambs from feed and chemical treatments

The ovulation rate, or the number of eggs shed per ovulating ewe, represents the upper limit of the capacity of a flock of ewes toproduce lambs. Several methods can be used to increase ovulation rates and lambing percentages of ewes, including selection for better breeding, feeding and the use of chemicals. The potential for improving the reproductive performance of Western Australia\u27s ewe flocks by the use of different approaches to breeding was discussed by L.G. Butler and R.P. Lewer in the Journal of Agriculture in 1983. This article mainly discusses the research conducted by the Department of Agriculture\u27s Sheep and Wool Branch on the supplementary feeding of ewes with sweet narrow-leafed lupin seed (Lupinus augustifolius) and the more recent investigations of the technique of immunisation to change the levels of some of the sex hormones in ewes. Both methods can increase ovulation rates and subsequent lambing percentages