Life Sciences Commons^™

Reproductive Wastage In Sheep, R W. Kelly

Journal of the Department of Agriculture, Western Australia, Series 4

The average lambing performance of Western Australia's ewe flock fluctuates between 60 and 70 per cent. Although this level of performance and variation between years is important for the sheep industry, individual farmers are more concerned about performance of their own flocks.

Figure shows the range in lambing performances that exist between farms in this State in 1983-84. The seriously poor performance of many flocks is apparentm - 28 percent of farms had less than 60 per cent lambing. By contrast, 24 farms had performances better than 100 per cent. The reasons for the large differences between farms ( and …

Ovulation Rate Of Ewes : Role Of Energy And Protein, E Teleni, J. B. Rowe

Journal of the Department of Agriculture, Western Australia, Series 4

Western Australia's sheep farmers are familiar with the low ovulation rate of Merino ewes and how this limits the lambing performance of ewe flocks.

One way in which ovulation rate and therefore lambing percentage may be increased is to feed seed of sweet lupin (Lupinus augustifolius) to ewes at mating. However, Department of Agriculture research has found that these increases do not show up consistently, and that there is considerable variability between farms.

If improved nutrition is to be a useful way to increasing ovulation rate, the mechanism by which nutrition affects ovulation rate must first be understood. This article …

Reproductive Wastage Among Merino Ewe Flocks. 2. Non-Clover Areas, T Marshall, B. R. Beetson, R. J. Lightfoot, G. R. Mcmullen

Journal of the Department of Agriculture, Western Australia, Series 4

This research sought to define the reasons for low fertility among Merino ewes in Western Australia.

This first article looks at wastage in Non-Clover areas

Reproductive Wastage In Sheep In Non-Clover Areas, C. H. Trotman

Journal of the Department of Agriculture, Western Australia, Series 4

A Research Round-up report in the June, 1972, issue of the Journal of Agriculture discussed the reproductive performance of sheep in Western Australia and indicated that more than 20 per cent, of mated ewes fail to lamb.

The report presented the first year's results from sheep grazing clover areas.

This report presents results from the nonclover sections of the investigations

Sheep Fertility In Western Australia, R J. Lightfoot

Journal of the Department of Agriculture, Western Australia, Series 4

Why do one-quarter of the ewes that are joined in W.A. fail to lamb? Sheep and Wool Adviser Dr. R. J. Lightfoot analyses the eight stages in sheep reproduction, explaining the causes and possible prevention of infertility at each stage.

Pasture Legume Varieties And Ewe Fertility, T Marshall, H. E. Fels, H. G. Neil, R. C. Rossiter

Journal of the Department of Agriculture, Western Australia, Series 4

ALTHOUGH it was first thought that all varieties of subterranean clover would cause ewe infertility, research in the last 10 to 15 years has shown that varieties differ in potency.

The relative level of potency has also been shown to remain consistent for any one variety under normal conditions.

High Pre-Mating Liveweights Improve The Lambing Performance Of Merino Ewes, R J. Suiter

Journal of the Department of Agriculture, Western Australia, Series 4

Analysis of lambing trials with Merino ewes has shown a highly significant association between pre-mating liveweight and lambing performance.

With May-June lambing ewes there was a 2.9 per cent, lambing increase for every extra 10 lb. liveweight; for July-August- September lambing ewes there was a 6.9 per cent, increase for every 10 lb. liveweight increase.

With the May-June lambing there was a critical weight below which twinning was negligible.

Time Of Lambing, W L. Mcgarry, I. K. Scott

Journal of the Department of Agriculture, Western Australia, Series 4

THE time chosen for lambing depends on many factors, and the final decision rests with the individual flock-owner who has to consider how different times fit in with the overall programme of farm operations; how they will influence the marking percentage, the marketing, the thrift of his sheep and most important, how they influence the profit from his sheep operations.