- Economic returns of Merino ewes selected according to three different selection methods
|Last update: August 18, 2011 12:02:07 PM|
ECONOMIC RETURNS OF MERINO EWES SELECTED ACCORDING TO THREE DIFFERENT SELECTION METHODS
J.J. Olivier & G.J. Delport*
Grootfontein College of Agriculture,
* SA Fleece Testing Centre, Middelburg
The effectiveness of three different selection methods to maximize economic returns in Merino sheep was investigated. A total number of 120 18-month old Merino ewes were available. Of these 66% were identified to be selected by the following methods:
- Subjective method.
- Index selection (I=body mass + 25 x clean fleece mass - 9 x fibre diameter - 5 x pleat score).
- Ewe productivity (3 x wool mass + total mass of lambs weaned after two lambing seasons).
After two lambing seasons the annual gross income from products (meat and wool - 1987/88 prices) of ewes selected by subjective methods was R132.66, that of ewes selected by a selection index R132,75 and that of ewes selected by ewe productivity R139,39. These small differences in the gross income of ewes selected by the different methods can be attributed to low selection intensity for the different production traits which is normally found with ewe selection. The effects of the different selection methods on income from the future generation is not clear and needs investigation.
Proceedings 28th SASAP congress