Last update: August 12, 2011 04:09:41 PM E-mail Print

 

RESPONSE TO SELECTION ON BLUP OF BREEDING VALUES

IN THE GROOTFONTEIN MERINO STUD

 

J J Olivier

Grootfontein Agricultural Development Institute, Middelburg 5900

G J Erasmus, J B van Wyk & K V Konstantinov

Dept. Animal Science, University of the OFS, Bloemfontein 9300

 

Visual appraisal still plays an important role in selection of rams in the Merino stud industry. In the Grootfontein Merino stud, selection on visual appraisal was practiced up to 1984 with the main objective to increase fleece and body weight as well as subjectively assessed wool and body. traits. From 1985 selection was based on BLUP of breeding values for mature body weight (BW), clean fleece weight (CFW) and mean fibre. diameter (MFD) combined with a high culling rate on visual appraisal. The. breeding objective was the same as in the previous period except that CFW was maintained and MFD decreased. The genetic trend from 1966 until 1984 was 0.2048 kg (R2 = 0.8183) for BW, 0.0242 kg (R2 = 0.8930) for CFW and 0.0269 micron (R2 = 0.5496) for MFD. From 1985-1991 the genetic trend for BW was 0.6314 kg (R2 = 0.9436, 0.0014 (R2 = 0.0052) - for CFW and -0.1574 micron (R2 = 0.8433) for MFD. It is concluded that. selection on BLUP of breeding values in a commercial Merino stud can lead to a marked increase in genetic progress in economically important traits, in spite of the limitations posed by high culling rates on visual appearance.

 

Published

Proceedings 34th SASAS congress.South African journal of animal science 25 (1)