The latest scientific developments and technology applicable to modern sheep breeding will now be incorporated in a newly developed Genetic Evaluation by SA Stud Book for the Merino breed.

It will be implemented, with approval of the Merino Technical Committee, and made available to Merino breeders from April 2018 onwards.

The newly developed Genetic Evaluation will include the following:

• Breeding values and accuracies for Wean Direct, Wean Maternal, Number of Lambs Weaned, Total Weight of Lambs Weaned, Age First Lambing, Inter Lambing Period, Body Weight, Clean Fleece Weight, Fibre Diameter and Staple Length. These breeding values and accuracies are estimated with comprehensive multi-trait genetic models to calculate the genetic merit of animals more accurately. Heritabilities and genetic correlations have been re-estimated, using these comprehensive models, to cover the complete genetic variation of the current Merino population.
• Inbreeding coefficients will be routinely calculated for all animals included the Genetic Evaluation. These inbreeding coefficients will be based on all available generations’ information.
• Genetic Reports are newly developed for all breeders that participate in Logix

Production Recording, which include the following:

• Genetic levels (all traits) of the herd in comparison to the breed for all traits and indices.
• Genetic trends (all traits) of the herd in comparison to the breed.
• Assessment of inbreeding of the herd in comparison with the breed
• Top-lists for Sires used in the Flock, active measured rams, active young rams and ewes of the flock.

Breeding values and accuracies will therefore be adjusted in the new release of April 2018 due to the more comprehensive models and newly estimated genetic parameters being used. Ranking of the animals will, however, not be significantly changed. The newly developed breeding values will ensure that genetic differences between animals can be determined with greater accuracy. Furthermore, the Genetic Reports enable Merino breeders to make more informative decisions faster. This, in turn, which will lead to more efficient achievement of breeding goals.

Source: SA Stud Book and Merino SA