Positioning SA For The Future Of Beef Production

- Llewellyn Angus

One of the emerging technologies discussed at this year’s Beef Improvement Federation Research Symposium and Convention was the development of grazing distribution phenotypes. Derek Bailey, professor of range science at New Mexico State University, said in his presentation that grazing distribution of livestock was a critical trait. Trials had shown that certain cattle of the same breed, herd and production stage consistently preferred grazing in lower-lying areas (bottom grazers), while others preferred high-lying areas (top grazers).

According to Bailey, the selection of beef cattle for terrain use has the potential to resolve important grazing management issues in the US and elsewhere.

MATING DECISIONS

During a workshop on selection and mating decisions, beef genetics specialist Dr Matt Spangler, associate professor at the University of Nebraska-Lincoln, spoke about the impact of single-step evaluations on selection indices. He said that trying to blend classic estimated breeding values (EBVs) with genomic values into two-step genomic-enhanced breeding values (GEBVs) was problematic. With single-step evaluations, genomic evaluations are considered simultaneously with genetic evaluation, resulting in more accurate GEBVs with no bias towards EBVs or the genomic side. This implies that breeders should not only rely on genotypic data to determine GEBVs, but carry out accurate performance testing of the most important weights and traits, with correct management groupings. The combination of this data together with the genotypic data will deliver the desired GEBVs.

BULL SELECTION