Selected Brahman project
The aim of the Selected Brahman project is to help northern beef cattle producers improve fertility rates in Bos indicus cattle through a focus on genetic improvement. Producers will be better informed about how selection can influence herd fertility and in turn maximise productivity gains.
The study is being conducted using breeder cattle from the Northern Territory Government’s Brahman stud at the Victoria River Research Station and Douglas Daly Research Farm. The research has shown that selection has improved fertility in Brahman cattle. Selection pressure has been applied to both bulls and cows in the herd and this has more than doubled yearling heifer conception rates compared to heifers from four commercial herds, when assessed over four different seasons. Also pregnancy rates in lactating breeders were found to be more than 30 percentage units higher in the Selected Brahman herd than in a commercial herd run on the same property.
Selection criteria for the project:
- Cows are culled from the herd if they do not raise a calf to weaning each year. Raising a calf to weaning age each year proves maternal traits of calving ease, mothering ability and milk production while maintaining good body condition ready for re-conception each year.
- Young bulls are selected at 12 months of age using a selection index based on scrotal size, 400-day weight, percent normal sperm, low age dam at first calving and the dam’s ‘never miss a calf’ score. These bulls are retained in the herd for natural mating services.
- New genetics are carefully selected from herds that cull empty cows each year. Semen is used from bulls with low ‘days to calving’ and high scrotal size EBVs to AI two-year-old heifers in the herd.
Yearling mating is used to identify highly fertile females. Brahmans are notorious for taking longer to reach puberty than Bos taurus breeds. This selection technique favours individual females that reach puberty earlier than the breed average.
When: The selection for fertility using BREEDPLAN began in 1994 and is ongoing.
Where: Victoria River Research Station, 220km south-west of Katherine, and Douglas Daly Research Farm, 220km south-west of Darwin.
RD&E objective: Enterprise viability; increasing cost efficiency, productivity and profitability
Industry priority: Reproduction
Factsheets and field day materials
- Selected Brahmans: selection for fertility works (DOCX, 1MB), Tim Schatz, Department of Primary Industry and Resources, as presented at 2012 Kidman Springs Field Day.
- Schatz et al. (2011) Selection improves fertility in a Brahman herd. Proceedings of the Northern Beef Research Update Conference, 3–4 August 2011. Darwin Northern Territory, page 118.
- Golding et al. (2011) Breeder fertility improved through selection in a NT Brahman herd. Proceedings of the Northern Beef Research Update Conference, 3–4 August 2011. Darwin, Northern Territory, page 118.
- Impressive increase in Brahman fertility in NT case study (PDF, 661KB), Beef Bulletin Q1 2012.