ROCKLEY'S PHENOTYPIC AND GENOTYPiC DATA COLLECTION

Data collection is essential to the Rockley breeding program as we seek to balance genotypic and phenotypic information when selecting males and females for the stud. Phenotype – Our animals are assessed against seven elite breeding attributes and our elite weaner grading system. Genotype – Leaders when it comes to recording hard-to-measure traits, we collect the following data on each animal in the breeding program:

• Birth weights
• 200 Day Weights
• 400 Day Weights
• 600 Day Weights
• Mature Cow Weights
• Scrotal Size
• Days to Calving
• Calving Ease
• Eye Muscle Area
• Fat Depth
• Flight Time
• Percent Normal Sperm

Scrotal measurements at 400 days help assess the age of puberty. 600 day semen morphology is also assessed while days to calving helps measure how quickly a female can conceive when a bull is introduced. Mature cow weight after each calf is weaned is also recorded. Rockley’s entire herd is genomics tested and parent verified and each calf is tissue sampled at the time of birth weight recording.

The more information collected over time and the more bulls in the program, the more linkages can be made through their progeny and the higher the accuracy of the EBVs. This helps Rockley Brahmans with our selection, and is also of great value to buyers looking to improve specific traits in their own herds.

For example, highly heritable traits such as birth weight and growth rate have been used to select sires with low birth weight and fast early growth rate genetics. In a commercial setting, this combination increases the calving rate by reducing dystocia, and these calves will do well on pasture and meet or exceed market standards.