Kara Knudsen admits it's a case of trial and error when finding the most suitable bulls for her 3500-head beef operation, but a multi-breed approach to using estimated breeding values could take the guesswork out of that problem.
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The Nuffield scholar and owner of Knudsen Cattle spoke about the potential benefits of multi-breed EBVs in the north at the Repronomics and Northern Steer BIN Project seminar at Beef 2024 on Wednesday.
The proposal would mirror the Southern Multi Breed program in NSW, which provides the base herds for an accurate reference population for multi-breed genetic evaluation.
The Queensland-based grazier owns almost 70,000 hectares across two aggregations at Mundubbera and Chinchilla in the south, and at Hughenden in the north.
Her scholarship looked at Accelerating genetic progression in the north Australian beef herd.
"We can only use EBVs within their own breed so for us as commercial breeders, we use crossbreeding and really value what we can get out of crossbreeding," Mrs Knudsen said.
"However, we're really not able to assess what a bull from a different breed would bring to the herds in comparison to what we've already got."
The Elton Downs operation in the north is based on a Bos indicus herd where Santa Gertrudis, Angus and Santa Gertrudis/Shorthorn-cross bulls are used over breeders purchased with unknown genetics.
In the south at the Rosehall Aggregation, the Santa Gertrudis base is joined to the same array of bulls.
"It's really been trial and error to see what those crosses do, but we don't get too out there and we try to just maintain a consistent weaning line so they're easy to market," Mrs Knudsen said.
"Something like a polled calf is easy for us to assess because we can measure the percentage of calves every year that are polled and see that it is increasing.
"Fertility in our heifers though is very difficult to know whether we're getting better each year because of the nutrition, supplementation and the other management changes that we might make early on.
University of New England Animal Genetics and Breeding Unit principal research scientist David Johnston, the person who has overseen the Repronomics and Northern Steer BIN Project, said multi-breed EBVs would allow graziers to compare cattle across multiple breeds.
"Currently, EBVs are only comparable within a breed and a multi-breed EBV would allow particularly commercial producers to compare bulls across breeds," he said.
"There would be a number of benefits to this and the first is they're buying bulls and just want to make sure they're getting one that meets their profitability and market specs.
"They might say is this Santa bull going to be appropriate or can I directly compare it with this Droughtmaster bull?"
Dr Johnston said it would allow graziers to more effectively manage their cross-breeding operations, and select bulls based on benchmarked data.
"At the moment you don't know whether the average of the two breeds is the same or if they're vastly different," he said.
"The theory and the technology has been there for a long time and we do it in our sheep breeds, but what we lack in beef is that head-to-head comparison."
The Southern Multi Breed program in NSW is based across five sites and features the breeds of Angus, Hereford, Shorthorn, Charolais, Wagyu and Brahmans.
He said a similar project in Queensland would require the collation of Breedplan data and the support of the breeds' societies
"If we're going to bring the data together to make a multi-breed EBV, we've got to bring the societies and their members with us," he said.
"We have other breeds wanting buy in so it shows there is really good demand with this."
Dr Johnston confirmed after the seminar Meat & Livestock Australia would financially support the Repronomics project for another four years.
Funding for the project was set to expire at the end of June 2024.
The project has been responsible for establishing new EBVs for hard to measure traits, improved EBV accuracies on young bulls from 30 per cent to 50pc for days to calving and increased the number of Brahman bulls being sold with a days to calving EBV.
"MLA has committed to continuing this project through its MLA Donor Company and we're currently working with DAF in securing that project at the research stations to continue," he said.
"It hasn't actually been announced because we don't have the details, but we're waiting to get the final work with DAF before we announce it officially.
"There is in-principle support for that to occur and within the next two months, the devil will be in the detail."