The challenge
The economic and welfare costs of cattle disease in Australian feedlots
Cattle who enter feedlots are exposed to a range of diseases for the first time and bovine respiratory disease, which costs the industry an estimated $40 million annually, is the most common disease cattle encounter in Australian feedlots. It's a complex disease which can be caused by a multitude of agents so pinning down the causes and effectively protecting all animals in a feedlot through vaccination can be difficult to achieve. Infectious disease costs the Australian red meat sector around $2 billion per year, causing significant animal welfare issues.
Consumers are increasingly aware of the health and welfare of the animals that produce their food and are concerned with the use of antibiotics to prevent and treat disease in production animals. Maintaining consumer confidence is critical to the future of the livestock industries.
Our response
More genetics, less antibiotics
Natural variation exists in the ability of cattle to resist disease. Using our immune competence test we can identify animals that generate stronger immune response and then select these to breed progeny with elite genetics that provides an enhanced natural ability to resist disease. This 'immune competence' is a measure of the strength of an animal's overall immune system and resilience, reflecting its ability to cope with disease challenges and bounce back from those challenges quickly.
We have shown that genetic selection of immune competent cattle can reduce the incidence of disease in Australian beef cattle, particularly in feedlots. It can not only improve animal welfare outcomes, but also reduce health costs. It also reduces the reliance on the use of antibiotics and chemicals in livestock production and improves profitability for producers and feedlot operators.
The results
Immune competence as a genetic selection trait
Along with our partners, Angus Australia and Meat & Livestock Australia, we measured the immune competence of progeny with known performance from the Australian Angus Sire Benchmarking Program throughout their time in feedlots. We found that the health-related costs for the low immune competent animals were around $105 per head. The highest immune competent animals stayed healthier, had a lower mortality rate due to disease and incurred only $5 per head in comparison.
In this study, low immune competent animals represented only 12 percent of all animals entering the feedlot but accounted for 35 per cent of the estimated health associated costs.
We've now identified the estimated breeding value (EBV) for Angus cattle, named ImmuneDEX, so farmers can add immune competence into the mix of genetic traits when selecting new sires into the future. This is a world first and ensures that Australian beef producers have the tools at hand to improve the health of their herds. We've also identified genetic markers associated with improved immune competence which will allow commercial Angus producers to predict the immune competence of individual animals in their herds based simply on a DNA sample.
It's also a bonus for consumers - healthier cattle is a great animal welfare outcome and it reduces the use of antibiotics and chemicals in our food production systems.