New technology breakthrough identifies level of immunity

Sires with a higher natural level of disease resistance will soon be available for farmers to buy, thanks to the latest technology.

Cattle genetics suppliers, Semex, are to sell sires identified as having high immunity - a trait that can be passed on to their offspring in the same way as other inherited traits - under a new brand, immunity+.

Research led by Dr Bonnie Mallard, of the University of Guelph, Canada, found that cows with High Immune Response (HIR) are two to four times less likely to contract diseases than those cows with Low Immune Response (LIR).

The HIR technology identified cows with levels of immune response to diseases such as mastitis, metritis, ketosis, retained placenta and Johne's disease. Those cows with high immunity have a 25 per cent chance of passing the trait on to their offspring.

The company says the new technology "marks a significant breakthrough in improving disease resistance in cattle which will reduce the use of remedial medication".

Managing Director Gordon Miller added: "Trials have shown that using these high immunity sires can significantly reduce the percentage of disease in a herd, which we estimate will be worth about £50 per cow."

HIR testing takes place over two weeks, involving blood samples and skin thickness tests, and the animals are immunised in a similar way to a vaccination that stimulates the immune system.

Sires only need to be tested once in their lifetime to determine genetic immunity levels.

Due to the amount of money invested into the research, the test will be unique to Semex for the next ten years. The first two Immunity+ sires to be marketed are R-E-W Seaver and Charpentier LFG Spectrum.