Myostatin testing has been introduced by several beef breeds as another selection 'tool' for beef farmers, and while the majority of farmers have little knowledge of what the gene is or how it operates, the Salers Cattle Society has made the decision to eliminate it from their herdbook within the next five years.

The gene, which is associated with double muscling and is recessive in all mammals, influences the production of a protein that controls muscle development. Natural mutations cause a deletion in the bovine myostatin so the muscles keep growing, resulting in the double-muscled phenotype.

However, while double muscled calves regularly command a premium in the market place, breeding from cattle with this extra muscle often results in calving difficulties and reduced fertility – the exact opposite of the Salers which is renowned for it's wide pelvis and unrivalled calving ease.

Hence, the decision to make the breed 100% free of these mutations which to date have only been found in very small proportion of cattle, has been made.

"The Salers is one of the fastest growing breeds in the UK and we have to protect the breed's maternal, fertile, ease of calving characteristics," said Tom Walling, chairman of the Salers Cattle Society.

"Testing of individual bulls over the years and their family lines, show there are only 17 with the NT82L gene which is one myostatin that has been shown to cause calving problems in Charolais and Limousin, and has already been banned in Salers in France, so we are in a good position to protect the UK Salers population from cattle with myostatin genes.

"Trials have shown double copies of the gene (from the dam and sire of a mating programme) reduce fertility and the size of the testicles while also shortening the bones in the pelvis thereby affecting calving ease in the progeny. We just cannot afford to let such genes ruin the Salers which is renowned for it's ease of calving," he said.

The starting point to make UK Salers 100% myostatin free was the discovery by the French Salers Society that a couple of the myostatin mutations had infiltrated the breed from the Charolais and Parthenais. These were found in about 1% of animals tested.

The French took the decision to eliminate them and implemented a programme of mandatory testing of bulls and don’t allow bulls with these mutations to be registered. Subsequent testing of Salers in the UK revealed the presence of the mutated genes in a small number of animals descending from four French animals.

Following consultation with members, in March 2019 the council of the Salers Society decided that there is no place for these mutations in the breed. To give breeders time to tidy up their herds, the deadline of January 1, 2024 was set, from which no registrations will be accepted for animals with any of the myostatin mutations. Great progress has been made with almost 1200 animals achieving M0 status in five months.

In the interim, to ensure that purchasers of breeding stock have the information, all bulls must be tested to be registered, as must all entries to society sales. The myostatin status will be shown on the pedigrees and in the sale catalogues, where a status of M0 or M0P indicates an animal is free of the mutations, M1 means an animal has a single copy and M2 means it has two copies of any of the mutations.

Making the myostatin status known to commercial suckler farmers it vital, as the worst effects of the myostatin mutation on calving ease etc. occur when an animal inherits two copies, one from each parent.

Suckler farmers can avoid this risk by keeping cows that are M0, whilst still being able to use a strongly muscled terminal sire to gain improved conformation, as the resulting calves will at most have just one copy.

The Salers Cattle Society believes making the Salers an M0 breed in addition to its unrivalled ease of calving, milkiness and fertility, will protect its industry leading position as the ultimate suckler cow.