By Alasdair Macnab

We all love a good looking cattle beast, or anything good looking for that matter. What is good looking and what drives the decision of what is good looking?

Well, with humans, it’s that beauty is in the eye of the beholder. What drives it with cattle and sheep?

Let’s deal with sheep first. For years I bred Rouge and Texels and could not make head or tail of what made judges decide the range of good, bad or indifferent. I gave up showing as I had a regular customer base and gave up sheep as my back could no longer handle feisty young tups.

Cattle, now I can still do that. What is a good carcase in the eye of the beholder?

A few years ago I had a young bull to sell in Carlisle mart. I shared a pen with another breeder whose bull had a massive rear end. There was huge interest in this other bull. It was getting me down.

I asked a prospective purchaser what the attraction of this other bull was. He told me that big back end was a huge yield of prime steak. I begged to differ and pointed out where the steaks actually were and what he was looking at was stew and mince.

I was told I was talking rubbish. He had never heard of the saying the money is where the sun shines.

Oddly enough, I was on a beef suckler farm this week and had the same conversation. The farmer of some 50 years of very successful farming with sucklers, and his sons, did not know where the various cuts of beef were.

Why this subject this month?

A fair number of you will be looking to purchase a new bull this spring. No, this is not a veterinary lecture on care of bulls etc. No, no, no!

This is about something much more important. Something, which if our industry does not get its head around very quickly and understand it, it could mean the end of the suckler industry as we know it.

I am sure there will be a good degree of consensus that purchasing and to an extent the valuing of stock bulls and females, is driven by the judge in the showring.

Can the industry today regard the judge in the ring as someone who has their finger on the pulse of commercial beef production, the ear and eye of both the primary producer and the butcher, the person of skill and knowledge, unfazed by fashion (whatever that may be) who can select the animals most suited to making profit, surviving and delivering the part of the production system they are designed for?

Am I wrong in thinking this?

How many changes in breeding fads and fashions have we seen over our respective lifetimes?

Much as the dairy industry has grasped breeding technology and genomics, so must the beef industry. This is not to take the skill of judging a beast by eye away. This still remains core to the job.

Assessing locomotion, bone structure, correctness, breed type, defects and temperament are still key points.

Indeed, much of carcase genomics can be assessed visually if you know what you are looking for, unlike the farmers I mentioned above. Go to any prime sale ring and you’ll see visual carcase assessment in action. The butcher’s living depends on getting it right with his eye.

How many of you buy a tractor, or car by your eye? It plays a part in your decision but its figures play a greater role.

How many of you cattle breeders have been to an abattoir or butcher shop? How many have asked a butcher to visit your farm and tell you what is best for his business?

For as long as I can remember, we have watched cattle presented in the pedigree and commercial show ring become more and more extreme in shape and muscularity. What is driving this?

I would suggest two things. One is the competition to produce that beast with more and more muscle and ‘shape’. The other is what is producing that shape – the myostatin gene.

The myostatin gene – what is it?

Many of you may not have heard of myostatin. This is found in all mammals. It influences the production of a protein that controls muscle development.

There are nine known mutations of this gene, each controlling, to a varying extent, the development of muscles leading to excessive muscle development. Some are breed specific and others affect more than one breed. The three commonest mutations are F94L, nt821 and Q204X.

F94L is common in Limousin and several other breeds. It increases muscle fibre size with no associated increase in calving difficulty, lowered fertility or longevity. It can increase primal cut weights by up to 19%, with better feed conversion ratios. The meat typically has higher rates of tenderness, reduced fat and higher polyunsaturates.

Variant nt821 is a recessive gene which gives larger loin depths with a rounded rump and thighs. It also gives heavier birth weights and more difficult calving.

Animals carrying one copy of the gene and one copy of the ‘normal’ F94L will appear ‘normal’, that is no exaggerated muscling. These animals are known as carriers and can allow the recessive gene to pass through a couple of generations before causing any difficulty.

Variant Q204X is a partially dominant mutation of the gene. Cattle carrying one copy of it have larger loin depth, reduced fat cover and greater meat tenderness.

They also exhibit larger birth weights, increased calving difficulties and reduced milking ability in females. Again, carrier animals cannot be identified by their appearance.

What benefit is myostatin to producers?

Myostatin brings benefits of increased meat yield, better quality in terms of tenderness and reduced fat cover and high polyunsaturates.

F94L has delivered this for a very long time along with easy calving and milky cows. However this is the positive. There are significant negatives.

Can you tell the myostatin make up of an animal by your eye? No! Is it important? Yes!

Why is it important? You put a bull which is a carrier of a variant myostatin, to a cow which is also a carrier of a variant myostatin, and you will most certainly have calving difficulties and possibly caesarean sections.

Many bulls offered for sale today are carriers of variant myostatin. Why? Because without shape, bulls are not so easily sold.

Why is this happening? There are many cattle breeders, both pedigree and commercial, buying, and breeding by eye with no regard to the myostatins the animal carries.

I do not believe we can have an industry calling itself welfare friendly and sustainable when we are unknowingly or unwittingly breeding from cattle which we know, or should know, are carrying genes which will give problems sooner or later.

Variant myostatin is present in almost every breed. Yes, Q204X can even be found in Highlanders. Breeders pushing their breed down the route of more and more shape can inadvertently select for variant myostatin, unless they test for it.

The Scottish Government, in my opinion, missed a massive opportunity in not testing the whole breeding herd for variant myostatin and setting out an education programme on its use as part of the Beef Efficiency Scheme. The knowledge was available before it was devised.

I hear, from vets, of more and more difficult calving problems and more caesareans happening, and wonder how much longer can we allow this to continue?

When buying a bull, if you don’t know the myostatin make up of your herd, play safe with F94L/F94L. If you do know the myostatin make up of your herd and you understand what you are doing you can use variant myostatin to improve your returns.

The industry desperately needs knowledge of what it is working with and advice and education on how to manage variant myostatin. The alternative is at the worst a shrinking industry, at best possible government or retailer intervention to protect animal welfare.