Selecting the most suitable lambs for slaughter

Offaly Lamb Producer Group, in conjunction with Irish Country Meats (ICM), recently held a lamb selection event focused on drafting lambs for slaughter.

The event included on-farm sessions on Ken Matthews’ farm in Killeigh, Offaly, and in Gurteen Agricultural College, giving hands-on advice on how to best handle lambs for optimum selection pre-slaughter, followed by a factory visit to assess how lambs performed (grade, fat cover, etc) once slaughtered.

Steve Powdrill, a beef and lamb specialist with EBLEX, ran the on-farm lamb selection demonstration and the follow-up factory event.

With over 30 years of experience in the meat and livestock industry, Steve has developed a wealth of knowledge in beef and lamb selection and carcase classification and is charge of the EBLEX live-to-dead events.

Currently, there are about 32 abattoirs in England linked to the programme. Steve explained that the events quickly gained traction with the combination of the on-farm selection and the factory event helping to develop the full picture and show participants how issues such as over- or under-fleshed animals, overweight or varying conformation grades affect the suitability of carcases for different market specifications.

The live-to-dead events and getting animals ready for slaughter are a central part of EBLEX’s Better Returns Programme, which aims to improve farm profitability.

Market requirements

Steve said that a big aspect of farm profitability is maximising returns from the market. He said that this can only be achieved by knowing and producing what the market requires.

“Farmers sometimes tend to produce a product and then try to find a market. The Single Farm Payment is reducing, so it is now even more important that you assess your system and see if you are heading in the right direction.

“My advice to farmers is always to first identify what is the best system for your farm and how to produce to a specification in the most efficient manner.”

He said that finding the best system often gets sidetracked into discussions or arguments on breed choice – he feels this can be a distraction from the task of finding the best farming system for you and your farm.

“I believe there is no best or worst breed. Breed choice should take into account what best suits your system and gets animals to the end market in an efficient manner, consistently.

“I often see an emphasis in pedigree breeding on selection on the head and feet, yet these are the first things that come off and go into the skip.

“You have to make the decision if you want to produce one really good lamb with a U/E grade or if you are better off focusing on fertility and getting two R3s.”

Meat producer

Steve said that commercial livestock farmers should see themselves as meat producers rather than animal producers.

“A big ass or extreme conformation is a poor measurement of meat quality. Consumers want taste, tenderness, texture and, above all, consistency.

“Breed can have a small influence on this, but delivering quality for consumers consistently starts with you and the way you select your animals for slaughter.”

Steve used four varying carcase classifications as examples of what different markets require or, equally important, do not require.

Starting at the lower end of the conformation and fat scale, traditionally there was a relatively good market for lowly fleshed O1 grading carcases in the UK for manufacturing meat for ethnic markets (kebabs or curries, for example).

He said that this market is reducing with an increase in buyer affluence and taste preference moving to higher-quality meat cuts and better-fleshed carcases.

Lamb classification in the UK differs to Ireland, with fat classes 3 and 4 split into low and high.

Lambs with R3L carcases, weights 18-21.5kg, suit over 85% of the marketplace and will deliver a consistent product to consumers.

Steve then discussed a U3H carcase, heavier in weight, 22kg to 26kg, often associated with local butchers or food service, but these only account for 8-10% of the industry.

The last classification discussed was carcases with fat cover 4 and 5. Irrespective of conformation grade, Steve said there is no market that wants to accept these carcases.

He said that bringing carcases to this grade is adding unnecessary cost to farmers and processors.

“The heavier we go on carcase, the fatter we generally go. There is a market for everything, but at a price. Lamb fat is a huge turn-off for the consumer and they will inevitably go for chicken. As red meat producers, that is the last thing you want happening.”

Optimum selection

Physically handling animals is central to optimal lamb selection, according to Steve.

“I don’t know anyone who can spot the differences accurately in animals with a sheep skin rug on their back – you need to get in among sheep and handle lambs. It’s easy to see the differences in a hanging carcase, but by that stage, it’s too late.”

The conformation class scale in operation in Ireland and the UK is E, U, R, O and P, where E is the fullest conformation class and P the weakest. Some continental markets also have an S class for lambs with extreme conformation.

The three areas for assessing conformation are the leg, shoulder and loin, with Steve explaining that two out of these three areas will generally make up the conformation.

Breed generally dictates leg shape, with E and U grades possessing convex, curved legs with more muscle.

Generally, R grades have a straight to slightly curved appearance, while the leg shape in O or P grading carcases is concave or falling inwards.

In hanging carcases, the difference in shape between the best and lowest conformation can be described as a U shape in an E and U grade and a V shape in an O and P grade.

Steve said that, for him, the loin is the key area to look for in a sheep, with a long loin adding more value to lambs due to higher-value meat cuts (lamb chops).

He said the best way to assess the loin is to put your open hand along the top of the loin. If your hand is supported flat, the conformation is likely to be R/U, while if your hand starts to fall away on your fingers and thumb, it is more than likely an O grade, with a severe falling away denoting a P grade.

The tips of the spinous processes can also be used to give a good indication of fat cover. If it is hard to feel the individual tips when running your hand along them, then the animal is generally ready to go.

On the other hand, if it is easy to feel the spinous process or your fingers fall between them easily, then animals are generally short of fat cover.

The other areas to assess fat cover on are the tail dock, ribs and brisket. Steve said the tail is usually the first place animals start to put on fat.

If all the joints on the tail can be easily felt, then the animal is short of finish. If there is a nice covering of fat on all the joints and its beginning to have some width at the tail root, then it is a sign the animal is ready. However, if you cannot feel the joints and the tail is wide and deep, the animal is more than likely too fat.

On ribs, if you run your fingers across the ribs of the animal and can easily identify individual ribs without any real pressure, then an animal is likely to be under-fat.

If the ribs are distinguishable with a cover of fat over them, lambs are in prime fat cover, while if it is hard to distinguish individual ribs even with pressure, the animal is likely to be over-fat.

The brisket is another place to determine fat cover, although it is not commonly used. If you turn an animal over and there is a fold of fat developing on his brisket, it is a sign that animals are getting fat and can be drafted for slaughter.

Draft when fit

The advice is to draft animals on fat cover and not to allow animals to go over-fat in the hope of gaining extra weight. Steve said that animals on good grass will go from fat class 3L to 3H in 10 days to two weeks or often far quicker in the prime grazing season.

“By chasing weight you run the risk of being out of specification for fat and also on a deadweight basis exceeding the maximum payable weight. Both of these cost money. In fact, producing fat takes almost four times the feed energy to put on when compared to muscle.”

He cautions against incorrect handling techniques, highlighting carcase bruising as a significant contributor to devaluing carcases. Animals should never be caught by the wool, especially in the loin area, with the correct technique to handle lambs with one hand under the animal’s head and the other under the back leg area.