Pregnancy scanning is key to maximising profits

Scanning to improve feed efficiency is going to be key to maximise weight gain and profits next season.

Liz Genever, sheep and beef scientist for EBLEX, says sheep enterprises are likely to be put under increasing pressure during the next 12 months, with lamb prices unlikely to rise to levels seen last year.

This is largely due to uncertainty over the relative currency value in Europe and poor economic conditions in some customer countries.

Meanwhile, feed prices have risen considerably. But she says producers can still make good money by maximising the number of kilos they produce next season by feeding ewes accordingly ahead of lambing.

“We know forage quality is variable and concentrate prices are high. If that isn’t a motivating factor to scan, I don’t know what is,” says Dr Genever.

“We need to save as much feed as possible, which means knowing feed requirements for those sheep,” she adds.

Dr Genever says not scanning could result in the difference between profit and loss in a year like this. “Lambing time is when you are going to make your money and not feeding appropriately will affect income considerably.”

Feeding appropriately

Dr Genever estimates that a flock of 400, scanning at 181%, will need to be fed approximately 3,833kg of silage at a cost of £1,150. This figure is calculated on 271 twins beings fed 11.2kg of silage over 28 days, 90 singles being fed 0.2kg for 14 days and 30 triplets being fed a total of 18.2kg for 42 days (see table 1). But not scanning and feeding all 400 ewes for twins at an additional 647kg will cost an extra £194.

This saving alone would pay for scanning at a cost of £180 – the equivalent of approximately 45p a head.

“Scanning offers a real price benefit by giving the producer an understanding of what sheep are carrying and, therefore, what their requirements will be. This year in particular, when feed is £300/t, any saving you can make will useful.

“It ensures that if there are triplets, they are being fed appropriately, which reduces ewe and lamb mortality.”

Dr Genever calculates that a 5% increase in lamb losses between scanning and lambing due to incorrect feeding equates to a gross margin loss of £5 a ewe at flock level. In a flock of 400 ewes this equals £100.

Meanwhile, an increased ewe replacement rate of 20-25% results in an additional fall in gross margin of £5.50 a ewe, including replacement costs.

“If both losses and replacement rate are increased by 5% there is a £10.10 reduction a ewe in gross margin, so the average cost of scanning at 45-55p starts to makes sense.”

Business performance

Sheep producer Ed Higgins, of Frodesley Park Farm, Shrewsbury, says pregnancy scanning is a critical tool for analysing his business performance.

“It is a really good performance indictor. Scanning acts as the first point of performance monitoring for our flock.”

Mr Higgins lambs 1,250 Suffolk mules in three groups from February to April. He scans the first batch of sheep to lamb in early December.

From the scanning results Mr Higgins assesses mortality rates before and after turnout and the number of lambs sold. Using the results, he then assess where the problems may have occurred and is able to make key changes to improve his lamb output.

“It is very good to know what your mortality is, so if you start off with a low scanning percentage, you should, in theory, have a low mortality percentage,” he adds.

For instance, Mr Higgins explains that if his scanning is about 185% he expects his mortality to be lower at 12%, but if scanning percentage rises to 200%, mortality creeps up to 15%.

This, he says, is traditionally down to the fact that ewes are carrying a higher number of triplets.

“If we know we are going to have a high number of ewes expecting triplets we can plan ahead and get extra help in during lambing, because they will need more TLC.”

Scanning also helps him to streamline feeding and sell unproductive stock.

“The main advantage is it enables us to find empty ewes and we can get rid of them at a time when there isn’t a lot of cull ewes on the market.”

This means barren ewes are passengers for the season and elevate pressure on housing and feeding, as well as acting as an additional income stream while the market is still buoyant.

Scanning also means Mr Higgins can feed appropriately, which he says is more cost-effective than guessing ewes’ nutritional requirements.

Ewes are housed three weeks prior to lambing, where they are split up into groups of triplets, singles and doubles and fed appropriate rations. Before this they are fed hard feed at grass.

“There is about 0.2kg difference from a single to a twin, and a twin to a double as a rule of thumb,” he explains.

However, this is highly dependent of the forage quality, so Mr Higgins conducts silage analysis before formulating rations with his nutritionist.

“Feeding ewes correct amounts in the run-up to lambing means lamb birth weights are not too heavy or light and this prevents problems at lambing, because a single is a struggle to lamb if they’ve been overfed,” he says.

Kate Phillips, sheep consultant for ADAS, says producers looking to scan pregnant ewes should do so between 40 and 90 days.

She advises producers to get their forage analysed before formulating rations and to then seek advice on the right intake balance.

“In a perfect situation, we would have good-quality forage and a supplement to balance any deficiency, but we know this year forage is hugely variable, so it is very important to get it tested.”

She said ewes should ideally be fed additional energy in the run-up to lambing to help with lamb development. She says producers shouldn’t feed more than 0.5kg of feed a day a ewe. “Anything more would drop the rumen pH too much,” she explains.

But she warns any ewes in poor condition need to be isolated and fed immediately.

“If ewes are too small it will compromise milk yields and the thinner they are, the more susceptible they are to disease.”

She says farmers need to “get their hands on” ewes and check their body condition score.

A lowland ewe should have a body condition score (BCS) of 2-2.5 mid-pregnancy, while hill ewes need a slightly higher BCS of 3.

However, she says weight gain should be gradual, with farmers feeding no more than 0.2kg a ewe a day over a period of approximately four weeks.

“If you feed too much it all goes onto the lambs and you can’t get them out.”

More on this topic

Farmers Weekly has reported a high incidence of early lambing and calf losses. We need your help to build a UK-wide picture of what is happening on individual farms and what the cause could be. If losses are a problem in your flock or herd this year, let us know by filling in our short six-question survey online.

Rhian Price on G+