The number of lambs sold or retained for breeding is one of the most important factors affecting sheep flock profitability, so getting the most from all lambs produced is crucial.
And while there isn’t one area that determines the level of lamb mortality, adequate colostrum and effective management of surplus lambs are key areas for consideration, according to ADAS sheep consultant, Kate Phillips. She says lambs that die are more often than not likely to be surplus lambs (from triplets, or where an ewe has died).
“One of the main reasons for this is because surplus lambs being fostered or reared artificially often don’t receive enough colostrum, and a good feed either from its mother or a foster mother is vital,” she says.
Selecting surplus lambs
The method for rearing surplus lambs will vary from farm to farm, and fostering will often be the first option before opting to rear lambs artificially on milk replacer. However, irrespective of rearing technique, there are some basic methods that should be applied when identifying lambs to foster.
“When fostering lambs from triplets, it is always important to leave the ewe with a balanced pair that will compete equally for milk,” says Ms Phillips. “It’s important not to foster lambs that are sick or weak, or foster on to ewes with insufficient milk or those that are inexperienced.”
Rearing surplus lambs
And when debating which technique to use to rear surplus lambs, Ms Phillips recommends fostering on to ewes with single lambs (wet/cross fostering) as the first port of call. Planning and scanning ewes is vital when adopting this technique, she says.
“The ideal situation is always to leave lambs on the ewe, but when this isn’t possible then wet fostering is the next best in most cases.” In this situation Ms Phillips recommends grouping ewes carrying singles and triplets next to one another, making it easier to select which ewes to foster on to. “Having surplus lambs marked and close by also makes it easier for covering lambs in amniotic fluid from the foster ewe as soon as she has lambed and then presenting the surplus lamb as hers by placing it under her nose.”
The technique of skinning – taking the skin from a dead lamb and placing it on to a foster lamb – is also a foster technique that some farmers may use, although Ms Phillips says the results are varied and is time-consuming and messy.
Lamb adopters will also be used by some producers in order to get the lamb to bond with the ewe. However, Ms Phillips stresses that when using adopters the ewes must not be in them for more than 48 hours and should have access to plenty of food and water.
Artificially rearing surplus lambs
When any of the above techniques fail or when there is insufficient single-bearing ewes to foster on to, or simply the number of surplus lambs are too great, then artificially rearing lambs will be the next step, says Volac young animal technical specialist, Jessica Cooke.
“While artificially rearing lambs may seem like an expensive option, with current lamb prices it is cost-effective.”
She says if lambs were reared artificially from birth to 35kg on milk replacer and dried feed, you could be looking at profits of £20/lamb depending on the system. The technology available to help rear surplus lambs include a teat on a bottle, or more commonly a bucket with a heating element to maintain milk temperature after heating through, to fully automated systems that mix and maintain the temperature of the milk.
“The individual farm situation will determine what system of artificial rearing will suit best. When a farmer has a lot of surplus lambs an automated system may be the best option, as they can feed up to 70 lambs, and with a similar level of performance as that of a lamb reared from a milky ewe.
“Little labour is required for this sort of system and lambs will tend to achieve a higher growth rate than bottle-fed lambs.”
However, hygiene and attention to detail is critical when artificially rearing lambs, says Dr Cooke. “The concentration of milk substitute must be consistent and it’s essential to keep an eye on the machine calibration. It’s also important to keep on top of machine hygiene.”
CASE STUDYHuw Davies, Llandre Farm, west Carmarthenshire
An increase in lambing percentage from 175% in 2009 to 189% in the past year forced Welsh sheep producer Huw Davies to review the way he reared surplus lambs.
“In the past year when we scanned 85 ewes with triplets we realised we had to think of a new route to rearing surplus lambs, rather than the usual 30-40 we would normally rear by wet fostering or artificially using a bucket with heating element.”
Mr Davies had tried leaving some triplets on the ewe but found ewes were getting mastitis. And because most of his 620 Beulah x Mule flock lambed within a three-week period, he decided to explore the option of using an automated milking system.
Th past year was the first year he used an automatic system and got great results. Mr Davies says the management of the system was easy and lambs were left with ewes for the first 12 hours to ensure adequate colostrum intake. After 12 hours either smaller or bigger lambs were selected to be reared artificially, to leave the ewe with an equal pair. Selected lambs then spent one day in a nursery pen being taught how to suckle from the machine, which Mr Davies says only took about 20 minutes, before being moved to the main group. Lambs were then all marked with a date and weaned at six weeks old. Creep feed was introduced from day one.
And the success of artificially rearing surplus lambs was shown by the lack of losses. “Out of the 78 lambs we reared on the machine none of them died.” In fact, Mr Davies says after lambing in early March, the first lambs ready to be sold in early June were those reared on the automated milking machine.
“They did a lot better than lambs with ewes, as we had a tough spring. The first lambs in early June made 16kg/deadweight and all 78 were sold by the end of August.”
Although Mr Davies has not yet done the final costing, he believes the first lot of lambs paid for the £1800 worth of milk used in the machine – which was rented for £150 for six months – during that period. “We came out ahead of the game and the lamb losses were not there. It was a win-win situation.”
And with scanning results for this year at 193% with more multiples, Mr Davies says he will definitely be using the machine, even if lamb prices were to drop. “This system only took 10 minutes to manage each day, and the losses were not there. It was also more of a pleasure watching these pet lambs as they did so well,” he says.