Maximising lamb growth rates post-weaning should be a priority for sheep farmers, given the positive impact that earlier finishing can have on overall flock performance.
So advises Rumenco Technical Services Manager Dr Alison Bond, who points to a number of key management factors that will help to ensure as many lambs as possible are away before the next tupping season.
“Minimal stress at weaning is the first important step,” she says, “and this should be followed by optimum nutrition throughout, with specifically formulated feed blocks used to complement grazing, and then close and ongoing health monitoring to avoid any growth checks due to parasites, for example.
“Attention in these areas will keep weaned lambs growing, enabling target weights to be achieved in good time.
“A good aim is to have at least 70% of lambs away before tupping. This is not only beneficial for cashflow, but it will ease the pressure on grazing across the farm, making more forage available to ensure ewes are in optimum condition.
Dr Bond advises weaning lambs at between 12 and 16 weeks of age, to give ewes ample time to recover condition before tupping.
“It’s better to avoid the temptation to carry out any other tasks at weaning time, such as vaccinations or worming, as this will only add to the stress,” she adds. “If possible, return the lambs to the field they were in before weaning, ensuring that this is well away from the ewes. If the lambs can’t hear or see the ewes, it will make the process less stressful and ultimately keep them growing at a good rate.”
Ideally, lambs should be moved to good quality grazing withing a few days, with suitable supplementation then being a key consideration.
“In order to maintain health and maximise growth rates, it’s better not to rely solely on forage, as this may well be lacking in some of the important minerals, vitamins and trace elements.
“A ‘little and often’ approach using feed blocks is a better alternative than daily trough feeding, as it is less labour intensive and, being free access, is a more natural method for growing lambs.
“The formulation is important, however, to ensure the right balance of protein and energy to maximise growth rates alongside key ingredients to maintain health and vitality through these important weeks.”
Dr Bond recommends Rumenco’s Quality Lamb high energy and protein feed and mineral block, which has been formulated specifically for growing and finishing lambs on grazed grass, other forages or root crops. It is available in a convenient 14 inch, 22.5kg block, suitable for use indoors or out in the field.
“As with all Rumenco feed products, the Quality Lamb block has been independently trialled,” she says. “It has been shown to double daily liveweight gains in weaned lambs, when compared with feeding grazed grass alone, which in many cases will allow access to the higher value markets.
“Quality Lamb has also been trialled with lambs on stubble turnips, with this work indicating a 38-day shortening of the period to market when the blocks are fed, with improved carcase grades too.”
Alongside good levels of energy and high all-natural protein content to provide digestible undegraded protein (DUP), Quality Lamb blocks are fortified with all the essential minerals and vitamins needed to maintain health.
The blocks are also formulated for optimum rumen function, with the inclusion of the fermented yeast culture Celmanax. This consists of refined functional carbohydrates (RFCs) that are biologically active prebiotics and postbiotics, which deliver a host of gut health benefits that give lambs significantly improved feed conversion efficiency.
“Including a fermented yeast culture of this kind helps to stabilise the rumen environment, improving dry matter and protein digestion, and boosting intakes,” explains Dr Bond. “Again, we have good trial data to support this inclusion, with work showing a nine day reduction in the period to finishing in lambs receiving Celmanax in their creep feed at 5g/head/day, compared with those receiving a standard creep feed as a control. The feed cost savings alone, in this trial, led to a significant return on investment, whilst it is also worth considering the reduction in methane emissions resulting from a shorter finishing period for lambs.”
Dr Bond says sheep farmers should also be mindful of potential worm burdens in finishing lambs, adding that faecal egg counting should be used to monitor any threat.
“The aim should be to have as many lambs away as quickly as possible, and good nutrition is the key,” she concludes. “Management to avoid any growth checks, such as gut worms or any other challenges, is nevertheless important, to avoid undoing all the benefits delivered by quality forage and well-formulated supplementation.”
