As September approaches, attention will be turning to winter rations and this year is expected to see a heavier reliance on home-grown feeds.
Ruminant product manager with ForFarmers Nick Berni says: “Cereal prices are lower so we are sure to see more being used on the farm, and although this comes with its benefits, there are pitfalls to guard against too.”
A particular concern when there is a heavy reliance on rolled cereals is the level of starch being fed and as starch levels rise, so does the risk of acidosis.
“This may only occur at a sub-clinical level but it will always impact performance, and when it becomes severe, there will be damage occurring to the lining of the rumen,” he warns.
The live yeast product, Levucell, has been designed to help in this situation, as it can regulate rumen pH, improve fibre digestion and scavenge oxygen, all of which have a positive effect on rumen health.
“The product has many modes of action,” says Mr Berni. “By utilising oxygen for example, it helps create the ideal environment for the rumen’s anaerobic microflora which, in turn, gets other important processes under way.”
This includes the ‘mopping up’ of lactic acid by the bacteria encouraged by the yeast which will help to maintain a constant rumen pH of 6.2 or higher.
“This is a particularly important benefit in high starch diets such as those including barley, wheat or maize,” he says.
The product also works on the fibre in the ration, particularly breaking down the indigestible component, making more of the feed’s energy available to the animal.
“Once the digestible fractions of the fibre [the cellulose and hemicellulose] are released, the yeast also helps in the digestion of these components,” says Mr Berni. “It does this by stimulating the bacteria that break down hemicellulose and cellulose, so they can be utilised by the animal.”
An important characteristic of Levucell is its encapsulation which protects it in challenging conditions.
“This could mean protection from high temperatures which can be used in the manufacture of cattle or sheep compound feeds, or protection from the antimicrobial actions of minerals which could be used in a pre-mix,” he says.
This protection allows it to be incorporated into compounds, blends and pre-mixes and to be easily used in home-mixing and in total mixed rations, he says. There, it remains intact and alive, and ready to do its work once consumed by the animal.
“Live yeast can be used from weaning to slaughter and in some situations this may be the best option. However, there’s no absolute right or wrong, and the decision will depend on the system, breed and diet type used.
“A high proportion of the beef feed we sell now includes Levucell,” says Mr Berni. “And since improvements in daily liveweight gain of 10-12 per cent can reasonably be expected, it is easy to account for its growing popularity.”
Northumberland beef and sheep producer, Stephen Trobe, has never been one for complicated rations nor a high reliance on by-products, having experienced the pitfalls in his stock in the past when something goes seriously wrong.
“At one point we lost six fat cattle in a week,” he says, describing the time when he inadvertently allowed the starch in the finishing diet to climb too high.
Today, he keeps a closer watch on his ration’s formulation and always ensures starch does not exceed 40 per cent, although he is conscious he needs to keep pushing cattle forward to finish on time and to meet target grades.
Farming at Ogle Dene Farm, Whalton, near Morpeth, most of the progeny from his 135 Limousin and Charolais suckler cows are finished on-farm, generally selling to Linden Foods’ nearby abattoir, achieving 80 per cent U grades and averaging a score of three for fat.
Sired by either a Limousin, Charolais or British Blue bull – or AI’d to Angus if heifers – the cattle will generally be ready for sale at around 20 months, at deadweights of 300-320kg for heifers and 370-380kg for castrated bulls.
With the system running smoothly after the earlier hiccup, Mr Trobe says he was initially resistant to trying a feed additive in the ration when the idea was suggested by his feed supplier, John Telfer from For Farmers.
Mr Trobe says: “John wanted us to try Levucell. But I wasn’t keen to bring additives into the ration as I still have bitter memories of losing the cattle to acidosis when we over-used a by-product and got the balance wrong.
“I told him I did not want to alter the ration in any way and certainly didn’t want to increase the starch.”
Slightly reluctantly agreeing to undertake a small farm trial in February to March, 2015, a batch of heifers – which were born in either spring or autumn and reared in one group from around eight months of age – were randomly split into two groups.
“We randomly allocated the heifers to one of two groups, with around 20 in each group,” says Mr Trobe. “We weighed them all in, kept them on the same ration, and treated the groups in exactly the same way except for the Levucell which was top dressed over the feed of one of the groups.”
The total mixed ration which was fed at the time comprised straw, bale silage, rolled cereals, biscuit meal and a For Farmers beef grower nut with additional minerals. Fed ad-lib, it analysed overall at 38 per cent starch and 13.5 per cent crude protein.
The cattle in the treatment group received 80g/head/day of Levucell while the control group had none.
“We ran the trial for just 40 days and I have to say the results were quite remarkable,” says Mr Trobe. “You could see a difference in the stock soon after we started the trial although I hadn’t really expected to see any difference in weight in such a short space of time.”
In fact, the group fed Levucell, which weighed from as little as 250kg at the start of the trial, achieved an extra 0.25kg/head daily liveweight gain compared with the control.
Over the 40 days of the trial, this represented 10kg extra gain per head, worth around £20 per animal.
“As soon as the trial was complete, we had to assess whether to stay on the product,” says Mr Trobe. “It wasn’t cheap so we did the sums but the case was overwhelming.”
Over the 40 days of the trial, this amounted to £2.24/head, leaving an extra margin after the £20 extra gain of £17.76 per animal.
Today cattle at Ogle Dene Farm are routinely fed the product in their total mixed ration, and the benefits are said to be clear.
“When they come in off the grass in autumn, the risk of acidosis is huge,” says Mr Trobe. “Of course I will still keep a tight eye on them but so far I haven’t lost anything since we started on the product.
“I believe it helps them digest their food and it definitely helps us reach our targets earlier,” he says. “This clearly improves profitability as when the cattle get up towards 400kg they consume vast amounts of feed each day, so the sooner they go away, the more it helps with our margins.”