Beef farmer quits silage making and sees growth rates rise

Inconsistent weather led Aberdeenshire-based beef farmer Murdoch Duncan to stop making silage in favour of feeding calves a cereal diet.

Mr Duncan, who runs the 650ha East Lediken farm in partnership with his father William and mother Isobel, previously fed the Charolais-cross calves from his 300-cow herd silage, and a 60% barley, 40% mineralised blend ration (16% protein growing mix).

But he says it was a complex system and the silage quality was not good enough to maximise the growth potential of the continental breeds.

“No one can tell you at the start of the year whether a silage crop will be good or not because of the weather.

© Charlie Fraser Hopewell

“It was difficult to achieve consistent growth rates so it would take longer to get them to a target weight for the store market, making it harder to plan,” says Mr Duncan.

See also: Using beta maize as a feed replacement saves farmer £120/head

“There was a single silage cut each year aiming for bulk, which meant the protein levels were lower, so it wasn’t powerful enough for the calves.”

Growth rates and the diet

Calf growth rates were variable on the silage diet and averaged less than 1kg/day.

It was taking up to 16 months for calves to reach the 500kg target sale weight, so they were not sold off the farm until July.

“We wanted to simplify the system and get calves away faster,” says Mr Duncan.

The nutritionists used a combination of urea and a feed enhancer on the barley to improve its nutritional value, while the barley straw was treated with ammonia.

The calves had access to the treated straw at grass with their mothers. Then in late summer a 20% protein ration was provided.

The calves were gradually weaned off and put on to the treated barley with mineral balancer pellets and ammonia-treated straw for roughage.

“We decided to introduce the 20% blend formulated in September while the calves were suckling their mothers.

“Treated straw was also introduced for the cows at the same time. The blend was slowly mixed with the treated barley over the next couple of months until the ration was 60% treated barley, 40% blend. At this time the calves were also eating the treated straw.

“We spoke with the nutritionists at Harbro to see if carrying on with this system when weaned would be OK as this would reduce stress at housing.

“We were advised to carry on with the 60% treated barley, 40% blend mix, until the calves had been housed for at least four weeks before we started blending the mix to remove all the blend and end up with a 16.5% high-protein mix made up of treated barley and a mineralised balancer pellet.”

Growth rates took off, and Mr Duncan says they quickly saw a dramatic increase in growth on the enhanced grain, with calves averaging liveweight gains of 1.8kg/day.

Harbro ruminant specialist John Smith says the impressive growth rates have been achieved by getting extremely high barley dry matter intakes of 11kg/day.

Feeding that level of barley in a diet would normally compromise rumen health and lead to acidosis and bloat.

“To overcome the risk of acidosis, we treat the grain with urea and our own product, called Maxammon,” he says.

The product can be used on any grain to make it alkaline. It breaks down the grain structure in a chemical reaction known as ammonification, which lifts the pH from a slightly acid pH 6.5 to an alkaline pH 9.

“It is this change that is the key because a more alkaline rumen allows us to feed the exceptionally high dry matter intakes of grain safely, with a much reduced risk of acidosis,” Mr Smith explains.

“Now we are getting calves away as early as eight months old at 500kg. The average age is about 10 months and everything is gone by 14 months,” he says.

One animal reached 576kg in less than 12 months and made £1,280 on what Mr Duncan describes as a “relatively poor finishing market”.

Huge cost saving

Costs have been saved, too, because it has helped streamline the beef enterprise.

“The cost saving is huge. We are getting the same prices for the calves but it is up to six months earlier.

“That’s six months we don’t have all the cost of keeping them and it also frees up more grazing for our cows.

“By the time calving ends in May, the previous year’s stock has been sold on,” he says.

The cows, too, will be switched to the ammonia-treated, straw-based diet this year so only a small acreage of haylage will be made for the bulls and sheep on the farm.

“It will take more pressure off the farm in the late spring,” says Mr Duncan.

Harbro nutritionist Peter Oag says the calves are getting a reputation for being fast-growing even after they are sold.

“The growth rates are being maintained even after they have been sold on to finishers because of their improved rumen health,” says Mr Oag.