Inconsistency in the faeces of a select number of cows was a concern for farmer Neil Brough and Alltech north region sales manager Bob Kendal. But analysis quickly identified the issue and the best intervention methods, which saw cell counts drop and butterfat increase in a matter of weeks.

Mr Brough farms 350 milking cows at Buckabank Farm, near Dalston in Cumbria. Having noticed inconsistencies in cow manure, Mr Brough sought advice from Mr Kendal to help identify if there was a wider issue with the ration or rumen function that needed to be addressed.

“On visiting the farm, it was noticeable that some — but not all — the cows were loose,” says Mr Kendal. “Neil said this was quite common, with cows recovering within a few days, and then others in the herd displaying similar symptoms the next day.”

Mycotoxin issues

Mr Kendal explains that this inconsistency was indicative of cattle being exposed to mycotoxin contamination. “It’s a risk that can often originate from mycotoxins being brought into the silage clamp at harvest, and that’s compounded by a storage environment which allows moulds and fungi to grow and proliferate. 

“It’s these often overlooked areas of feed management that can have a significant impact on overall feed efficiency - and ultimately the bottom line,” suggests Mr Kendal.

Testing the cows’ TMR To evaluate if this was the issue, Mr. Kendal carried out an Alltech 37+ mycotoxin analysis - a broad spectrum test for mycotoxins - to confirm if, and which, types of mycotoxin were present. 

“For accurate results, we took a sample of the TMR from the trough, so we could be sure that we were testing exactly what the cows were eating. The sample was then sent to the lab to be processed.”

Mr Kendal explains that these tests show the level of each mycotoxin within the samples provided. They give insight into how the mycotoxins could impair performance based on how the types that are present interact with each other - called the ‘Risk Equivalent Quantity’ (REQ).

“Some mycotoxins will affect somatic cell counts and milk yield. Others can be broken down naturally by rumen bacteria and, as long as the rumen is functioning normally, these types are less of a concern and won’t affect the cow too much in terms of feed conversion efficiency.”

The test for Buckabank Farm, however, identified a high presence of Penicillium mycotoxins, at 201 parts per billion. “Penicillium mycotoxins have the capability to kill the bacteria that are naturally present in the rumen, preventing them from being able to break down other potentially harmful toxins. This means that there can then be a whole range of mycotoxins affecting the cow and a compromised immune response. 

“In this instance, the presence of Penicillium mycotoxins had caused disruption to the entire function of the gut, which is why we were seeing loose dung. If left untreated, this could have had a detrimental impact on milk yields and, ultimately, the bottom line at Buckabank.”

Control measures

Following the test results, Mr Kendal recommended introducing a mycotoxin binder into the TMR. This would reduce the impact of the Penicillium mycotoxins on herd health and performance, while also aiming to improve feed efficiency.

“I suggested Mycosorb A+ because it has a broad absorption profile and superior binding capabilities, including the ability to bind to Penicillium mycotoxins, and was a good fit with the existing ration.

“For quick results, I recommended using a double dose forthe first couple of weeks, then reducing to a standard rate of 50g per head per day. The mycotoxin binder was added daily into the mixer wagon to ensure a uniform mix within the TMR.

“Within two weeks, we were observing improvements. Far fewer cows were producing loose dung on a day-to-day basis.”

Mr Kendal explains that milk yields were maintained despite cows heading towards the end of their lactation cycle. Cell counts reduced from 168 to 106, and butterfat increased slightly from 4.16 to 4.25% due to efficient fibre digestion improving milk quality.

Mycotoxins have been proven to contribute significantly towards poor feed efficiency in dairy herds.

FCE financial opportunities

A recent Alltech pilot study revealed that poor feed conversion efficiency (FCE) is responsible for losses averaging £113/cow/annum. “Multiply this across a 200-cow herd, and losses from poor FCE are typically costing £22,600 each year,” says Mr Kendal.

“FCE can be affected by other environmental factors that compromise cow comfort, such as lighting or housing set-up, water intake and feed factors like forage quality. But the presence of mycotoxins in feed is an important risk that can be easily resolved as demonstrated at Buckabank Farm.

“For anybody concerned about the impact of mycotoxins on their herd, I’d recommend testing in the first instance, to find out if and what mycotoxins are present.

Once you know what you’re dealing with, it’s then possible to identify the most appropriate action to minimise the effects on your animals,” says Mr Kendal.

Alltech Navigate initiates changes

Mr Brough has seen some good results in terms of improved feed efficiency and reduced waste within the last few months - over and above the addition of a mycotoxin binder.

“Last year, we had an Alltech Navigate assessment, which saw an adviser come out on farm and look at how we make and store silage.

It also included an assessment of the feeding system and our housing, to build a picture of where losses may have been occurring and to offer recommendations on areas that could be improved,” he says.

“It was a useful exercise. Following the visit, we switched silage inoculant and started using a compactor during the ensiling process to help avoid storage losses.

“Since then we’ve seen improved silage stability, reduced slippage and waste, which is a real improvement,” concludes Mr Brough.

Buckabank Farm Facts:

• 220ha dairy farm in Dalston, Cumbria

• Indoor system

• 350 milking cows, with 350 followers

• TMR includes grass silage, maize silage, caustic wheat,

• soya, maize meal, butterfat extra, minerals and mycotoxin binder

• Rolling average yield 11,000 litres/cow, 4.22% butterfat and 3.36% protein.

Download your in-parlour poster on the 9 warning signs of mycotoxins in your dairy herd

CREDIT: British Dairying October 2020