30th July 2013

Forth Monitor Farm Focuses on Fluke Challenge

The family which runs the Forth monitor farm are fighting back against the causes of disappointing returns from their cattle and sheep, with fluke their main target.

The 815 acre (330 ha) Arnprior Farm, 12 miles west of Stirling, farmed by Duncan McEwen and his son also Duncan, is one of the network of Quality Meat Scotland (QMS) monitor farms throughout Scotland.

The McEwens’ lambing and calving percentages for 2013 are down on recent years, as is the case on many Scottish livestock farms.

The 550 ewes scanned lower than previous years at 178%, with the final lambing figure just over 150%, a fall of more than 10% compared to 2012. “The bad weather at lambing time didn’t help,” said Duncan McEwen junior. “But we also lost some lambs with pneumonia, and the results of post mortem by SAC at Perth, showed that the pneumonia had been caused by them having received poor quality colostrum, which was due to the ewes having been challenged by liver fluke.”

However the performance of the suckler herd has been the McEwens biggest disappointment. “When we scanned the 64 cows in early January, 14 of them were empty,” explained Mr McEwen (junior).

“The empty cows ranged in age from four to eight. The scanner confirmed their ovaries were fine, yet none of them had been seen bulling since housing on 6th October.”

There was better news with the first calvers, bulled in summer 2012. All have produced a second calf this year.

“We’re convinced fluke, which hadn’t been a significant problem on the farm until 2011, is at the base of most fertility issues and is undermining everything we do with the livestock,” commented Duncan McEwen (senior).

The in-calf cows turned out in the third week of May, have recently escalated the McEwens fluke concerns. They had been treated for fluke ten weeks after housing, with Ivermectin and Clorsulon.

“At the May monitor farm meeting the cows had just been turned out. We were advised to dung sample them,” said Mr McEwen junior. “This was straightforward to do. I walked up to several cows, fleshy and leaner ones, waited for them to stand and dung then, using a garden trowel and ice cream tub, collected a sample from each pat.

“The dung sample results shocked us – the cows were positive for both adult liver and rumen fluke. This was a double concern – firstly we hadn’t realised that rumen fluke was on the farm and secondly, the treatment the cows received ten weeks after housing should have taken out everything other than the rumen fluke.”

To ensure the cows received the correct amount of flukicide, the McEwens had individually weighed each animal and then drawn the correct amount of drug for the weight of the animal, into the syringe.

“I spoke to a vet at the earliest opportunity to try to establish how these cows could have mature liver fluke in them, explained Mr McEwen. “The vet suggested some immature liver flukes may have been in the systems of the cows when they were treated.

“Also, the morning after they were dosed, some of the cows were clearly subdued. The vet explained that when there is a heavy liver fluke infestation, some of the mature fluke killed by the treatment, can lodge in the bile duct.”

After receiving the dung sample results, the McEwens treated the cows with Levamisole and Oxyclozanide.

Dr Philip Skuce, a senior Research Scientist at the Moredun Research Institute, has spoken at a number of monitor farms on the subject of fluke. He has explained that rumen fluke treatment options are extremely limited. He said: “Oxyclozanide is the only effective treatment for rumen fluke, however, the presence of rumen fluke alone in the absence of clinical signs should not be taken as an indication to blanket treat the whole herd/flock.”

“Rumen fluke is a new challenge, and we’re concerned as to how much impact it has, particularly in a beast already infected with liver fluke,” said Mr McEwen. “We will continue to monitor the cows closely, particularly as there is only one product to control rumen fluke, so it’s crucial that it’s administered correctly and used prudently.

“It’s vital that we know our enemy. And the only way we will know what and where our enemy is, is by testing. In hindsight, we obviously wish we had tested the in-calf cows well before turn out.

“On our farm, in less than two years, fluke has gone from a routinely controlled parasite to just about the most important health issue in all our livestock. It seems that many other farmers are in the same situation. We clearly need to be more pro-active, look out for signals, test more often, respond promptly to results, and wherever possible alternate products, to help avoid developing flukicide resistance.”

The date of the next Forth monitor farm meeting has been provisionally scheduled for 8th October.

For further information, please contact the facilitator:

Stephen Whiteford. Email: stephen.whiteford@sac.co.uk, telephone: 01786 450964.

For general information on monitor farms, plus detailed reports of meetings: www.qmscotland.co.uk/monitorfarms

Photo caption: Duncan McEwen junior

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