Egg count can cut need for drenches

Monitoring FEC samples this year has saved a Welsh sheep farming partnership the cost of drenching more than 1000 lambs, which is a significant sum of money.

By closely watching FEC levels, the Davies family, who run 5000 Welsh Mountain ewes, were able to delay the first routine drench by three weeks until the first worm eggs were seen.

They continued to keep a regular check on egg counts and were also able to delay the second drench.

By drenching only when necessary throughout summer they saved between one and two drenches across the flock and this year drew 980 lambs at the beginning of the season and sold them drench-free.

Llinos Davies, who farms with her husband, Berian, and his family, says reducing the frequency of drenching has helped safeguard against a build-up of roundworm drug resistance, in addition to saving money.

Labour, she calculates, has been the biggest cost saving because the stock is not handled as frequently.

“There have also been cost benefits from the money we have saved on the drench itself.”

The new system is very different to the one they previously practiced at Eisteddfa Fawr Farm on the Preseli Hills in Pembrokeshire.

The normal practice was to routinely drench all lambs every three to four weeks.

They decided to have a go at monitoring the flock after attending a demonstration day organised by the Welsh farming support body, Farming Connect.

During that session they learnt about the life cycle of parasites and this helped them understand why they needed to monitor at particular times.

They began using a system of parasite assessment.

“It was a little bit fiddly to start with, but as I became more confident it became much easier,” says Mrs Davies.

Fortunately, she didn’t have to go to the expense of buying her own on-farm FEC kit because she had access to a shared kit provided by Farming Connect.

The kit is stored at a neighbouring demonstration farm and is available whenever she needs to use it.

In the past, store lambs were drenched an average of three times between birth and sale from mid-August.

This involved time spent gathering and dosing, which increased the workload on the farm and put stress on the flock.

Treated

Now they are treated only when egg counts exceed a certain limit.

“When the count is between 300 and 600 eggs/g we can leave it a week or so depending on the situation.

But when the reading is 600 or more we need to go in straight away with a dose,” says Mrs Davies.

The Davies’ were prompted to monitor faecal egg counts after noticing a rise in nematodirus infection in spring.

This parasite is often fatal in lambs, so it was important economically to control it.

“When we counted too many of those eggs we drenched lambs,” Mrs Davies explains.

“With some types of parasite it might be possible to delay the dose for a week, but with nematodirus it is important to deal with it immediately.”

As the nematodirus parasite dies off in July the flock can become infected with the strongyle parasite.

The FEC kit distinguishes between both types of eggs.

The FEC samples need to be taken from a group of lambs.

When there are 200 in the group, 10 different scoops are necessary.

“It’s easier to do as lambs are weaned because there are no ewes in the group to interfere with the sample’s accuracy,” she says.

Mrs Davies relies on the accuracy of her own readings, but next season plans to check the samples occasionally by comparing the results with tests carried out by a professional lab.

“We will check samples every now and then just to make certain we are getting the correct readings.”

fwlivestock@rbi.co.uk