Being a small holder or a hobby farmer is challenging work but can show tremendous benefits. 

As a small holder or a hobby farmer, you do have a responsibility to use wormers in the most efficient and cost-effective way, but how can you make sure you are using the correct product and even treating the right parasite?

From whom can I get advice?

SCOPS and COWS are two expert organisations who give excellent advice. Any farmer or livestock holder should regularly go to their website for lots of information and tips. 

On both the SCOPS and COWS website, there is a comprehensive list of products detailing which parasites they target, how to use them, what trace elements they cover and the meat withdrawal period. Your vet or pharmacist or the SQP at your local retailer should be able to advise too.

And we do strongly recommend you seek advice, if you’re not already up to speed on farm animal parasites and their control. Worms can cause significant loss of production, illness, and even death (especially in young stock), and resistance to wormers is a massive and growing issue. Worming cattle and sheep isn’t like dogs or cats as a result. Expert advice is easily available, so make sure you take advantage of it!

What is a Faecal Egg Count?

A faecal egg count (FEC) counts the number of worm eggs in faeces (dung). It is used to monitor the worm burden in sheep. The results are presented as ‘eggs per gram’ (epg) of faeces.

Who can do FECs?

You can use a suitably equipped and trained vet practice, a commercial service, or adopt a DIY approach. The faecal samples should be fresh when collected (less than one hour old) and kept cool (not frozen) in an airtight container or plastic bag, before examination or delivery to the laboratory within 48 hours. If the faeces are too old, some eggs will have hatched, and the reported egg count will be an underestimate.

What can a FEC do?

  • Help develop a more effective and sustainable worm control programme
  • Give a good indication of the level of adult egg-laying worms present in the animal
  • Provide an indicator of infection with the main gut worms
  • Identify eggs of Nematodirus worm species
  • Give a useful guide to the level of worm affecting the group
  • Be used to detect whether wormers are fully effective

Should the sheep or cows be healthy?

The sheep and cows who you are assessing the faecal egg count should be healthy and have had full access to pasture and/or feed before sampling, otherwise the FEC will be difficult to interpret. For this reason, FECs are used only for monitoring and not as a disease diagnostic aid.
If you have a cow or sheep who is looking unwell then it is vital that you seek veterinary assistance.
When parasitic gastro-enteritis (PGE) is suspected in cases where sheep are profoundly ill, a worm count as part of a post-mortem examination is a much more appropriate way to estimate worm burden.

What are the two types of sampling?

FEC sampling (1)

  • Each test must be based on at least ten individual samples.
  • Samples must be taken at random. Do not try to choose from the flock or herd.
  • Samples must be of fresh dung.

FEC sampling (2)

  • Flock or herd samples can be taken either by gathering the sheep or cows in the corner of a field for a few minutes, then picking up samples when they move.
  • OR carry pots/bags when out sheep and cattle herding and take a sample as they get up.

Interpreting results

Interpretation of an FEC is quite complex and depends on several factors, which you should discuss with your vet or adviser. The lab should also be able to provide a guide as to what is “High”, “Medium” or “Low”.

So why should small holders and hobby farmers be worried about anthelmintic resistance?

Wormer resistance is the loss of sensitivity to a drug in a worm population, which was previously sensitive to the drug. This resistance is passed on through generations of worms, as a genetic trait, so once it is on your farm it is there to stay.

It is important to note that it is not your livestock that have developed resistance, it is the parasites themselves.

Can FEC’s help with fighting resistance?

Parasitic worms are rapidly becoming resistant to the available treatments, so a control strategy based around usage of these worming products is not maintainable long term, and that also means many older management practices have had to be re-thought. The old-fashioned “dose and move” is now considered to be a major risk factor for increasing resistance, for example! They are important and useful products but, as with antibiotics, they need to be used with care to make sure resistance does not occur – or at least, is delayed as much as possible.

Remember, there are no new families of wormer in the pipeline, so when the ones we’ve got no longer work., that’s it…

What are the different wormers?

There are three wormer classes in cattle:

  • Benzimidazoles (white wormers)
  • Levamisoles (yellow wormers)
  • Macrocyclic Lactones (clear wormers)

In sheep, we have these three and a further two more: Amino-acetonitrile derivatives (orange wormers) and Spiro indoles (purple wormers).

What practices encourage wormer resistance?

Frequency of worming

Every time you dose a sheep or cow for parasites you increase the risk of wormer resistance on your small holding. The more frequently that livestock are wormed, the more quickly and easily worms can build a resistance. This is because we only kill susceptible worms – leaving space for those resistant worms to breed and succeed.

If you find that wormer resistance is present on your small holding, you may be finding the need to dose more regularly, change product or you might find products ineffective. Reducing reliance on these products and using them only when necessary is an initiative-taking approach.

Dose and move

Dosing animals and moving them to clean pasture used to be common guidance – now we understand that it is better to leave treated animals on pasture for a brief time. This is so the excreted resistant worms can breed with susceptible worms on the pasture, reducing the risk of breeding only resistant worm populations.

Underdosing

Another area that can encourage resistance is underdosing your sheep or cattle with wormer. This is because worms only receive a small dose of product, not enough to kill them, but enough to encourage resistance.

It is good practice to ensure all animals are weighed and dosed correctly, this can help reduce the risk of resistance. Another common way is to weigh the heaviest in the group and dose for that weight. If there is a wide range of weights, split the group and weigh the heaviest in each smaller group.

Blanket treatment

This is when all animals in a group are treated with the same drug at the same dose. This is known as ‘blanket treatment.’ Blanket treatment is one of the main drivers of wormer resistance and is quite commonly seen.

If you have any concerns about worms, resistance, worm egg counts or how to administer a product, please seek advice from your veterinary surgeon or SQP.