Although it may not feel like it, Spring is just around the corner and with it, the risk of Coccidiosis and Nematodirus battus hitting your lambs. Amy Glanvill talks us through the symptoms and preventative measures.
Coccidiosis is caused by the protozoan Eimeria spp. and can affect lambs at both housing and pasture especially in intensive farming systems, although any stress such as weaning, mixed age groups and adverse weather can also increase incidence. Eimeria initially enters the environment from the ewe but due to its short life cycle in the lamb, quickly increases in number. Coccidiosis affects lambs at four to six weeks old and presents as:
- Poor growth rates / weight loss
- Scour (with or without mucus and blood)
- Death (can be seen without prior symptoms)
Although medication with antiproducts are indicated upon diagnosis, husbandry management is also important, for example, improving hygiene and stocking density.
Unlike coccidiosis, Nematodirus battus is only seen in lambs at grass and is a worm instead of a protozoan. Nematodirus spreads from a lamb crop in one year to the lambs born in the next and has the potential to hit flocks hard this year. The cold weather we have experienced lately delays hatching of eggs on pasture. If this is followed by a sudden rise in temperature, then mass hatching of larvae coinciding with 6-12 week old lambs grazing pasture can cause severe production losses and even deaths.
Nematodirus will usually affect lambs at a slightly older age than coccidiosis although they can present together. Clinical signs are similar to coccidiosis.
Are my lambs at risk of Nematodirus?
- Was the pasture grazed by lambs or calves last spring?
- Are your lambs old enough to be eating significant amounts of grass?
- Is coccidiosis a problem on your farm?
- Has there been a cold snap followed by warmer weather?
- Are your lambs under other stresses e.g. mixed age groups, high stocking density
Luckily, both these diseases can be diagnosed by a simple worm egg count test in house with a fast turnaround. Therefore, if you are concerned about either of these diseases, contact your vet or simply bring in a pooled muck sample. It is worth bearing in mind that nematodirus cannot always be diagnosed by egg counts as symptoms are sometimes seen before any eggs are produced. As usual, please contact your vet if you are concerned about your lambs.
When treating parasites in sheep it is important that the correct medication is used so that the specific parasite can be targeted and wormer resistance can be limited. Nematodirus, unlike most other worms, can be treated with a white (benzimadazole) drench.
Jess Clayton gives us her view on controlling Nematodirus as an SQP and VetTech:
Our VetTech’s are able to do worm egg count tests on your flock if you’re concerned about the prospect of worms this spring. But we ultimately want to help you control the spread of worms from season to season. Here are our top control tips:
- The best course of action is to turn lambs out with the ewes onto ‘safe pasture’ not grazed by lambs in the previous year.
- Where this isn’t possible it is best advised to use a targeted treatment plan. As mentioned by Amy, a white drench is often recommended, but seek Vet or SQP advice prior to treatment.
- Timing of treatment is critical and so be aware of the weather and follow disease forecasts on websites such as NADIS and SCOPS from March onwards. As the warmer weather normally moves from the south, we use reports of outbreaks in other parts of the country to predict when it will hit us.