Coccidiosis in lambs – treatment and prevention
- How do I prevent coccidiosis?
- How do I treat coccidiosis?
Coccidiosis is one of the most important causes of production loss in lambs in the UK and is second only to nematodirus as a cause of diarrhoea and ill thrift.1
Coccidiosis is caused by the protozoan parasite Eimeria, which invades the cells lining the intestines, causing severe damage and loss of absorptive capacity for nutrients and water. You can read more about the clinical signs and diagnosis of coccidiosis in lambs in ‘Coccidios is in lambs – what it is and how to spot it’.
How do I prevent coccidiosis?
Prevention of coccidiosis is twofold – reducing environmental contamination through hygiene, management and biosecurity, and targeted preventative treatment:
Management factors:
- Before lambing, all housing, feeding areas and equipment e.g. hurdles/creep feeders etc. should be thoroughly cleaned and disinfected with a product effective against coccidia. Only a limited number of disinfectants will kill coccidia so check the product carefully and pay attention to dilution and usage directions.
- Ensure stocking levels are optimal and keep bedding clean and dry, especially around feeding areas.
- Outdoors, regular moving of creep feeders to avoid boggy ground is recommended and avoid grazing lambs on land used for lambs the previous year where possible.
- Resistance to coccidiosis is affected by any concurrent illness or stress, so ensure adequate colostrum intake, especially in multiples.
- Adequate feed and water availability, prevention of mineral deficiencies and providing shelter will all also help to reduce disease and stress.
- Ewe nutrition is also an important factor, as if milk production is poor, lambs are likely to begin grazing earlier and will be at risk of picking up coccidia from a younger age.
Targeted treatment:
This can be given to prevent disease when a high coccidiosis challenge is expected or lambs are at significant risk, e.g. late born or molly lambs moved onto pastures where older lambs have been grazing.
- Diclazuril, such as Dycoxan , has no residual action so should be given 10-14 days after lambs are turned onto contaminated pasture. The dose may need to be repeated after three weeks if the environmental oocyst burden is high.
- Timing is key - it is important to allow exposure to the parasite for 10-14 days after turnout for immunity to develop.
How do I treat coccidiosis?
There are three licenced products for treating and preventing coccidiosis in sheep: diclazuril, toltrazuril and decoquinate.
Oral drenches:
Diclazuril (Dycoxan) is an oral drench licenced for treatment as well as prevention. All animals over three weeks of age in a group should be treated once a diagnosis is made. In clinically affected animals, full treatment success depends on the extent of gut damage and these animals will likely need other supportive treatments.
Oral drenching allows for more accurate and weight-based dosing and ensures all animals receive the right dose at the right time. Correct timing allows some exposure to the parasite before treatment, which is important for the development of immunity. Oral drenches can be more labour-intensive to administer compared to in-feed medications and there is a risk of drenching injuries if care isn’t taken.
In-feed medications:
Decoquinate is an in-feed medication that is added to creep feed under veterinary prescription. Over-treating runs the risk of blocking the development of natural immunity, meaning animals are at risk once the medicated feed is removed.
With in-feed medications, adequate protection depends on intake and cases can still be seen in small or unwell animals who consume insufficient feed.
References:
1. Macrelli, M. Dunnett, L. Mitchell, S. Carson, A. (2019) Coccidiosis in sheep The Veterinary record, 184(18), 549–550. https://doi.org/10.1136/vr.l2019