Coccidiosis in calves – what it is and how to spot it
- What is coccidiosis?
- What are the clinical signs?
- Is my herd at risk?
- How do I diagnose coccidiosis?
- How do I treat coccidiosis?
- How do I prevent coccidiosis?
Coccidiosis is an intestinal, parasitic disease of livestock, characterised by weight loss, diarrhoea and ill thrift. It usually affects youngstock between 3 weeks and 9 months of age. It is widespread and present on most UK farms, but rarely fatal, instead causing severe production losses.
What is coccidiosis?
Coccidiosis is caused by the protozoan parasite Eimeria. There are at least 13 different species of Eimeria that affect cattle but the main disease-causing species are E. bovis, E. alabamensis and E. zuernii. Coccidiosis is host-specific, meaning calves cannot infect lambs and vice versa.
Coccidiosis is most seen in weaned calves, associated with high stocking densities and dirty or wet conditions, however, it can also be seen in both beef and dairy calves at pasture, most commonly in the spring.
The severity of the disease seen is influenced by the level of challenge i.e. number of oocysts ingested, and the animal’s immune status. This means stressed animals, or those with concurrent disease are more likely to be severely affected. Coccidiosis can cause subclinical infections, and often by the time clinical disease is apparent, there will have been significant economic losses across the group due to reduced growth rates and poor feed conversion efficiency. Subclinical losses are thought to cost up to £60 per animal in UK dairy herds.1
Eimeria life cycle:
Oocysts (eggs) are shed in the faeces of cattle. They can survive in the environment for up to 18 months and mature in the environment for several days when temperature and moisture conditions are suitable. Once mature, if they are ingested by young calves without immunity, they enter the cells lining the gut and multiply rapidly, causing severe damage to the gut. Due to the multiplication within the animal, one infected calf can shed huge numbers of oocysts in their faeces - leading to massive environmental contamination and a high infection challenge for other at-risk animals.
This process usually takes around 21 days.
What are the clinical signs?
Clinical signs of coccidiosis are usually a result of severe damage to the gut by the parasite and resulting loss of absorptive capacity for water and nutrients.
Clinical signs include:
- Diarrhoea, frequently with blood and mucus
- Dehydration
- Straining and occasionally passing sloughed intestinal mucosa
- Bloodstained perineum
- Occasionally rectal prolapse may be seen as a consequence of straining
- Reduced appetite
- Weight loss
Less severe cases may show:
- Reduced weight gain
- Poor coat
- Dull appearance
Is my herd at risk?
Intensive systems with high stocking densities, both indoor and outdoor, are more at risk of coccidiosis outbreaks. Poor hygiene, such as wet bedding, stress and concurrent disease are also contributing factors.
How do I diagnose coccidiosis?
Diagnosis can be made on clinical signs in some cases, however as discussed, by the time animals show clinical signs, economic losses will have already occurred.
Faecal examination to identify oocysts is a quick and relatively easy way to confirm infection, however, needs to be interpreted with care. Counts from individuals may vary and animals early in the disease course may have low oocyst counts. Diarrhoea may dilute the sample, giving an artificially low count, and heavily blood-contaminated samples from severely affected animals may be unsuitable for examination.
Finally, not all species of coccidia cause disease, so lab testing may be required for the identification of disease-causing species.
How do I treat coccidiosis?
Mild cases are often self-limiting, however, oral drenches containing diclazuril, such as Dycoxan , or toltrazuril, such as Chanox Multi (Ireland Only) , or in-feed medications are licenced for the control and prevention of coccidiosis. The choice of product depends on the age of the animals, method of administration and how far in the disease course they are.
When coccidiosis is identified, all animals in the group must be treated as they are likely to have been exposed to infection. Severely affected animals may also require supportive treatment and fluids.
How do I prevent coccidiosis?
Prevention relies on good hygiene and management to limit the build-up of oocysts in the environment, alongside good overall calf health:
- Keep bedding or ground dry, particularly around feed and water troughs
- Good ventilation in calf housing to improve drying
- Avoid mixing age groups, as older animals may shed oocysts and infect younger calves
- Minimise stress and overcrowding
- Minimise incidence of other diseases
If you know your youngstock are at risk, such as moving young calves to a highly contaminated then targeted oral drenches or in-feed medications can be used to prevent disease.
There will be more about the treatment and prevention of coccidiosis in our next blog.
References:
1. Taylor, M. (2016) Approaches to helping farmers reduce losses from coccidiosis. Vet Times Online, August 8 2016. chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://www.vettimes.co.uk/app/uploads/wp-post-to-pdf-enhanced-cache/1/approaches-to-helping-farmers-reduce-losses-from-coccidiosis.pdf Accessed Dec 2023.
Coccidiosis in calves – what it is and how to spot it
- What is coccidiosis?
- What are the clinical signs?
- Is my herd at risk?
- How do I diagnose coccidiosis?
- How do I treat coccidiosis?
- How do I prevent coccidiosis?
Coccidiosis is an intestinal, parasitic disease of livestock, characterised by weight loss, diarrhoea and ill thrift. It usually affects youngstock between 3 weeks and 9 months of age. It is widespread and present on most UK farms, but rarely fatal, instead causing severe production losses.
What is coccidiosis?
Coccidiosis is caused by the protozoan parasite Eimeria. There are at least 13 different species of Eimeria that affect cattle but the main disease-causing species are E. bovis, E. alabamensis and E. zuernii. Coccidiosis is host-specific, meaning calves cannot infect lambs and vice versa.
Coccidiosis is most seen in weaned calves, associated with high stocking densities and dirty or wet conditions, however, it can also be seen in both beef and dairy calves at pasture, most commonly in the spring.
The severity of the disease seen is influenced by the level of challenge i.e. number of oocysts ingested, and the animal’s immune status. This means stressed animals, or those with concurrent disease are more likely to be severely affected. Coccidiosis can cause subclinical infections, and often by the time clinical disease is apparent, there will have been significant economic losses across the group due to reduced growth rates and poor feed conversion efficiency. Subclinical losses are thought to cost up to £60 per animal in UK dairy herds.1
Eimeria life cycle:
Oocysts (eggs) are shed in the faeces of cattle. They can survive in the environment for up to 18 months and mature in the environment for several days when temperature and moisture conditions are suitable. Once mature, if they are ingested by young calves without immunity, they enter the cells lining the gut and multiply rapidly, causing severe damage to the gut. Due to the multiplication within the animal, one infected calf can shed huge numbers of oocysts in their faeces - leading to massive environmental contamination and a high infection challenge for other at-risk animals.
This process usually takes around 21 days.
What are the clinical signs?
Clinical signs of coccidiosis are usually a result of severe damage to the gut by the parasite and resulting loss of absorptive capacity for water and nutrients.
Clinical signs include:
- Diarrhoea, frequently with blood and mucus
- Dehydration
- Straining and occasionally passing sloughed intestinal mucosa
- Bloodstained perineum
- Occasionally rectal prolapse may be seen as a consequence of straining
- Reduced appetite
- Weight loss
Less severe cases may show:
- Reduced weight gain
- Poor coat
- Dull appearance
Is my herd at risk?
Intensive systems with high stocking densities, both indoor and outdoor, are more at risk of coccidiosis outbreaks. Poor hygiene, such as wet bedding, stress and concurrent disease are also contributing factors.
How do I diagnose coccidiosis?
Diagnosis can be made on clinical signs in some cases, however as discussed, by the time animals show clinical signs, economic losses will have already occurred.
Faecal examination to identify oocysts is a quick and relatively easy way to confirm infection, however, needs to be interpreted with care. Counts from individuals may vary and animals early in the disease course may have low oocyst counts. Diarrhoea may dilute the sample, giving an artificially low count, and heavily blood-contaminated samples from severely affected animals may be unsuitable for examination.
Finally, not all species of coccidia cause disease, so lab testing may be required for the identification of disease-causing species.
How do I treat coccidiosis?
Mild cases are often self-limiting, however, oral drenches containing diclazuril, such as Dycoxan , or toltrazuril, such as Chanox Multi (Ireland Only) , or in-feed medications are licenced for the control and prevention of coccidiosis. The choice of product depends on the age of the animals, method of administration and how far in the disease course they are.
When coccidiosis is identified, all animals in the group must be treated as they are likely to have been exposed to infection. Severely affected animals may also require supportive treatment and fluids.
How do I prevent coccidiosis?
Prevention relies on good hygiene and management to limit the build-up of oocysts in the environment, alongside good overall calf health:
- Keep bedding or ground dry, particularly around feed and water troughs
- Good ventilation in calf housing to improve drying
- Avoid mixing age groups, as older animals may shed oocysts and infect younger calves
- Minimise stress and overcrowding
- Minimise incidence of other diseases
If you know your youngstock are at risk, such as moving young calves to a highly contaminated then targeted oral drenches or in-feed medications can be used to prevent disease.
There will be more about the treatment and prevention of coccidiosis in our next blog.
References:
1. Taylor, M. (2016) Approaches to helping farmers reduce losses from coccidiosis. Vet Times Online, August 8 2016. chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://www.vettimes.co.uk/app/uploads/wp-post-to-pdf-enhanced-cache/1/approaches-to-helping-farmers-reduce-losses-from-coccidiosis.pdf Accessed Dec 2023.