Coccidiosis

 

By Dr Rob Marshall

 

Coccidiosis is a major disease of chickens that results in bloody diarrhoea, high mortality in young birds, severe sudden onset depression, poor growth due to an interruption of feeding and digestion processes and an increased susceptibility to other disease agents such as E. Coli infections, worms, Marek’s Disease and Respiratory Diseases.

 

Prevention programmes are recommended against Coccidiosis because already infected birds will usually die and treatments are usually ineffective by the time symptoms appear.

 

Although immunity develops quickly in young chickens after exposure and gives protection against later outbreaks repeat monthly treatments are necessary because there are 9 different forms of Coccidiosis with no cross immunity occurring between them. Each type of Coccidiosis causes separate and distinct recognisable diseases independent of the others. This means multiple outbreaks can occur within the same flock giving the false impression that a particular coccidiosis medicine is ineffective.

 

Prevention is the best cure. Routine monthly Coccidiosis treatments should be given to young chickens starting at 6 weeks of age. These should continue until they are 6 months old. These monthly repeat treatments are highly effective in preventing the disease.

 

Coccidiosis is usually a problem of young chickens up to 6 months of age, however outbreaks may occur in adults that have not been exposed to a particular form (species) of Coccidiosis early in life. Therefore, in flocks where Coccidiosis is a recurrent problem, adult birds shouldalso receive 2 days of preventative treatment in early autumn, early spring and whenever there is excessive rain during warmer weather.

 

For more information about Coccidiosis prevention refer to:

 

• The "Raising Chickens from Eggs" article in this Disease and Remedy Section.

• The Young Bird Programme in the Poultry side bar.