Fluke increases risk of Black disease in sheep

Sheep producers should check the vaccination status of their sheep to reduce the risk of Black disease resulting from fluke-induced liver damage. 

Intervet’s Rosemary Booth says there is a lot of evidence to suggest that the damage to the liver caused by fluke infestations will increase its susceptibility to clostridial diseases, particularly Black disease caused by Clostridium novyi. 

Black disease bacteria thrive in the damage caused by fluke as they bore through the liver, and the first symptom is often sudden death of seemingly healthy animals.  Sheep vaccinated against C novyi with, for example, Heptavac-P Plus, are much less likely to succumb to the effects of Black disease than those that are not vaccinated. 

Ms Booth also highlights that sheep under stress, such as that resulting from a fluke infestation, will be more susceptible to pasteurella, increasing the requirement that all animals are treated with a combined clostridial disease and pasteurella vaccine. 

The exceptionally warm spring, followed by persistent wet weather since the middle of May, means that the fluke threat is currently high.  Producers should ensure that their flocks are treated with an effective flukicide and vaccinated against clostridial diseases to prevent sudden and costly losses caused by fluke-induced Black disease.