Increased risk of liver fluke and black disease
UNSEASONAL wet weather is not only increasing the risk of liver fluke in livestock but also pre-disposing cattle to black disease.
That was the warning from Dr Kat Baxter-Smith, veterinary adviser with MSD Animal Health, who said: “Farmers have recently been warned over a later than normal liver fluke threat in 2024 following an unusual weather pattern during 2023. Cattle livers are therefore in danger of being rejected because of fluke and in some cases this liver damage could also allow the clostridial bacteria C. novyii to gain a foothold with rapid death o©en the result.”
She added that as a result, associated black disease is emerging as a potentially catastrophic issue as the tissue damage caused by flukes migrate through the liver provides an ideal breeding ground for clostridia bacteria.
“Clostridial toxins kill quickly, and these diseases present few clinical signs before death. As a result, more cattle should be vaccinated with a broad spectrum clostridial disease vaccine such as Bravoxin® Suspension.”
The rise in liver fluke infections and associated black disease is not the only reason why a broad-spectrum clostridial vaccination has become more popular.
There was a time that blackleg was the only clostridial disease cattle producers were aware of, but now that additional clostridial bacteria such as C. sordellii and C.perfringens A have also been identified as causes of sudden death on UK cattle farms.
Dr Baxter-Smith explained: “Clostridial bacteria take the lives of cattle and sheep regularly. These bacteria share the same environment as livestock and are everpresent – existing in soil, on pasture, within buildings and even in the tissues and intestines of cattle and sheep. Consequently, improved farm biosecurity measures will be of no benefit in controlling this group of diseases.
“The sheep industry already recognises the importance of broad-spectrum vaccination against clostridial diseases, but more cattle producers are recognising the benefit. But over the last few years, there is increased incidence of dierent clostridial diseases in far from typical circumstances,” she said.
She added that there are also many cattle deaths going undiagnosed and it is likely that many are caused by clostridial species.