The Veterinary Medicines Directorate (VMD) has reported a number of cattle deaths after incorrect administration of cattle worming boluses.

Reports reveal cattle have shown signs of difficulty swallowing, excessive salivation, lack of appetite and wasting, said the VMD’s Fabia Dyer.

“Animals can survive for several days, but experience great discomfort before death.”

On post-mortem examination, the bolus is found to be lodged in the throat or oesophagus.

Cases have also been reported where the bolus has been administered into the windpipe, she said.

Such animals show signs of extreme distress and die within minutes.

“There is evidence that many incidents occur in fractious cattle or at the end of a worming session involving large numbers of animals.”

Producers using boluses for worm control this season should read makers’ instructions first, she advised.

“In particular, care should be taken to avoid treating animals outside the appropriate weight range stated in the product literature.

Users should also make sure the bolus is loaded correctly.”