Duck hunting – danger time for sheep farms
It’s that time of the year when sheep farmers ‘‘on-farm’’ control of sheep measles gets tested’’ says Dan Lynch Project Manager of Ovis Management Ltd, the meat industry group tasked with education and awareness around sheep measles. ‘‘Each May across the country hundreds if not thousands of dogs are taken on to farms for duck shooting. The weeks leading up to opening day should be used by sheep farmers to get on the front foot by requiring all visiting dogs to be treated for sheep measles before entry’’. He commented that each year a number of sheep farmers have their generosity in letting duck hunters come onto their farm with their dogs come back to haunt them when they start to see sheep measles notifications showing up on their kill sheets.
Not only can sheep measles cysts in lambs and sheep result in financial loss for the farmers, because the majority of the cysts are deep in the meat they are difficult to detect during processing. While an aesthetic defect their presence is unacceptable to consumers.
Dogs become infected with sheep measles by eating sheep or goat meat containing viable cysts. The cysts hatch in the dog’s intestine becoming a tapeworm that around 35 days later is shedding hundreds of thousands of eggs when the dog defecates. The eggs on the pasture can survive for up to six months and can spread over a large area. And, the eggs when eaten by sheep develop into cysts deep in muscle tissue where after three or more months they die and become calcified.
Because dogs can still be shedding eggs up to 48 hours after treatment it is important to make sure that all visiting dogs are treated for sheep measles at least two days before entry ‘‘It’s too late to treat dogs when they turn up at the front gate and that message needs to be passed on to dog owners when making arrangements’’.
Dog owners have a choice of drugs for treating their dogs available from their local vet or, in some cases, rural supply stores ranging from all wormer drugs to cheaper straight praziquantel tablets. Lynch said the prevalence of sheep measles detected in processing plants continues to be low with last season’s prevalence at 0.62% compared to 0.67% the previous year. While that is good the extremely high reproductive rate of this parasite means any lessening of control will quickly result in an increase in prevalence levels with associated costs to farmers. Key Points All dogs should be treated with praziquantel at least 48 hours before going on or near sheep pasture.
Dogs should only be fed frozen or cooked sheep or goat meat.
For more information, visit sheepmeasles.co.nz
Dan Lynch Project Manager 06 354 0451 firstname.lastname@example.org