Liver fluke treatment

The Department’s liver fluke forecast released towards the end of November advised farmers there is a moderate risk of liver fluke-related disease for the north, west and southwest of the country with a lower disease risk expected for the east and parts of the south. Farmers rightly do not want to take their eye off the ball and this is posing more questions as to whether treatment is required in the coming weeks. There is no clear cut answer, with the degree of risk varying between, and even within, farms. The traditional advice given in previous fluke forecasts was treating out-wintered ewes in November, January and again in April, with more regular treatment required in response to a severe fluke warning. Where sheep have been grazing on drier lands, there is a lower risk. If sheep have been grazing on marginal or wetter lands, where fluke has traditionally been a problem, then treatment is advisable in a six-to-eight week cycle depending on the severity of risk. The main risk as we approach Christmas and the New Year switches from sub-acute to chronic fluke which is traditionally characterised by ill-thrift, oedema or bottle-jaw developing (fluid accumulating under an animals jaw) and anaemia. There is still a significant risk from immature and mature fluke parasites and therefore a flukicide should be collected that treats at least both life cycle stages. Trichlabendazole-based products provide the greatest level of cover but on some areas there are known resistance issues to be mindful of. Where ewes have been treated with a product that targets immature and mature fluke parasites at housing or shortly after, it provides an opportunity to alternate to a product that covers only mature liver fluke at later stage. Careful planning is important for finishing lambs due to the long nature of withdrawal periods. Grazing sheep on the driest paddocks will help for those close to slaughter. The recent escalation of industrial action by temporary veterinary inspectors is in some cases limiting the chance to follow up on the health of livers from slaughtered animals, but if it is at all possible to follow up on this, it can provide a good insight as to the prevalence at present.

Sheep scanning

The option of pregnancy scanning was a firm favourite of farmers participating in the Sheep Welfare Scheme. For those who selected this measure, remember ewes should be scanned approximately 70-to-100 days post-ram turnout. Scanners recommend the ideal time for scanning at about day 80 to day 90 post-ram turnout with delaying scanning upwards of 100 days decreasing accuracy levels in ewes in excessive body condition. The results of the scan must be recorded in the scheme action book with the receipt (detailing the numbers scanned) maintained to show proof of scanning. Results must also be acted upon (and recorded in the scheme action book) with a feeding programme put in place that allows ewes to be managed according to litter size.

Happy Christmas

I would like to wish all readers and their families an enjoyable and safe Christmas.