By Matt Colston, Ruminant Technical Consultant for Elanco Animal Health 

Taking time to think about your parasite control plans for the coming season is often not high on the priority list, but good planning can make a huge difference to the outcome for the lamb crop that is on the way.

Managing ewe nutrition has to be a priority, as keeping ewes in optimal body condition through pregnancy and into the lambing period gives huge benefits in terms of optimising lamb birthweights, minimising ewe health issues and ensuring plentiful supplies of good quality colostrum to give the lambs the best possible start in life.

For farms where liver fluke are present, ensuring the fluke risk to the ewes is managed as effectively as possible can be a critical factor in maintaining ewe body condition. Even a small number of liver fluke left behind will present a significant drain on resources for the ewe, so monitoring dung samples for coproantigen and fluke eggs through the second half of pregnancy can avoid some serious issues at lambing time. Treatments should be targeted to affected groups, with care taken to use the right actives to kill all the stages of fluke that are present at the time.

Worms, on the other hand, are unlikely to have much impact on ewe body condition (Haemonchus is the exception to this rule). Ewes have traditionally been treated at lambing time to reduce the worm challenge for the lambs as they start to graze. Some recent studies have shown that whole group treatment at this time is largely unnecessary, as ewes in good body condition and on an adequate plane of nutrition will mostly maintain their immunity to worms and shed very few extra worm eggs through lambing. Thin ewes, those under nutritional stress (e.g. carrying triplets) and any with other ailments (e.g. lame ewes) will most likely benefit from a worming treatment, and targeting these animals will give the same benefit as a whole flock treatment, for less time and effort and a lower selection pressure to develop resistant worm populations.

Any animals brought onto the farm (ewe lambs returning from wintering or if ewes with lambs at foot are bought in) should be given an effective quarantine treatment that includes the newer actives (e.g. group 4, orange, Zolvix™), to minimise the risk of bringing in resistant worms or worms such as Haemonchus that might not already be present on the farm. Lambs that have not yet started grazing need not be treated at this time, but as lambs start to graze a policy of routinely monitoring worm egg counts will make sure that grazing management and treatments target the right animals at the right time to keep lambs growing to their potential.