Ideal Weather for Sheep Parasites Prompts SAC Warning

The wet weather since early May has created ideal conditions for sheep parasites, particularly parasitic worms, to prosper. Farmers need to take action now if lambs are to reach their target growth rates.

"These conditions could lead to a build-up of disease problems in finishing lambs later this summer" says SAC vet Brian Hosie.

"The favourable conditions for parasites on the pasture are exacerbated by the fact that we know that on the great majority of sheep farms, not all of the available wormer products are fully effective at killing worms. Parasitic worms can reduce lamb performance so that the lambs miss their target market."

John Vipond, SAC Senior Sheep Specialist said, "There are strong market signals that consumers want lamb and not hogget. This means that it is essential that weaned lambs achieve their target growth rates off grass this summer. The target growth rate for grass-finished lambs is 220 grams per day and on clover /grass pastures 270 grams per day. Lambs from the upland areas, targeted for store market, should grow at up to 160-210 grams per day depending on the breed or cross and the pasture quality. Growth rates are a factor of the quality of feed and the occurrence of clinical and/or subclincal disease. Grass supply is not a problem on most farms this summer."

Sheep farmers should re-assess their worm control programme to make sure that they are using wormers effectively.