14 May 1999

Buy with care to cut disease

CUT risks of introducing disease by making essential purchases of breeding stock from the same known source.

That is the advice Midlands-based Signet sheep consultant Maurice Jones gives to producers considering running a closed flock.

"Running a pure flock is the ultimate way of achieving closed flock status. But there are few breeds that can be run as a pure flock and meet the required performance criteria demanded of a commercially viable, large-scale enterprise in terms of lambing percentage and quality prime lambs," warns Mr Jones.

"The Lleyn is one breed that can be managed as a pure flock and still produce performance results that can match figures achieved by the Mule. But for most commercial lamb producers who want to run a closed flock there has to be some cross-breeding and that means some stock has to be bought-in."

Mr Jones believes the concept of closed-flock management can be achieved by imposing strict control on the source of rams and replacement females.

"Only buy-in tups and ewes from one or two sources that have proven health status. Lambing percentage can slip away over two or three years so make sure you buy rams that have been born as twins.

"Closed flocks which buy in stock less frequently need to make doubly sure of their tups. It is best to buy shearlings so you can see how the ram looks as a mature sheep; you can see his skeletal development and make a more balanced decision compared with buying a ram lamb."