TOPICS OF THE WEEK

Press, Volume XCV, Issue 28257, 20 April 1957, Page 9

TOPICS OF THE WEEK

DISEASE IN EWES Pregnancy toxaemia (twinlamb disease), which often causes heavy loss to sheep farmers, is the subject of investigation at a number of centres in Britain, including the Nuffield Institute for Medical Research at Oxford. Recent observations from this institute have suggested that excessive weight gains in early pregnancy might predispose ewes to pregnancy toxaemia if they are subjected to changes in nutrition or other stresses in late pregnancy. On this assumption, a system oi ante-natal care has been designed as an attempt to control the occurrence of this disease.

Broadly speaking, the system has aimed at keeping down weight gains in early pregnancy by controlling food intake, either by varying the size of the fold or the amount of grazing allowed. About 6-8 weeks before lambing, depending upon the weather, the ration has been increased, either by allowing access to improved grazing or, more usually, by feeding supplements of corn, hay, etc. At the same time, provision has been made for the ewes to have plenty of exercise.

The results over the last three years with some 50 lowland flocks in England and Scotland are most encouraging. Lambing percentage has been maintained, and, in some instances, increased. At the same time, the number of cases of toxaemia was greatly reduced, and the mortality rate fell from about 15 per 1000 to about 2 per 1000. In the case of some commercial flocks in southern England, the drop is reported to have been even more marked. These, of course, are only preliminary results, and the study will obviously have to be continued to take into account the well-known natural fluctuations in the occurrence of the disease from year to year.