Tom Clune

This chapter addresses the nutritional, husbandry and disease processes which affect ewes and their foetuses in the time from early pregnancy to parturition and through early lactation. Nutrition of the ewe through pregnancy has a major effect on her health, her ability to deliver robust and healthy lambs and her ability to bond with, protect and nourish her lambs in the neonatal period. It also has major effects on the survival rate of the lambs in the neonatal period. Some of the most common clinical diseases which affect ewes during pregnancy are pregnancy toxaemia and hypocalcaemia, and these conditions are most effectively prevented by flock management strategies. There are numerous infectious agents which can cause abortion in ewes. Many of these agents can also cause stillbirths and the birth of lambs of low birthweight and poor viability. The normal behaviours of ewes and lambs at parturition are described. Factors which interfere with the development of a strong bond between ewes and lambs, and factors which reduce the intake of sufficient nutrients by lambs soon after birth, have a major effect on the probability of lamb survival in the first few days of life. Perinatal mortality in lambs is one of the most important causes of economic loss to the Australian sheep industry. Veterinary investigations of perinatal mortality can identify the steps that need to be taken to reduce perinatal mortality on sheep farms. Adequate nutrition of the lactating ewe is essential to achieve satisfactory health and growth in their lambs. The most important disease condition of the lactating ewe is mastitis.