Selenium supplementation of grazing sheep 3. effects of supplementation of ewes before and or after lambing on the selenium status blood enzyme activities and the growth of their lambs
Australian Journal of Agricultural Research 31(5): 1017-1028
ISSN/ISBN: 0004-9409 Accession: 006385426
The effects of oral Se administration to ewes during pregnancy and/or following parturition on ewe fertility, Se status of the ewes until lambing and of their lambs from birth to 70 days of age, on plasma enzyme activities and on lamb growth were investigated by using 4 groups of ewes grazing pasture in the low Se region of New England [Australia]. Se treatment prior to parturition resulted in significantly higher activities of erythrocyte glutathione peroxidase of both ewes and lambs at lambing, though Se status of untreated ewes and lambs was adequate. There were significant increases in activities of erythrocyte glutathione peroxidase of lambs following Se supplementation of their dams at parturition, whereas activities of lambs with untreated dams declined; depending on Se status of the dam, lambs received varying Se supplements via milk. There were no significant effects of Se treatment on ewe fertility or on growth patterns of groups of lambs. From 49 days of age, lambs whose dams received Se at parturition were significantly heavier. Results are discussed in relation to recommended schedules for oral Se supplementation and the diagnosis of Se inadequacy in grazing sheep.