Effect of selenium on the reproductive performance of ewes and white muscle disease in lambs

A study using 60 Awassi ewes fed either a control (unsupplemented) diet or one containing selenium-enriched yeast (Selplex™, Alltech Incorporated, USA) at a dose rate of 0.2 mg/kg diet was conducted to investigate the effects on white muscle disease occurrence in progeny. The effects of organic selenium on oestrus, fertility, lamb birth weights, weaning weights and rates of white muscle disease were recorded. There was no effect of organic selenium supplementation on pregnancy rates as recorded by ultrasound at 40 and 80 days after mating (P> 0.05). Likewise, there were no significant differences in lambing, single or twinning rates between the control ewes and those receiving organic selenium. Birth and weaning weights were not significantly different in either single or twin lambs from either control or Se-supplemented ewes. However, the Se-supplemented ewes gave birth to lambs which had significantly less incidence of white muscle disease (37.5% versus 3.3%; P< 0.001).