MUSCLE AND KIDNEY SELENIUM LEVELS IN CALVES AND LAMBS RAISED IN VARIOUS PARTS OF CANADA: RELATIONSHIP TO SELENIUM CONCENTRATIONS IN PLANTS AND POSSIBLY HUMAN INTAKES

Abstract

A survey was conducted to estimate the natural concentrations of selenium in tissues of cattle and sheep raised in different geographical areas of Canada. Beef calf and lamb skeletal muscle and kidney samples were obtained from animals fed and raised locally at various Agriculture Canada Research Stations across Canada. A high proportion of samples obtained from the eastern provinces (Ontario and eastward) contained low selenium levels (skeletal muscle dry matter, mean ± SE 0.28 ± 0.03; kidney cortex dry matter 2.60 ± 0.22) whereas much higher selenium levels were present in these tissues from Manitoba, Saskatchewan, Alberta, and British Columbia (skeletal muscle dry matter, 1.01 ± 0.15; kidney cortex dry matter, 5.84 ± 0.42). These data correspond to a similar east versus prairie distribution for selenium in Canadian feed ingredients as reported earlier in the literature by another author and with the higher incidence of selenium deficiencies occurring in livestock raised in eastern Canada than in the prairies. Most of the eastern tissue selenium levels were comparable with those reported for selenium-deficient animals raised in the United States and New Zealand. The results suggest that practical measures for ensuring livestock in eastern Canada of adequate selenium and vitamin E intakes are required to protect against onset of deficiency conditions.