Inorganic Sodium Selenite Research Articles

Effect of Selenium Source and Litter Type on Broiler Feathering

Inorganic sodium selenite (NaSe; 0.1 and 0.3 ppm) and organic selenium yeast (Sel Plex 50: OR; 0.1 and 0.3 ppm) were provided in the diets of broilers placed on four different litter types: 1) ACR paper (diced recycled low-density fiber paper treated with boric acid, 4.5%), 2) shavings (pine wood shavings), 3) diced/cross-cut news print, or 4) 50% mixture of ACR and shavings, in a 32-pen broiler house with curtain side walls. Subjective body feathering scores ranging from 0 (no feathers) to 5 (best) were determined at 3, 5, and 6 wk of age. In experiment 1, feather scores at 6 wk of age were improved significantly with OR supplementation at 0.3 ppm compare to all other selenium treatments, and in Experiment 2 both levels of OR supplementation were associated with improved feathering compared to NaSe supplementation. ACR paper caused reduced feathering in both experiments, and neither NaSe nor OR were sufficient to overcome the problem. In both experiments, OR was associated with better feathering for broilers on all litters at all ages. Performance parameters such as feed conversion ratios were not affected by selenium source even though feathering, an energetically expensive function, was improved in the OR-fed birds.

Effects of organic and inorganic selenium supplementation on selenoenzyme activity in blood lymphoctyes, granulocytes, platelets and erythrocytes

The blood selenium (Se) concentration in the U.K. population has declined by approx. 50% between 1974 and 1991, reflecting a large decrease in dietary Se supply, with intakes only half the reference nutrient intake of 1 microg/kg body weight. Tissue levels of Se are readily influenced by dietary intake. Therefore selenoprotein activity may be sub-optimal due to low Se status, and thus compromise normal cell function. To examine the effects of changing Se intake on selenoproteins, we have determined the relative effectiveness of organic selenomethionine and inorganic sodium selenite (50 microg of Se daily for 28 days) in modulating glutathione peroxidase activities in blood cells from 45 healthy men and women, from a U.K. population. Transient and acute changes in lymphocyte, granulocyte and platelet phospholipid-hydroperoxide glutathione peroxidase (GPx4) activity occurred by day 7 or 14 of sodium selenite treatment and by day 7 in lymphocytes from selenomethionine-treated subjects compared with controls taking a placebo. In contrast, GPx4 activity in granulocytes and platelets in the selenomethionine group increased gradually over the 28 days. Cytosolic glutathione peroxidase (GPx1) activity in these blood cells from both treatment groups increased gradually over the 28 days. For each cellular selenoenzyme activity a significant inter-individual difference (P<0.001) in the extent of the response to Se supplementation was observed, but this was not related to blood Se concentrations either before or after treatments. Significant inverse correlations were evident between baseline enzyme activities and percentage change in activity after 28 days of supplementation [e.g. lymphocyte GPx4, r=-0.695 (P<0.001)], indicating that pre-treatment activity may be sub-optimal as a result of poor Se status. The different and contrasting effects that Se supplementation had on blood selenoenzyme activities may be indicative of a difference in metabolic need for Se regulated at the level of Se-dependent cell function.

Effect of supplemental selenium for beef cows on the performance and tissue selenium concentrations of cows and suckling calves.

Summary The effect of supplemental dietary selenium on tissue selenium concentrations in cows and their nursing calves was determined. In Exp. 1, beef cows were fed one of two protein supplements, a soybean meal-corn meal mixture or linseed meal at the equivalent of 908 g/head/ day. The soybean meal-corn meal mixture contained 98 ppb selenium and the linseed meal, 1,186 ppb selenium on a dry matter basis. Five treatments were used, with three or four cows and their calves assigned to each. The treatments were (1) soybean meal-corn meal supplement alone and (2 and 3) in combination with the equivalent of .1 or .2 ppm added selenium in the total diet, and (4)the linseed meal supplement alone and (5) in combination with the equivalent of .5 ppm added selenium in the total diet. The added selenium, either in the form of linseed meal or as inorganic sodium selenite, tended to increase concentrations of selenium in the plasma, milk and liver of the cows and in the plasma, muscle and liver of the calves. Tissue selenium concentrations of calves were greater (P<.01) with linseed meal alone than with a comparable selenium intake from soybean meal plus inorganic sodium selenite. Linseed meal plus the equiv#lent of .5 ppm selenium in the total diet resulted in