Influence of dietary protein on the apparent absorption and retention of selenium in sheep

Serra, A. B.; Serra, S. D.; Fujihara, T.

doi:1996.9.5.551

Article

Ruminant Nutrition and Forage Utilization

Asian-Australasian Journal of Animal Sciences 1996;9(5): 551-556.
https://doi.org/10.5713/ajas.1996.551 Published online October 1, 1996.

Influence of dietary protein on the apparent absorption and retention of selenium in sheep

A. B. Serra, S. D. Serra, T. Fujihara

Abstract

Selenium (Se) apparent absorption and retention in sheep as influenced by diets differing in protein content through soybean meal supplementation was studied. A 3 횞 3 Latin square design was used with three Japanese Corriedale wethers(45 kg average body weight), three periods, and three dietary treatments. In each period, 7 d dietary adjustment was followed by 5 d total collection of urine and feces. The three dietary treatments were : Diet 1, without soybean meal supplementation(14% crude protein, CP); Diet 2, with 10% soybean meal supplementation(16.5% CP); and Diet 3, with 20% soybean meal supplementation(19% CP). All the diets had a Se supplementation in the form of sodium selenite at 0.2 mg Se/kg dietary DM. The dietary DM intake of the animals was 2% of their body weight. No significant differences were obtained among the three dietary treatments of the Se balance of the animals. However, as percent of Se intake, only urinary Se concentration of Diet 3 was markedly lower(p<0.05) than the other diets. Fecal Se as percent of Se intake followed the trend of Diet 3>Diet 2>Diet 1 resulting a Se absorbed as percent of Se intake of 58.9%, 62.3% and 68.2% for Diets 3, 2 and 1, respectively but their differences among each other were insignificant. No significant differences that were observed either on Se retained as percent of intake(Diet 1, 48.2%; Diet 2, 45.2%; Diet 3, 46.0%) or Se retained as percent of Se absorbed(Diet 1, 70.7%; Diet 2, 72.4%; Diet 3, 77.9%). Significant correlation coefficients among the various measures of Se utilization were also observed. Regression analysis showed the following equation: Y = 93.8 - 1.86X(p<0.05, r2 = 0.48), where Y is the Se absorbed as percent of Se intake(%) and X is the dietary protein content(%). This study concludes that Se requirement in sheep is greater when dietary protein content is high.

Keywords: Selenium; Selinite; Selinium Absorption; Selenium Retention; Dietary Protein