Selenium Availability Complemented With Sodium Selenite and Selenomethionine in Lambs

The objective of this work was to evaluate the effect of selenium (Se) supplement on the digestive function of lambs. Twenty lambs (26 ± 2.4 kg) 6 months of age were housed in metabolic cages and were cannulated in rumen and duodenum. They were used in this experiment and all of them were included in general treatment without supplement of Se: 0.12 ppm of Se (G1). Subsequently, all lambs were divided following 2 treatments: G2) with supplementation of Na2SO3, and G3 supplemented with selenometionin. Both groups provided Se at 0.64ppm. Comparisons among groups were analyzed by covariance and means treatments were carried out with the significant minimum difference test and T-student. Samples of ruminal liquid were used to determine pH, Se in bacteria, bacteria and protozoa population, volatile fatty acid concentration Se. Duodenal and fecal liquid samples were used to determine the pre-gastric, post-gastric and total digestion rates, with the inclusion of 0.4% chromic oxide as a digesta marker. The results indicated a Se effect of the diet on the passage rate in the small intestine. Se supplement in the diet with sodium selenite and selenometionin improved the passage of Se to the small intestine (65.09 vs. 218 μgSe). There were not differences on the solubility of Se, molar proportion of acetic, propionic and butyric acid. Bacteria concentration in ruminal fluid increased with both sources of Se supplement (36.8 y 54%). In conclusion, there were no differences in absorption and Se digestibility with sodium selenite or selenometionin included in the diet of lambs.