Avaliação de diferentes fontes e níveis de selênio na dieta de leitões: digestibilidade, excreção e viabilidade econômica

Abstract

The research was carried out with the objective of evaluating the use of different sources and levels of selenium on top in the piglet diet under the parameters of digestibility, excretion and economic viability. For this, 40 piglets were used at 45 days of age, with an average initial weight of 9.45 kg ± 1.55, with 20 castrated males and 20 females of the same commercial strain (Topigs®). The animals were distributed in a randomized block design (DBC) with five treatments, which consist of: DC - Control diet without adding any additional source of selenium; DSL-0.150 - Control diet supplemented additionally with 0.150 mg / kg selenium yeast; DSS-0.150 - Control diet supplemented additionally with 0.150 mg / kg of sodium selenite; DSL-0.300 - Control diet supplemented additionally with 0.300 mg / kg selenium yeast; DSS-0.300 - Control diet supplemented additionally with 0.300 mg / kg of sodium selenite, with four replicates and two animals per experimental unit. The method of partial collection of feces was used, and the determination of selenium in feces and feed was performed, the determination of economic viability, was calculated according to the equation proposed by Bellaver et al. (1985) and for the Economic Efficiency Index (IEE) and the Cost Index (CI) was according to the methodology proposed by Barbosa et al. (1992). At the end of the experimental period, feces and feed were taken to the laboratory to determine the concentration of selenium in the feces (Sefezes), digestible selenium (Sediges), digestibility coefficient (CDSe) and selenium excretion (SeExc). Where there was an interaction effect (P> 0.05) for the variables selenium concentration in feces (Sefezes), digestible selenium (Sediges) and the selenium digestibility coefficient (CDSe), for the level of selenium, as well as for source of mineral supplementation used, with selenium yeast at the level of 0.150 mg / kg with lower concentration of selenium in the feces, consequently it presented a better digestibility and digestible selenium. Already, the sodium selenite diet (DSS) did not differ statistically regardless of the level for concentration of selenium in the feces, for digestibility coefficient it presented at the level 0.150 mg / kg a lower digestibility coefficient. being that, for the selenium content excreted, in the two units what influenced (P <0.05) was the level of supplementation and not the source, observing the same with the variable in relation to the control diet. Supplementation of yeast selenium at the level of 0.15mg / kg, improves the digestibility of selenium in the diet, reducing the excretion of selenium in the feces, reflecting in better economic viability.