Levadura viva (Saccharomyces cerevisiae) en la degradabilidad in vitro de una dieta para bovinos basada en forraje más concentrado

espanolSe evaluaron cuatro niveles de cultivo de levadura viva (Saccharomyces cerevisiae) en la digestibilidad in vitro de una dieta para bovinos basada en forraje mas concentrado. Se utilizo liquido ruminal de dos toros fistulados, como inoculo bacteriano. Se emplearon dos incubadores Ankom® para digestibilidad in vitro, donde se depositaron bolsas F57 (Ankom Technology) que contenian las muestras de tratamientos experimentales. Los tratamientos fueron; T1: dieta testigo a base de forraje mas concentrado, T2: T1 mas 1 g de CL (Cultivo de levadura) kg-1 de alimento, T3: T1+2 g de CL kg-1 de alimento y T4: T1+3 g de CL kg-1 de alimento. La incubacion se efectuo en siete tiempos; y la degradacion se detuvo mediante refrigeracion a 4 oC. El experimento duro 90 dias. Se evidencio a las 3, 12 y 72 h de incubacion ruminal, la degradabilidad in vitro (DRIV) de la materia seca (DIMS), no presento cambios por efecto de la suplementacion del CL. No obstante, aunque de una manera no lineal, este CL provoco diferencias para los periodos de incubacion de 0, 6, 24 y 48 horas. La DRIV de la materia organica (DIMO) tampoco presento un comportamiento lineal por efecto de la adicion creciente del CL a la dieta base, existiendo diferencias solo en los tiempos de incubacion de 3, 24 y 48 horas, pero no en el mayor tiempo de incubacion (72 h). Los CL no provocan cambios claros en la degradabilidad de las dietas estudiadas. EnglishFour levels of live yeast (Saccharomyces cerevisiae) culture in the in vitro digestibility of a more concentrated forage based cattle diet were evaluated. Ruminal fluid of two fistulated bulls was used, as a bacterial inoculum. Two Ankom® incubators were used for in vitro digestibility, where F57 bags (Ankom Technology) containing the samples of experimental treatments were deposited. The treatments were; T1: control diet with more concentrated forage, T2: T1 plus 1 g of CL (Yeast Culture) kg-1 of feed, T3: T1 plus 2 g of CL kg-1 of feed and T4: T1 plus 3 g of CL kg-1 of food. The experiment was developed in the Laboratory of Nutrition Rumiology and Metabolism with a duration of 90 days. In vitro dry matter degradability (DIMS) showed no changes at 3, 12 and 72 h of ruminal incubation because of CL supplementation. However, although in a non-linear manner, this CL caused differences for the incubation periods of 0, 6, 24 and 48 hours. The DRIV of organic matter (DIMO) did not present a linear behavior because of the increasing addition of CL to the base diet. There were differences only in incubation times of 3, 24 and 48 hours, but not in the longest incubation time (72 h). CLs do not cause clear changes in the degradability of the diets studied.