Evaluation of biochemical profile and rumen fluid parameters of sheep supplemented with Saccharomyces cerevisiae and subjected to an abrupt diet change

Abstract

This study examines rumen-fluid parameters and the biochemical profile of feedlot sheep supplemented with a commercial product composed of yeast culture and enzymatically hydrolyzed yeast during an abrupt change of diet. Eight sheep at 30 months of age, with an average weight of 40.2 ± 3.4 kg, were housed in individual stalls where they received the same diet twice daily, which was formulated according to the National Research Council [NRC] (2007). The animals were divided into two groups, namely, supplemented with Saccharomyces cerevisiae (SG, n = 4) and control (CG, n = 4). The experiment consisted of three periods: the first (seven days) consisted of an acclimation to the roughage-only diet; in the second period (five days), the animals of SG started to receive supplementation; lastly, in the third period (five days), all animals underwent a sudden change of diet, which was characterized by an alteration from 100% roughage to a 50:50 ratio (roughage:concentrate) without prior adaptation. Blood samples were collected to evaluate albumin, aspartate amino transferase, calcium, gamma glutamyl transferase, globulins, glucose, magnesium, potassium, sodium, total plasma proteins and urea. Rumen fluid was harvested to evaluate physical aspects. Supplementation increased the protozoa count; the rate of sedimentation and fluctuation remained within the physiological parameters; and total plasma proteins and globulin decreased. Therefore, the yeast appears to be a promising alternative for reducing the deleterious effects of an abrupt change of diet.