RHEOLOGICAL MODELS USED TO CHARACTERIZE THE RUMINAL FLUID

Abstract

From the literature data resulted that the high ratio of cereals from the feeding diets
in ruminants led to the marked increase of the ruminal fluid viscosity. The studies
from the present research were done on young sheep of the Tsurcana breed divided
into two groups each comprising a number of nine heads, as follows: control group
(LM) fed with feed diet composed of alfalfa hay 60% and barley 40%; the
experimental group (LE) fed with the same basic feed diet but with an addition of
yeast (1.5 g Saccharomyces cerevisiae, Yea-Sacc1026 strain /head/day). Ruminal fluid
was sampled from the ventral sack of the slaughtered animals and analyzed with a
high-tech rheometer. The obtained data were modeled after the power law,
Herschel-Bulkley, Volcado, Casson, Cross, Carreau. Modeling was done with the
Table Curve program. A very good correlation was noticed between the
experimental data and the rheological models. This suggests that the experimental
data can be interpreted by any of the given models, and the simplest model was
selected (power law) because it is the most used model. As well, this model is at the
basis of the rheological fluid classification.