These changes are accompanied by decreased in degradation and fermentation ruminal and
therefore affected nutritional state of grazing cattle. It is well recognized that nutritional state of the grazing cattle is
related with blood glucose, urea nitrogen, non-esterified
fatty acids as well as insulin and growth hormone levels
(González-Garcia et al., 2011). However, the mechanisms by
which this metabolites and hormones may influence nutritional state of grazing cattle have not been elucidated.
Owens et al. (1991) suggested that evaluation of metabolite
and hormone profiles is paramount to our understanding of
biochemical mechanisms at work in the grazing animal.
Nevertheless, the information concerning the relationship
between diet quality, ruminal environment and nutrient
utilization in grazing cattle is quite limited. A more complete
understanding of these relationships across years and seasons, will aid in the development of nutrition and grazing
management programs that will improve efficiency of livestock production in arid rangelands. Thus, in current study is