Serum metabolite concentrations and enzyme activities in finishing bull calves fed different types of high-grain diets (original) (raw)

Between the ages of 23 and 35 weeks, various serum metabolites and enzymes were monitored in three 10-animal groups of double-muscled Belgian Blue bull calves maintained in a feedlot in Galicia (NW Spain) on high-grain finishing diets that mainly differed in whether the grain used was predominantly maize (group M), predominantly barley (group B), or a mixture of maize and barley in approximately equal proportions (group MB). The parameters determined were glucose, non-esterified fatty acids (NEFA), total serum protein concentration (TSP), albumin, serum urea nitrogen (SUN), creatinine, aspartate aminotransferase (AST), and gamma-glutamyltransferase (GGT). Throughout the study period, all these parameters remained within the physiological ranges for beef under intensive conditions, and no animal ever showed clinical symptoms of ruminal alterations; indicating that none of these highgrain diets were detrimental to animal health. Although average serum NEFA, creatinine, albumin, AST an...