The aim of this study was to investigate the efficacy of dietary endotoxin binders [bentonite (BEN) and Saccharomyces cerevisiae cell wall (SCW)] on acute-phase protein (APP) response and liver function in cows during the transition period. Twenty-four multiparous Holstein cows were randomly assigned to one of four treatment groups. The experimental groups consisted of (1) the basal diet (BD) + SCW, (2) BD + SCW + BEN, (3) BD + BEN, and (4) BD (control). Blood samples were taken at 1, 3 and 4 weeks before and 1 and 3 weeks after parturition and serum concentrations of non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHBA), glucose, haptoglobin (Hp), serum amyloid A(SAA), albumin, g-glutamyl transferase (GGT), aspartate aminotransferase (AST), cholesterol, iron, and lipopolysaccharide (LPS) were measured. The concentrations of LPS, SAA, albumin, and Hp in the blood were within reference range at all times. The level of blood LPS was not high enough to initiate an APP response. Mean BHBA concentration was highest at 1 week after calving. For NEFA, the pattern was similar, with a peak at 1 week after calving. Cholesterol concentration was lower in the SCW group, probably due to a lower lipoprotein concentration. Mean AST concentration was highest at 1 week after calving, especially in the SCW + BEN group. The results of a current study showed that, if the carbohydrate level is not high in the diet to cause rumen acidosis, it is not profitable to supplement BEN and SCW for adsorbing endotoxins in the diet, in transition cows.
Keywords: Acute-phase protein response; Dairy cow; Endotoxin binders; Liver function; Transition period.