Effects of supplementation with plant extract product containing carvacrol, cinnamaldehyde and capsaicin on serum metabolites and enzymes during the finishing phase of feedlot-fed bull calves

Abstract This study investigated the in vivo effects of a commercial blend of plant extracts (carvacrol, cinnamaldehyde and capsaicin) on serum metabolic parameters closely connected with energy and protein metabolism (glucose; l -lactate; non-esterified fatty acids, NEFA; urea nitrogen, SUN; creatinine; total protein, TSP) and enzymes associated with hepatic function (aspartate-aminotransferase, AST and gamma-glutamyl transferase, GGT) in finishing-stage Belgian Blue bull calves maintained in a commercial feedlot. Monitoring was performed over 86 days in 24 animals randomly allotted to two groups: (1) a control group (CTR, no supplementation; n  = 10), and (2) a group receiving dietary supplementation with a commercial blend of plant extracts (PEX, 100 mg/kg DM of concentrate; n  = 14). Under the conditions of our study, supplementation with the commercial blend did not give detrimental effects, but the opposite: the decrease in serum l -lactate, NEFA and creatinine levels and the increase in SUN concentrations; suggests an improvement in the energy status and protein turnover of the supplemented animals.