Impact of dietary protein levels on adrenaline sensitivity of beef cattle
The aim of the current study was to evaluate the impact of dietary protein on adrenaline sensitivity in an effort to determine if this is increasing the incidence of dark cutting in beef cattle. Eighteen Angus steers, approximately 12 month old, with an average live weight of 284±23 kg were used. The animals were randomly split into 10.4, 20.1 and 29.7% dietary protein levels and were challenged with 3 levels of adrenaline (1, 3 and 5 ug/kg live weight). The diets were balanced according to NRC (2016) with minerals and metabolizable energy remained constant for a growth daily gain of 1 kg. Plasma was analysed for non-esterified fatty acids (NEFA) and glucose concentration and area under curve over time 10 minutes post-challenge (AUC10) was calculated to reflect the tissue responses to adrenaline. There was a significant effect of diet on glucose basal concentration where 10% dietary protein had a higher adrenaline response within the liver or muscle comparing to 20 and 30% dietary protein.