A note on growth rates and maturation rates in beef bulls

Abstract
Values for weight and age of beef bulls at stud have been used to describe growth beyond the point of inflexion of the growth curve. Using the concept of ‘metabolic age’ it was shown that the maturation rate in Aberdeen Angus and Friesian bulls was close to a reported interspecies mean value. Hereford and Charolais bulls both matured relatively rapidly. Variation between individuals within a breed was consistent with the hypothesis that it is possible to select for rapid growth rate without necessarily selecting for an increase in mature size.