The effect of age at castration and of testosterone propionate on weight gains and carcass measurements of steers

Abstract

In one experiment studying the effects of delaying castration of bull calves from four or five months until eight months of age, under grazing conditions, there were significant differences in relative growth rate and body weights, while in another experiment, carried out at the same location in a later year, there were no differences, thus indicating a wide variability between years. In the second experiment an earlier castration (at approximately one month) was included, and some of the calves castrated at one month and at four months were implanted with testosterone propionate. There were significant differences in eye muscle area, but no differences in relative growth rates, body weights, and fat depth over eye muscle, between the group castrated at one month and those castrated at four or eight months, and between those with and without testosterone. It was concluded that testosterone secretion before puberty is of some biological importance.