A couple of standard management practices for cow_calf producers are castrating bull calves to sell feeder steers with substantially higher market prices than feeder bulls, and the use of calf growth implants to enhance weight gain and sale weight of steer calves. Traditionally castration is done at birth by banding or at spring processing at 30_50 days by banding or knife cutting, with implants placed in the ear at this time. However, in some instances castration is delayed until fall. This is done for various reasons including: providing more opportunity to develop calves before decisions are made regarding which calves have the best potential to be developed as breeding stock; a lack of labor and time in the busy spring; or to take advantage of growth enhancing hormones levels in intact bulls. Implanting is routine on some operation, while others chose not to use implants to make cattle eligible for buyers seeking non-implanted calves, to qualify for natural beef designated programs or simply aren’t convinced of the value and effort.

While various studies and numerous data over time addresses the issues of the value of implants and the best time to castrate, recent Kansas State University trial using March born calves provides some recent bench marks. Early June castrated calves were compared to herd mates castrated at weaning in mid-October. The early castrated group also included a comparison of implanted with Synovec to no implants.

Early cut implanted and intact bull calves weighted the same at weaning (226 days) and about 15 pounds more than non-implanted steers. Following a 28 day preconditioning feeding period after weaning in which calves got free choice brome hay and 5 lbs/hd/day of a pelleted commercial feed, the early castrated implanted steers out weighed the weaning cut calves and non-implanted early cut calves by about 20 pounds. Calves in the trial received spring and pre-weaning vaccinations and ran on summer pasture with out creep feed.

This suggests non-implanted steer calves should sell for about 3¢/lb more to compensate for lost weaning weight for calves with the growth potential and nutrition to weigh 550_600 lbs at 7 ½ months of age. The magnitude is likely greater with higher growth and nutrition such as with large creep fed calves. When castration decisions can be made early, bulls should be steered at a young age to minimize stress, latter performance set back, and provide greater marketing flexibility. If calves will be fed for a longer period of time as is typical with backgrounding or feeding to finish one might expect latter performance to partially compensate for the set back in performance with late castration.