Implanting Suckling Calves: Getting the Most Out of Your Calves’ Genetic Potential

By Chris Reinhardt, Ph.D., Zinpro Corporation

Implants administered to suckling calves increase weight gain and improve efficiency, resulting in increased profit for the rancher. Anabolic implants are both safe and effective. Implanting suckling calves can enhance what the rancher has already established from a progressive genetic selection program.

Giving suckling calves an age-appropriate implant will result in 15-25 pounds increased weaning weight, depending on quality of genetics and abundance of nutrient supply. Implants will increase calf average daily gain by about 10%. If calves would normally gain 2.0 lbs/day without implants, they should gain about 2.20 lbs/day with an age-appropriate calf implant. That said, if calves would only gain 1.0 lb/day without an implant due to poor genetics or, more likely, poor nutrient availability, we should only expect calves to gain 1.10 lbs/day with implants. Given this 10% performance response, implants provide one of the greatest potential returns-on-investment from any available production technology.

The old silk purse/sow’s ear expression applies: the better the calf’s genetics, the more benefit we should expect from implanting. And the more nutrients that are available to the calf, the more benefit the calf will gain from an implant.

It is important to note that the added weight gain from a suckling calf implant stays with the calf no matter where that calf goes next. That is, if a calf is 20 pounds heavier at weaning due to the implant, it will still be 20 pounds heavier after backgrounding, after grazing, and through to slaughter than if the calf had not been implanted. An implant given today does not diminish the value or the potential performance benefit of an implant given in the next phase of production.

One key to understanding how growth-promoting implants work and how they affect growth and improve performance is that anabolic implants exert their influence through the very same biological pathways (chemical messengers, cytokines, carrier proteins, etc.) as those pathways that are altered by higher-growth genetics. The stimulus pathways are the same. Implants increase growth the same way that using a bigger bull does.

Make sure to always and only use the appropriate implant at the appropriate stage. Implants that are approved for use in suckling calves are formulated with a dosage of active compound that is specifically designed for the age and weight of suckling calves. Giving calves a dosage of implant that is not approved in suckling calves may result in delivering more active compound than the calf’s metabolism can fully utilize; this excess dosage may potentially have a