Calf Implants: Use/Don’t Use At Grass Time?

While the performance benefits of implanting calves through the suckling phase is well documented, many cattlemen choose not to employ this management practice in their operations. Some who market their calves at weaning or as back-grounded calves believe it reduces buyer willingness to bid as much for similar-quality implanted calves as those that did not receive an implant. Others believe that meat quality is compromised at harvest; Return on investment by some is seen as not worth the time, effort or expense of implanting.

University research conducted over the years indicates that the benefits of calf implants vary. Genetically-superior cattle with sufficient nutrition available through heavier milking dams and available creep feed can generate five to ten percent increases in weaning weights when calves are implanted at grass time. Calves in herds with limited milk potential and feed resources may not see as much benefit from a calf implant.

For those calf implants with a duration period of 80 to 100 days, some thought for timing of the implant application should be considered: Calves given two implants of about 100 days apart have typically gained faster than calves given a single implant during the suckling phase. When cattlemen choose to only implant once during this timeframe, it is recommended that the implant be administered at about four months of age so that the activity level is present during the final 100 days prior to weaning.

While some believe that nursing implants decrease calf performance during the growing stage, work at Nebraska dispels that myth. Dr. J.K. Ward found that nursing phase implants did not decrease response to re-implantation during the growing phase. In addition, calves implanted while nursing but not re-implanted during the growing phase, gained faster (1.71 vs 1.59 lb/day) during the growing phase than calves not implanted during that timeframe. His studies also revealed that calves receiving implants during both the nursing and growing phase outgained calves implanted only during the nursing phase. (1.9 vs 1.71 lb/day)

The one time when response levels favored calves not implanted during the nursing phase was at finishing time. While all these calves did exhibit a growth response to the finishing implant, those not implanted during nursing responded better.

However, the use of implants requires careful consideration of the following factors:

    * Marketing goals: Several branded beef programs, to include “natural” and organic, prohibit the use of cattle implants in order to meet the requirements of these programs.
    * Reproductive considerations: Although research data provides mixed results of the reproductive consequences of implanting heifer calves during their pre-weaning timeframe, it is generally recommended that heifers not be implanted with a calf implant if they are considered replacement candidates for the cowherd. It is also not recommended to implant bull calves.
    * Age limitations: Label information for brands of implants as to ages when calves may be implanted and label recommendations should be followed. Limited evidence supports the use of growth promoting implants in calves less than 30-45 days of age.

The use of cattle implants which have the ability to improve daily gain and feed efficiency, especially in times of elevated feed costs, deserves serious consideration by cattlemen during all phases of production. When used properly and in a well-planned management program, implants have little impact on future quality grade and ultimately meat quality. In addition, producer return on investment levels of 10 : 1 are common.