Whatever it is, use it, unless you are providing for an organic or 'all-natural' market. Implants increase average daily gains by 10 to 15 percent and improve feed efficiency 5 to 10 percent. Fike, who serves northwest Iowa and is a member of the Iowa Beef Center at ISU, recently conducted studies on various implant strategies as well as Encore, a new long-term implant made by Ivy Labs and distributed by Vet Life. Fike recommended that all beef producers ask their local beef field specialists to prescribe implants. Other implants contain estrogen or estrogen-like products that act on the anterior pituitary to release more growth hormone, making the animal grow faster and convert feed more efficiently.
Some implants contain a combination of the two.
If the cattle have large frames and are heavily muscled and lean, a combination of TBA and estrogen may be a better choice than a straight TBA implant. Fike also suggested considering carcass results when selecting implants. Once an implant has been selected, producers need to consider strategy. For example, if producers use a TBA implant, the cattle may not grade well if the implant is less than 100 days prior to slaughter. However, to say that implants have a negative effect on quality grades in general is a false statement.