Hormone | Formb | Dose | Duration of Effect (days) | Growth Response | Potential Adverse Effects |
---|---|---|---|---|---|
Estradiol + progesterone | Pellet | 20 mg estradiol benzoate + 200 mg progesterone (steers) | 90–120 | 10%–15% | Transient increase in sexual behavior Udder development Vaginal and rectal prolapse Ventral edema |
10 mg estradiol benzoate + 100 mg progesterone (suckling calves ≤ 400 lb and > 45 days old)c | 100–120 | 3%–5% | Transient increase in sexual behavior Udder development Vaginal and rectal prolapse Ventral edema | ||
Estradiol + testosterone | Pellet | 20 mg estradiol benzoate + 200 mg testosterone propionate (heifers) | 90–120 | 5%–15% | Transient increase in sexual behavior Udder development Vaginal and rectal prolapse Ventral edema |
Estradiol | Silastic rubber | 44 mg estradiol (steers and heifers) | 400 | 10%–15% | Transient increase in sexual behavior Udder development Vaginal and rectal prolapse Ventral edema |
26 mg estradiol (steers and heifers) | 200 | 10%–15% | Transient increase in sexual behavior Udder development Vaginal and rectal prolapse Ventral edema | ||
Polylactic acid | 28 mg estradiol (steers) | 365 | 10%–15% | Transient increase in sexual behavior Udder development Vaginal and rectal prolapse Ventral edema | |
a Individual product labeling should be consulted for specific purposes and dosages in food-producing animals. b Implants must be placed subcutaneously between the ear cartilage and skin to comply with label instructions so that consumption of residues may be avoided. c The FDA recognizes two subsets of animals within the beef cattle calfhood (suckling) phase: (1) < 2 months old and (2) ≥ 2 months old. US Food and Drug Administration, Classes of Major Food-Producing Animals for New Animal Drug Applications. Accessed November 17, 2023. |