Steroid Implant Placement in Beef Cattle: Correct Anatomic Site

For growth-promoting steroid implants in beef cattle, the only approved and correct placement site is subcutaneously at the base of the ear (ear implant site).

Regulatory and Technical Details

• FDA/EPA/USDA requirement: All approved implants (Ralgro, Synovex, Revalor, Component, Compudose, etc.) specify "subcutaneous in the ear only."
• Anatomy: Between skin and cartilage of the middle third of the ear (not tail head, not neck, not elsewhere).
• Technique: Needle inserted bevel-up, parallel to ear surface; implant deposited in subcutaneous plane; no suture needed.
• Sanitation: Clean needle, disinfect site (chlorhexidine/alcohol), avoid manure-contaminated ears.

Why NOT Tail Head or Other Sites

• Illegal/off-label: Violates FDA approval conditions; residues may not clear per withdrawal times.
• Food safety: Non-approved sites → unpredictable absorption → violative residues in meat.
• Animal welfare: Tail head has thicker skin, more nerves/vessels → pain, infection, nerve damage risk.
• Economic: Carcass trim losses at slaughter if implants migrate or cause lesions.
• Audit compliance: QSA, BQA, packer audits verify ear-only placement.

Common Implant Types

• Estrogenic (zeranol/Ralgro)
• Androgenic (trenbolone acetate/TBA)
• Combination (estradiol + TBA: Revalor, Synovex Choice)
• Sustained-release (Compudose: estradiol silicone)

Bottom line: Ear only. Every implant, every animal, every time. Train all personnel; document placement.