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Ralgro Implants (Cattle)

This page contains information on Ralgro Implants (Cattle) for veterinary use.
The information provided typically includes the following:
  • Ralgro Implants (Cattle) Indications
  • Warnings and cautions for Ralgro Implants (Cattle)
  • Direction and dosage information for Ralgro Implants (Cattle)

Ralgro Implants (cattle)

This treatment applies to the following species:
Manufacturer: Schering-Plough

NADA 38-233, Approved by FDA


Zeranol, the active drug in RALGRO, is a derivative of resorcylic acid lactone fermentation product. The RALGRO implant provides a management tool to produce increased rate of weight gain and greater feed efficiency in all classes of beef cattle.

Zeranol is an anabolic agent that has a positive influence on the dynamic state of protein metabolism in the animal. Studies indicate that one mode of action of zeranol is stimulation of the pituitary gland to produce increased amounts of somatotrophin. Implanted animals can be expected to gain 10% faster and improve feed conversion 8% over nonimplanted animals.

Ralgro Implants (Cattle) Indications

Used to increase the rate of weight gain and improve feed conversion in suckling beef calves, including replacement heifers between one month of age and weaning, weaned beef calves, growing beef cattle, feedlot steers and feedlot heifers.

Ralgro Implants (Cattle) Dosage And Administration

The dose for all classes of beef cattle is 36 mg (three 12 mg pellets). The implant site is subcutaneous, between the skin and cartilage on the back side of the ear and below the midline of the ear. The implant must not be placed closer to the head than the edge of the auricular cartilage ring furthest from the head. The location for insertion of the needle is a point toward the tip of the ear and at least a needle length away from the intended deposition site. Care should be taken to avoid injuring the major blood vessels or cartilage of the ear. Squeeze the trigger of the RALOGUN® to deliver a full dose of RALGRO. Keep the trigger depressed while withdrawing the needle to be sure that the RALGRO implants stay in place.


Not for use in breeding herd replacements or lactating dairy animals. Edema of the vulva and udder, teat elongation, rectal and vaginal prolapse, and signs of estrus may occur when heifers are implanted. Delayed testicular development may occur in young males. To avoid difficulty in castration, young males should be castrated at the time of implanting.

How Supplied

RALGRO is packaged in cartridges specially designed to fit the easy-to-use RALOGUN pellet injector. Each cartridge contains 24 doses; each dose or chamber of the cartridge contains three 12-mg pellets (one dose). Each cartridge is individually wrapped. Ten cartridges are packed in one carton (240 doses). Two cartons are packed in one shipper unit (240 doses). Also available in single cartridge boxes.

Nac No.

556 MORRIS AVE., SUMMIT, NJ, 07901
Telephone:   908-629-3490
Order Desk:   800-648-2118
Fax:   908-629-3306
Customer Service:   800-521-5767
Every effort has been made to ensure the accuracy of the Ralgro Implants (Cattle) information published above. However, it remains the responsibility of the readers to familiarize themselves with the product information contained on the US product label or package insert.

Copyright © 2018 North American Compendiums. Updated: 2018-04-26