How is the hormone estrogen, which is used as a growth stimulant, usually applied?

• A. In feed
• B. As an injection
• C. As an implant
• D. In water solutions

Answer: (C)

Estrogen, when used as a growth stimulant in livestock, is commonly administered as an implant. This method allows for a controlled release of the hormone over time, which can effectively promote growth without the need for frequent re-dosing. Implants are specifically designed to be placed subcutaneously, typically behind the ear or in the ear of cattle, which provides a consistent and sustained level of the hormone in the animal’s system. This method aids in maintaining optimal growth rates and feed efficiency.

In contrast, the other methods of application, such as administering the hormone in feed or as an injection, do not provide the same efficiency in terms of prolonged activity and may require more frequent administration. In water solutions, the hormone may not maintain consistent levels due to varying uptake by the animals and dilution. Therefore, using an implant is the most effective method for ensuring that estrogen functions as intended as a growth stimulant.