Which tool is specifically used to inject growth hormone into animals?

The implant gun is specifically designed for injecting growth hormones, typically in the form of implants, into animals. This tool allows for precise and controlled insertion, ensuring that the hormone is delivered directly under the skin or into specific tissues. This method is commonly used in livestock production to promote growth and improve feed efficiency. The design of the implant gun facilitates a quick and safe procedure, minimizing stress on the animal and the risk of injury.

In contrast, the other tools listed serve different purposes. A hose bib is a fitting for connecting a water hose to a water supply, lag screws are used for fastening materials together, and long nose pliers are a general-purpose hand tool used for gripping and manipulating objects. None of these tools are intended for hormone injection, highlighting the specialized function of the implant gun in this context.