Final answer:
A subcutaneous injection is a method of administering medication or fluids directly under the skin, usually along the back of the neck or between the shoulder blades.
Step-by-step explanation:
A subcutaneous injection is a method of administering medication or fluids directly under the skin, into the fat layer. To perform a subcutaneous injection on a pet, you would typically place the needle just below the skin, usually along the back of the neck or between the shoulder blades. This area is commonly used because it is easily accessible and has a good blood supply, allowing for efficient absorption of the injected substance.