Immune Response: The body's reaction to infection.

Immunization: To produce immunity in, as by inoculation.

Imported Semen: Frozen semen that is imported from another country.

In Whelp: Pregnant.

Inbreeding: The mating of two closely related dogs of the same breed.

Incisors: The six upper and six lower front teeth between the canines. The point of contact forms the bite.

Incontinence: The inability to control excretory functions.

Incubation Period: The period between infection and the appearance of symptoms of a disease.

Inflammation: A localized protective reaction of tissue to irritation, injury, or infection, characterized by pain, redness, swelling, and sometimes loss of function.

Inherited: To receive (a characteristic) from one's parents by genetic transmission.

Injection: Something that is injected, especially a dose of liquid medicine injected into the body.

Interbreeding: The breeding of dogs of different breeds.

Internal Parasites: One celled protozoan, larvae and worms that survive by living off the host animal's meals or blood.

Iris: The colored membrane surrounding the pupil of the eye.

Irish Setter: Any of a breed of setters having a silky reddish-brown or red and white coat.

Isabella: Usually used to describe Doberman Pinschers, this color is similar to fawn or light bay, but has more saturation and brilliance (similar to a bay-colored horse). Color definitions may vary by breed. Always check the breed standard for the definitive color description.