Which statement best describes the reproductive pattern of guinea pigs?

• A. Induced ovulators.
• B. Spontaneous ovulators.
• C. Seasonal breeders.
• D. Always require breeding to ovulate.

Answer: (B)

Guinea pigs ovulate as part of a regular reproductive cycle, not as a direct result of mating. This means ovulation occurs spontaneously on a schedule, so conception can occur if mating happens around that time, but the act of copulation is not needed to trigger ovulation itself. In practice, they have a defined estrous cycle—roughly every couple of weeks—and the female’s physiology releases an egg without requiring a male’s stimulation. This is different from species that are induced ovulators, where mating itself triggers ovulation, or from seasonal breeders that only cycle during certain times of the year. In captivity, guinea pigs can cycle year-round, so they don’t rely on a breeding season. The idea that they always need mating to ovulate is incorrect because the ovulation occurs independently of mating in this species.