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Guinea Pigs/Guinea Pig breeding boar


I was given a GP boar who is around 1.5 years old. Was told he never  has been able to produce offspring. I have him running with my 3 yr old sow (has had 2 litters in past)
On examining him today I noticed he didn't protrude his penis. my other boars do this when genitally pressed.
Could this be the problem? Is their a known genetic disorder in male GP's?
sorry for the strange question, he is an outstanding boar (pedigree) and would love a litter from him, but he may not have the tools required? (can feel both testes and behaves normally) was over weight when I got him, is currently on a diet.

It's not likely there's a genetic disorder. There may be a testosterone problem that's keeping him from breeding. Of course that's not something we're going to spend the time and money to determine and treat. If he doesn't at least purr and rumblestrut at a sow when he is in the cage with her that could be the problem.

I've had boars that were lazy and didn't show interest in the sows. I found that tossing them in with at least two sows seemed to perk up the passion.

I wouldn't put him on a diet. Unlike rabbits guinea pigs don't need to be kept to a desired weight level.

It's frustrating when you're trying to get them to get down to business and they seem to lack the necessary spunk. Rabbits are spontaneous ovulators and putting the back end of a doe to the front end of a buck will cause her to immediately come into heat and get bred. Cavies just don't follow those rules.  They can be housed together for weeks or months before any action takes place.

If he's just not showing any interest at all you may have to find another boar.  

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Pat VanAllen


As is sometimes the case, people in urgent need of information have a higher degree of expectation than those of us as experts are able to give. The experts on this site do their best to give the most accurate and responsible answers possible. We ask that you remember that it is not our intention nor place to criticize the professional advice given by your veterinarian, nor is it appropriate for us to comment on the correctness of a diagnosis made by a licensed physician. Our knowledge is experience based. Although many years of breeding and showing cavies gives me a wealth of experience it cannot change the fact that we as experts are not veterinarians and therefore may occasionally have to reject questions that appear to be asking us to criticize advice given by the licensed professional. Having raised and exhibited cavies for many years I have extensive experience in cavy care and husbandry. I currently have an active breeding program for pedigreed show animals but do not encourage backyard breeding for inexperienced owners. Although I don't encourage breeding for fun I'm always happy to answer any questions from an owner who is in sincere need of help. Pet owners wanting to breed should understand that even experienced breeders have litter losses. The mortality rate is high in cavies. The chance for losing both sow and pups is always present, even with experience. Although this is a site for experts to assist owners, there is no expert in any field who has all the answers. The wisest thing a good expert can know is their limitations. Not having an answer does not diminish one's ability or knowledge. It simply shows that we recognize our limitations and operate within them.


Raised and shown cavies for many years, having aquired my first cavies in the early 1970's as pets. My caviary currently handles 65 + animals in two different breeds and several varieties. Having been in the health care industry as a licensed nurse for 35 years I have hands on experience with care and needs in both humans and cavies. Member of American Rabbit Breeders Association and American Cavy Breeders Association.

Awarded Lifetime Membership in of one of the oldest cavy clubs in the United States, on whose Board I served as Sec/Treas for six years and currently serving as President. Also editor/publisher of the club's quarterly newsletter. We are strong supporters of our youth exhibitors, most of whom are 4H members who are working on cavy projects. Through these projects they become good responsible citizens. We deal with all aspects of showing, breeding, caring for and sharing experiences in the fancy. The cavy fancy is not a new one but in some areas is still relatively unknown. Our goal is to inspire interest in high quality, responsible breeding to improve the species, not just the reproduction of guinea pigs. Our job is to educate owners to help them make the right decisions and choices in the care of their cavies.

Graduate in nursing. Certified in emergency medicine.

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