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Guinea Pigs/My Guinea Pigs Are Being Aggresive To Each Other


Hi I am new to this website so there are somethings I might not understand but whatever. So I have this guine pig named Baltazare he is almost 1 year old I got him about six month ago and saw he was kind of lonely so I decided to get a new one. So I got a new one named Melkior and he is about 3 month old. He got along prety well with Baltazare. But last FridayI noticed he had an ear infection (but he is fine know) and that same day Baltazare bit him and Melkior SQUEALED really hard! Bu know whenever I put their cages next to each other they get pretty aggresive with each other. If any of you know what I should do please answer back. thanks

Unfortunately most boars will not tolerate another boar in their space. Sometimes a very young baby will be accepted but once the baby reaches sexual maturity the testosterone begins to take over and a territorial fight begins.

You have to remember that these are herding animals. Just as with wild horses, sheep, lions, wolves, etc. there is always one alpha male and only one. As the young males are born they're allowed to stay within the herd until they begin reaching their maturity and challenge the alpha male. That's when trouble begins. They will fight to the death unless one of them gives up, at which point they are banished from the herd.

Boars are hard wired with this instinct. They reach a point when that instinct is telling them that the other is an intruder, and even though there are no sows present they react to their hormonal drive and will begin to fight. These fights can and will cause serious injuries if not actually the death of the weaker pig.

The only option you have is to separate them and keep them apart. Introducing on "neutral turf" doesn't work. Once in the cage the senior, or alpha, male will fight for his territorial rights.

The only exception to this is when you have an old boar that has past breeding age and you introduce a baby in his cage. Even then, once the baby reaches a certain point he begins to pick on the older one. It's the way nature works and we cannot change it. Even neutering doesn't always change this unless the boars were neutered before they approached their sexual maturity.  

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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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