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Guinea Pigs/Guinea pig, loosing weight


Hello I have lost 2 weeks ago an 8+year old female guinea pig! she detiorated over 3 weeks, loosing use of her back legs, but eventually gave up after a determined fight. I have 4 other guineas, one is a 3 year old neutered male who was soul mates with the deceased female.
I noticed he was loosing weight also 5 weeks ago so started weighing him also whilst I was caring for the old one.
He had a dose of antibiotics as I thought he had a bit of a wheezy noise, and vet thought it was best to try this. That was 4 weeks ago.
So over the last 4 weeks he has gone from 810g to 660g.
In the middle of this time the old female died.
Last week I took him to vet to get some rabbit rescue food to syringe feed him. But his weight has not really gained at all.
I also noticed he has a large soft lump in his right abdomen, and also a small hard pea sized lump in left abdomen, but he doesn't't seem in pain from feeling these.
He is still eating and always drinks a lot of water.
But obviously he is not eating a lot.
The vet thought that removing lumps is probably best avoided at the moment.
To keep an eye on situation.
I don't know how long to leave him, with loosing weight, and how much of that could be stress or sadness.
Also how dangerous to remove lumps in that area and how related to his weight loss. I know he is still passing small solid droppings, which look normal.
Do you have any suggestions on any action, he just seems quiet, and so thin, other general appearance is still ok.
Thank you.

Your vet is right, you don't want to put any animal under the stress of surgery when they are not in to shape.

I am not familiar with the rabbit rescue food but you need to be careful with any rabbit food or supplement that they don't have any antibiotics in them. Generally speaking guinea pigs don't tolerate antibiotics. If antibiotics are indicated they should be a sulfa based med such as Bactrim or Baytril. They absolutely cannot tolerate any form of Penicillin.

What happens with the penicillin is a destruction of the natural flora in the gut that is necessary for digestion. The result is a severe belly ache and a secondary infection that depresses the appetite, thus causing weight loss. I am assuming your vet is aware of this and did not prescribe any pcn.

8 years is a very old pig comparable to a 98 yr old human. The sow simply died of old age. At 3 we wouldn't consider age related issues. Weight loss is often caused b a dental malocclusion aka overgrown teeth. Cavy teeth never stop growing so they need something to chew on to help keep them properly worn, otherwise they begin to decline from starvation. This would not have anything to do with the lumps that has now has.

Guinea pigs are prone to certain cancers. That's possibly what it going on with him. In this deteriorate state he would not survive surgery to remove them. If the vet is able to do it an ultrasound might be more diagnostic. He may be able to see the nature of these masses.

Unfortunately guinea pigs do not show us they are I'll until it's too late. At this point his care is paliative, or just for the purpose of keeping him alive in the hopes that he will turn around and stabilize.

If it turns out that the rabbit rescue contains penicillin you an use a product called Critical Care which is designed for guinea pigs. If that is not available I have used baby formula with a soy base.

I know this isn't terribly encouraging, but unfortunately your little guy is very I'll and may not turn around.. Please don't feel that it is anything you have done. These little animals are difficult at best to treat when ill, typically because they are sicker than we think by the time we realize their is a problem.

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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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