Posted: April 27, 2009, 5:00 a.m. EDT
Q: My guinea pig has bald patches on both of her sides. Her veterinarian says there are no parasites and there aren't any other physical reasons for her baldness. When this first occurred, she was in a very small cage and she probably rubbed the hair off of her sides. But now I have her in a much larger cage, and rubbing isn't an issue, except when she pushes her house around. Should I use a dog shampoo with pyrethrins, just in case there are parasites? I have a dog that will most likely bring fleas into the house. If I may, I'd like to use the flea shampoo.
A: Never use a shampoo with any sort of insecticide on a guinea pig. Guinea pigs are very sensitive to these chemicals and can die. What is very safe for a dog or cat can kill a guinea pig. I recommend that you revisit your veterinarian, or get a second opinion.
In female guinea pigs, a bald patch on one but usually both sides of the abdomen is a sign of ovarian disease. Usually, these are cysts, which can be treated. Once they are treated, the hair regrows. Rarely, the ovary has cancer, which causes these same signs. If that is the case, surgery is necessary to remove the diseased ovary.
Because a veterinarian can’t tell from just looking at the guinea pig if it is a cyst or cancer, he or she may recommend some testing. I encourage you to get another opinion as soon as possible in case it is either of these diseases.
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