Why is my young male rat biting and acting aggressive? Is it hormones?

It is, unfortunately, very common for male rats to begin fighting as they get closer to sexual maturity. Your rats are getting to be that age, so that may be contributing to the scuffling that you are seeing. There are a few things that you can try - one is to completely separate them from one another. This can be complicated as you will need to have three separate enclosures. Sometimes there is only one aggressor - if you know that one of the rats is the bully (usually the one that has no injuries), you can also try to separate that one and leave the other two together. Unfortunately, sometimes this can then lead to the other two fighting (so it doesn't always work). Another alternative is to get them castrated. I am not sure what the comfort level of the veterinarians in your area is with rats, but this would remove the hormone component of things. I hope that gives you a place to start, and thanks for using Petco Pet Education Center, formerly Petcoach.

Thanks for reaching out about Thor. Either are possible, and a veterinary visit is recommended to assess and provide a diagnostic/treatment plan. Is he still eating, drinking, defecating and urinating? Dragging the ventral abdomen could be discomfort from a urinary tract infection/obstruction (possible calculi), constipation or other problem. Good luck.

Thanks for reaching out about your rats. Sexual maturity and the present of testosterone will present a stronger urine. Urinary tract infections will also result in similar smells but would be uncommon in multiple animals at the same time. Can you separate the animals and determine who's urine is odorous? Castration can lower the smell. Good luck.

Thanks for reaching out about Cream. Sounds as if she is cage protective. Spaying her might calm her down. Continue to work with her, allow her to come out of the cage on her own and then handling. Hopefully this will allow her to acclimate to your presence. Good luck.

Hi there and thanks for using Petco Pet Education Center, formerly Petcoach! Usually aggression in our pets can be altered a bit by removing excess testosterone with neutering. While it is not impossible he is lonely-likely he is frustrated with the removal of his mates each time. Neutering may help with his need for female attention as well as curbing unwanted aggression due to excess testosterone. I hope this helps!

Thanks for reaching out about Mr. Magoo. It is unusual for rabbits who are castrated to become aggressive after living together for some time. Environmental stresses can shift hierarchies and start aggressions. Adrenal tumors can produce testosterone and lead to aggression. Not all rabbits get along, forever and they might have to be separated. An examination with a veterinarian with experience in rabbit could probably help you. Good luck.

Hello! I would recommend having all male pet rats neutered. The surgery for neutering male rats is easier and less invasive than in female rats. Intact male rats will likely fight with other male rats and mate with any females (which leads to a LOT of babies) and neither behavior is ideal for companion pets! I would suggest having Ted neutered then introducing him to a friend a couple of weeks after he has recovered from the procedure. I often urge people to try fostering when they are adding pets. This allows you to introduce the two animals and ensure they get along well before you commit to adoption. I hope this is helpful! Thanks for using Petco Pet Education Center, formerly Petcoach!