My feral cat is suddenly skinny and letting me pet him. What's wrong?

Hello. Weight loss of that amount is, unfortunately, going to require some investigation. If the cat’s feeding routine has basically remained unchanged, he has been dewormed....then we need to be looking for other, more serious problems. A thorough physical exam, bloodwork and possibly x-rays. He will likely need sedation for all of this, so presenting him to the vet in a humane trap that he can be sedated while still in the trap is the safest method for all involved. Reasons for dramatic weight loss could include diabetes, intestinal diseases, kidney or liver issues, cancer, etc. I deal with feral cats all the time and it is relatively simple to sedate them through the trap in order to do any procedures necessary. Good luck

Poor Rusty! Cats can have worms even if you don't see them in the feces. Oftentimes, there are eggs in the feces, but those can only be seen with a microscope. Sudden weight loss in cats can also be caused by diabetes, kidney disease, systemic illness, infection, or injury among other causes. I would have Rusty seen by a vet asap, and bring along a sample of his feces for the vet to examine. In addition to looking at his feces, the vet can do a physical exam, blood tests, and a urinalysis to diagnose what is causing his weight loss. Once the cause of the weight loss is diagnosed, the vet can discuss treatment options with you.

How lovely of you to look after this stray! There are a number of things that could cause him to lose weight, such as intestinal worms, diabetes, kidney disease, or hyperthyroidism to name a few. He could also possibly have fleas. It's important to make sure your cats are up to date on their flea treatments and deworming treatments. As for the stray, I would take him into the SPCA if you don't want to assume financial responsibility for him. They can get him the veterinary attention he needs and find him a home. Otherwise, you can take him into the vet yourself :-)

Significant weight loss is always a concern, especially if his appetite is good. Hormonal conditions such as diabetes and thyroid disease or poor absorption and digestion of his food is possible and I would recommend a full physical and blood panel as soon as possible in order to stabilise his condition before he becomes too frail

Thank you for trying to help Forest! Because he is an outdoor cat there is a good chance he may have fleas or gastrointestinal parasites that are causing some issues. You may want to try to apply Frontline plus to the back of his neck if he will allow you to do so safely. The best option would really be to take Forest to a veterinarian for evaluation as any number of things could be causing his thin body condition and skin lesion. There may be a feral cat rescue in your area that would be willing to work with you to trap Forest, make sure he is vaccinated and neutered, and do a health exam. Good luck and I hope Forest is doing better soon!

As cats age, they can develop different diseases that can cause them to lose muscle mass and fat. By feeding a different food may not help him. He could also have intestinal parasites. If he is a feral cat I would leave him be. I would not want to risk trying to catch him in case he tries to bite. Cat bites can get very infected quickly and if he is not vaccinated for rabies you are at risk also. Thank you for using Petco Pet Education Center, formerly Petcoach.

Sudden weight loss is always a very big warning light that should not be taken lightly, it's usually a sign of an internal disease that needs to be investigated, i strongly recommend taking him to the vet in order to get it checked, he will need to have a blood test done and possibly an xray as well in order to attempt to diagnose the reason for these symptoms.