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Ask the Veterinarian/Cat losing weight


We adopted two cats from the same litter over a year ago, and one of the cats, aged just older than one year, started losing weight. His little teeth between the fangs were slightly crooked and it took him a while to eat. He also lost a lot of weight. We believed these to be related and took him to the vets and they said it was probably worms and that the front teeth between the fangs at the bottom wouldnt affect him too much. They gave us worming treatment and sent us on our way.
We gave him the treatment but he still didn't get better and continued to lose weight. We booked another vet appointment but the next day he went out and never came back. We put up posters and looked for him but never found him, assuming he went away to die as I read that this is something cats do.

This was probably six months ago, and his sister is nearly two. She is having a similar problem but her teeth are normal. She is losing weight but we are certain she eats and drinks. She pees and pops inside on our floorfloor (her brother does this too) despite knowing how to use the cat flap and her back is always hunched (it has been this way for a long time) and her back knees face inward into each other. She is very light and boney and we are scared she will have the same fate as her brother. We did the same with her and again, treated her for worms. We believe she left her mother at a very young age (too young). I hope this is enough information, thank you very much for taking the time to read this. I appreciate any advice and information!

Thank you,

Hi Amanda,
thanks for all the information, I will try to help as best I can, but I might ask a few more questions:
What sort of food are you feeding your little girl?
Are you doing the worming every 3 months?
Do you think she is a hunter?
Does the faeces look well-formed, or is it soft and smelly?
Does she always eat, or is she fussy with food?

There are lots of things that can cause weight loss in cats, from infectious causes like viruses, protozoa (giardia, tritrichomonas, coccidia), bacterial diseases, as well as inflammatory bowel disease, food intolerances or allergies, liver disease and pancreatitis.

When was the last time you took her to the vet for the worming? If I was your vet I would probably try worming her first, but if that did not improve her health, I would do some more tests or put her on a special food to see if she responds to that.


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Eloise Bright


I am a vet with a special interest in dermatology, particularly allergic dogs and cats, behaviour and acupuncture. I work mainly with dogs and cats. If you are wondering why your pet is still itchy, despite good flea control, or why your dog licks his feet, I may be able to give you some solutions. I'm currently very passionate about behaviour and am doing some further education in this area. So if you have a troubling behaviour with your dog or cat, such as barking, leash reactivity, anxiety or a dog who is a little wild and difficult to control, I may be able to help you with some solutions.


I work in an area of Sydney where we see lots of allergic pets. I think behaviour problems are very common and I help a number of owners find solutions that will restore peace to them and their pets. Currently I enjoy answering questions, providing advice and writing pet care articles for

I graduated as a vet from Sydney Uni in 2006 and have since been completing my Masters in Small Animal Practice and am also updating my skills with a behaviour course through Sydney Uni.

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