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My pet bunny is losing a lot of weight. What are the common causes?

Updated On September 23rd, 2025

Pet's info: Small Animal | Rabbit | Female | unspayed

One of my little bunnies has lost a lot of weight. What could be the cause?

2 Answers

Most Helpful Answer

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Answered By Linda G, MS, DVM

Veterinarian

Published on November 27th, 2017

Hello, sorry to hear that your bunny is unwell. There are many causes that can result in loss of appetite, & subsequent weight loss, really too many to discuss here. But diet imbalances, dental problems, infections, hairballs, gastrointestinal blockages, & cancer can all cause weight loss. Your bunny needs a hands on exam with a veterinarian to discover the reason for the weight loss, & hopefully get things turned around quickly. Thank you for using Petco Pet Education Center, formerly Petcoach.

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    Answered By Dr. Strydom, DVM

    Veterinarian

    Published on April 22nd, 2018

    Weight loss despite eating well is a bit concerning. I suggest you get Midnight to your vet for an examination. There are many different things that may be causing this. These can include increased metabolism. For example, the animal's body may start using lean muscle for energy in order to carry out its daily functions. Metabolic disorders such as organ failure or disorders associated with cancer can also bring this type of weight loss. Some other common causes may include: * Dental diseases which can make eating difficult * Dietary: not eating enough or poor quality food/hay * Gastrointestinal disorders * Neurological disorders * Metabolic/endocrine disorders Definitely use a vet that is used to treating rabbits. If you don't already have a vet you work with, I found this one in your area. Many VCA vet hospitals will provide a free first exam so that may be helpful to you. Call them to ask for details as I am not familiar with this particular hospital. ( http://www.elocalprofiles.com/m/north-hills-ca-vet/ ) Hope this helps. Best wishes.

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