Why did my friend's dog pass away suddenly with no obvious cause?

I'm very sorry your friends lost their dog so suddenly! Without seeing him in person, I can't say for certain what caused him to pass away, but the symptoms you describe sound like he was extremely ill. He could have had a systemic illness not related to his hyperthyroidism that caused him to pass away. The only way to know for certain is to have a necropsy (an autopsy for animals) done on him to determine his cause of again. Again, I'm sorry for the sudden loss of your friend's dog.

First off, I'm so very sorry that you lost DJ suddenly. Please accept my condolences for your loss. Unfortunately without seeing him in person, I cannot say what caused him to pass away. It could be he got into something toxic, he could have had heart disease, or it could be he had cancer causing him to pass away. I wish I could give you a definitive answer, and I feel badly that I cannot. Again, I'm sorry for your loss.

I'm very sorry Lizzy passed away today! Without seeing her in person, I can't say what caused her to pass away, but common causes of death in senior dogs include heart disease, organ failure, and cancer. If you want to know why she passed, you could bring her into the vet for a necropsy (an autopsy for dogs). Again, I'm very sorry for your loss.

I am so deeply sorry for your loss, my thoughts are with you in this difficult time. It is of course difficult to know precisely what happened to Daisy without examining her, however, I would be concerned about two possible conditions. Bloat which is when the stomach becomes englarged and may rotate. This causes the blood vessels to constrict and affects blood flow to and from the heart. It is common in large barrel chested dogs. Another possibility is A foreign body obstruction, which occurs when something becomes lodged and Blocks the gastrointestinal tract, the bloackage can be complete and cause a rupture. Again it is difficult for me to know what could have caused Daisy to pass. If you need to know definitively, a local veterinarian may be able to perform an autopsy. Sending my deepest sympathies to you.

Oh no, how horrible for you to experience! I am so sorry for your loss! She could have had heart problems, cancer, liver failure, or possibly something toxic you didn't realize Bella got into during the day. Without seeing her in person, I can't say for certain what caused her to pass away, but I do recommend taking her into a vet for a necropsy. This is an autopsy for dogs, and it may give you some answers on what caused her to suddenly pass away. Again, I am so very sorry for your loss, please accept my condolences :-(

I'm sorry to hear that you're having this problem! Unfortunately, it's really not possible to know what's causing this without more information, since acting lethargic and not eating are very vague symptoms that could be caused by almost any kind of illness. If any of the dogs have had lab work, x-rays, or other testing done, it would be helpful to know what the results were in order to give some possibilities. For a definitive diagnosis, the best option would be to have an autopsy (called a necropsy in animals) performed on one of the dogs who passed away.

I'm so sorry to hear about the loss of your dog. There are many different problems that could cause those symptoms, so unfortunately an autopsy (called a necropsy in animals) would be the only way to know for sure. Some possible causes would include some type of toxicity (such as antifreeze or rat poison), an illness such as kidney or liver failure, or some type of cancer. Your vet could do a necropsy or direct you to a pathologist for more advanced testing if you want to try and determine a specific cause of death.