Thank you for your prompt reply. As you can probably imagine, there are quite a number of possible causes for Rascals' symptoms here, but because he is an older boy, we do have to consider issues that are more common in older dogs including potentially an oral mass, an internal organ issue or even an endocrine problem like diabetes. If you haven't noticed any other symptoms at all other than weight loss and inappetance, then it becomes very hard to narrow down the options without your boy having a full physical exam and blood tests to check his internal organ function. Typically if these symptoms were due to an oral problem, then we would generally also notice some drooling, pawing at the mouth, or at least a little bit of interest in food and an attempt at eating, rather than simply not being interested in anything at all.
While it is great that he is drinking, urinating and defecating as per normal, the fast degree of weight loss is one of the main concerns here. The more weight loss he has in the next few days, the more lean muscle he will be losing - and the harder that is to recover from. It sounds like you have probably tried every diet and piece of human food under the sun. For this reason, the next best step here is to get Rascal straight down to your local vet for a full physical exam, a full geriatric blood profile and for the nursing staff to attempt syringe feeding him. If he refuses syringe feeding, then a feeding tube needs to be placed asap. While these sound dramatic, they are actually very well tolerated and will allow your boy to meet his daily caloric requirements to help stop any further weight and muscle loss here. This it the most important next step, as his prognosis is really going to diminish quite quickly if he continues to lose weight at the current rate.
A full physical exam may highlight the issue, however it is more than likely that further diagnostics will be needed. The best place to start here is with a full geriatric blood test given your boy's age. This will help to rule out a primary internal organ issue as well as an endocrine problem such as diabetes, cushings disease or addisons' disease (to name a few). Further diagnostics may potentially be necessary including an xray or abdominal ultrasound depending on how the physical exam and blood tests go.
If your local vet is still open, then there really is no reason to wait any longer. If you can get an appointment to follow up on this right away, please do. If they are now closed, then definitely arrange an appointment for first thing tomorrow morning. Hopefully he is absolutely fine right now (other than not wanting to eat!), but do keep an eye on his mucus membranes, capillary refill time and respiratory rate as follows:
Mucus membranes - flip his lip and look at the color of his gums. They should maintain a nice salmon pink color. Get him to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on his gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if he is continuously panting throughout the night, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
Best of luck with Rascal and as above, please do follow up with your local vet today if you can. I hope all of the above makes sense? Please let me know if you have any other questions. My goal is to provide you with excellent service – if you feel you have gotten anything less, please reply back. I am happy to address follow-up questions. Thank you for your business and I hope to work with you again soon!
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