Thank you for your patience. There are quite a few things that could be going on here with Ashes to put him off food, including anything from dental or oral pain, early gastroenteritis, an internal organ issue, or even a toxicity or poisoning. You are going to have to keep a close eye on your boy and continue to try to encourage him to eat. Hopefully he is drinking water with no issue, and if not, the worry is that he could very quickly become dehydrated, so do continue to encourage him.
Given his age, there is every chance your boy has bad dental disease or some oral pain for another reason. This would be even more likely if he seems to want to eat, but doesn't pick up and chew the food, or attempts to eat, but spits the food out. You could certainly try some wet cat food for the next few days to see if you can convince them. Heating this wet food up for 3 - 4 seconds in the microwave can help to give it more of an aroma as well. Try several different cat foods with different key protein sources (fish vs chicken vs beef for example). If you have noticed him drinking more water than usual, then we need to consider potential issues like kidney disease and diabetes here as well, so if this is the case, do get him seen tomorrow by your local vet if you can. For now, please keep an eye your boy's mucus membranes, capillary refill time and respiratory rate tonight as follows (do be careful that your boy doesn't try to bite you):
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 or open mouth breathing at all tonight, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
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