3 year old tabby losing weight and is just not himself

we have had our 3.4 year tabby, Texas, since he was 3 months old. We adopted him from the sheltr and he was quite sickly at first with diarhhea and after 6+ months he came around andd got up to 16lbs and heavy obviously. He begged for food ath the dinner table, ate any scraps he found on the floor. We put him on Royal Canin food to help lose some weight but it back fired and after not quite a month he lost 5 lbs, his eyes look inset, his back is boney to the touch and his face looks so tiny. I know we wanted him to lose weight but he is just not himself. He doesn't join us at the dinner table, he doesnt beg for food. We have a 6 month old lab pup in our home that chases him and the other cat as well as our 3 year old puggle. But the pup has done this since we got her 4 months ago. We put our 14 year old PitBull down last June who Texas was extremely close to and looked to as a mother figure when we first got him. He would curl up on Peaches back and then in around her stomach as he grew. He didn't really mourn, our puggle was showed more sadness then Texas. Could any of this be his problem just delayed reaction sort of? or could it be something more serious and a vet visit is needed.? Thank you for your time.

Answer
Hi
No this is not normal and i don't think it is a delayed response. Cats have a very strong survival instinct and so not eating is a definite sign that something is wrong. If he is eating but still losing weight then their are conditions which can make this happen such as diabetes or a heart problem (don't worry most things are treatable). The only way to discover the cause is for a blood test to be carried out by the vet. So yes i do think a trip to the vet would be a good idea at this stage.

Don't worry but do take him to see a vet as soon as you can.

best wishes Kate

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