Kitten Needs to Gain Weight

Hello,

I have a couple foster kittens. I have had them for around 80 days now and they came to me at 9 days old, so they are about 3 months old. Here is the problem, there are five of them. Three have gone back to the shelter a while back when they hit two pounds because that is when they could be spayed and neutered... but I still have two. One of the boys just made it to two pounds but the other wasn't anywhere near and so they sent the two home so there wouldn't be one all alone. (Though he could have stayed with the other fosters... anyway)

He is three months old and not even two pounds! He should be around three pounds now according to what vets have told me.

He has been the the vet MANY TIMES! There is NOTHING wrong with him. He is completely healthy according to my vet and the shelters vet. We dealt with a severe case of diarrhea and vomiting at one point. Just couldn't stop it in the litter, even though they were on the same food the entire time! It was very weird, never have had this issue before. So they struggled with weight gain obviously at that point, but the rest of the litter is doing great. Just this one little guy that isn't making it to two pounds! He is active and everything (probably the most active of the bunch).

I need to fatten him up, you can feel his bones and I can't stand it. I feed him wet food mixed with dry food three times a day. I leave hard food down at all times (I know not everyone here likes hard food but unfortunately because he is a foster, I don't get to decide what he eats once he goes back to the shelter and I won't put him on something only to have it changed when he gets to the shelter because he is very picky.) 

I bought Nutri-Cal and that seemed to help for a bit, but now... not so much. 

Any advice would be great.

Thanks! 

he is adorable....

perhaps it is the fact that he is the most active of them all that is causing him to not gain weight. 

he might also have been the runt or the smallest of the litter, and these remain smaller than their brothers and sisters. 

he will eventually grow but it might take a bit longer.   

you can try feeding some home cooked meals, some say they help add protein more, maybe one of the 3 meals a day can include one of these: 

A Little Home Cooking Can Be Helpful

There may be some good additions to your cat's diet in your own pantry or refrigerator. Scrambled eggs without butter or seasonings are a great protein and fat source, and most cats find eggs very tasty. Plain yogurt also is a healthy addition, and provides good probiotics to help your cat's digestion. Canned sardines or mackerel also have a good level of healthy protein and fat, and your cat may be unable to resist. Be sure to get them packed in water with no salt, rather than packed in oil or other flavorings. It's not a good idea to switch your cat completely to home cooked food until you do enough research to be sure you are providing a balanced diet. 

That's the weird thing though! He wasn't the runt, he was the biggest when I got him at 9 days old... by far!! The runt is now the biggest by far She was the first to hit two pounds and she is well over 400 grams above the next closest! 

The guy I need to fatten up is Hank, I was going to name him Pumba he was so big compared to the others! He was very attached to his mom, the shelter requires the mom goes back to dry up and be spayed and I think that affected him negatively. I think he could have used more time with her. He wasn't eating hard food when she left... he was hardly eating wet food! 

I will try all your suggestions, thank you so much!

i wish i was like hank not gaining weight 

well i did see that kittens suffer from separation anxiety when leaving their mom so it is possible that this is part of it. 

might also be that Hank is too active, running around and playing, so maybe u can pet him so he becomes basically tired and doesn't want to run around any more and feeding him. 

we have a stray cat that was thin and malnutritioned and is now our outdoor cat, but we fed him sardines and chicken and now he is pretty fat, i remember it took a while about 2 weeks till he got proper, but the point is, sardines work, i hope they work for you,