my brothers queen cat - lost too much weight after birth???

hey my brothers cat gave birth to 5 kittens 5 weeks ago. The cat has always been tiny in comparison to my cats and has a tiny frame. Now she has given birth she has failed to put weight back on and were unsure what we can do to help. She has decided that she doesnt enjoy adult cat food anymore and will only eat kitten food but will only eat around 2/3 what she should eat a day. She still has a belly but at the top you can see her boney structure pertruding. Is there anything you could suggest for her?? ive read they should have supplements but theyre not sold in any pet shops ive been too? Is this normal that they find it hard to regain weight? or should she be taken to the vets? As i say this question is on behalf of my brothers cat so if any further info is needed. i will do my best to answer.

Answer by kate
well it may be that she does need some extra build up food and especailly while she is nursing, if you go to my cat food page here https://www.our-happy-cat.com/cat-diet.html you will see a specail food for nursing queens. it may be that you have to buy it over the internet if your local store doesn't sell it but it may help your cat during these times. the food will probbaly contain extra nutrients to help her build up.
She should be fed separately from your kittens so that she doesn't eat their food as it probably is not as good for her.

If after trying the new food for a week or so or if she shows any further signs of illness of weakness then take her to the vets immediately. However its probably nothing to worry about and she just needs some extra nutrition during these first weeks. Good luck kate

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