I live on a farm and for the past week we have had a stray cat hanging around. It got really cold last week (-30!) so the cat has been living in one of our steel buildings. I noticed it is VERY skinny - almost nothing left of it. So I started giving it dry and canned cat food as well as water. It is eating really well and was obviously very hungry. We made a little house for it. Just a wood box with blankets and a piece of carpet for the roof. The cat is VERY friendly and affectionate... lots of purring and meowing. However... I can tuck it into its blankets and it won't move for most of the day. It is slowly starting to put some weight back on but has a long way to go. We will keep this cat but it will remain an outside cat. Anything else I should be doing with it right now as it has been so malnourished? Anything else to make its house warmer? Is it normal for it to spend so much time cuddled up in its bed?

It will pick up weight, and cats sleep a lot usually up to 20 hours a day. Esp when it is cold.
Is it male or female? Most Cats do not go into heat until Jan and February so you have awhile to get it spayed.
You may want to consider getting it shots, rabies esp. since it is on the outside and deworming it. Cats that eat rodents are more likely to have worms, this can also cause them to be skinny and have a potbellied appearance.
Thank you for taking this cat in

We don't know yet if the cat is male or female. It has long hair and is very fluffy so we can't see. We didn't want to disturb the cat too much at this point. I am guessing that since we can't see - that it is probably female. This is my first time ever taking care of a cat and ever really being around one. Quite often we have had cats wonder into our yard for a couple days and then move along. Once this cat is back to being healthy it may wonder off as well - so we don't plan on taking it to the vet at this point. If it ends up sticking around a few months then we might. Isn't there anything we can buy over-the-counter for worms just in case? What about milk? I have heard this is bad for cats but I know people give it to their cats as a treat.

I know people who buy their cats kitty milk, but I never had, other than for stray kittens that I have found. If it were me I probably would not do it... you do not want to put her/him off drinking water, cats really do not drink that much water as it is so they really need the water to clear out their system. The more milk the less water they would consume is my thinking.
You have quite few months to get her/spayed neutered. Before mating season. If you don't then more than likely it will take off in search of a mate if it is a male... if it is a female your place will have quite a few male visitors looking for love... I believe she can mate with each one until her heat cycle is over and have kittens by them all.

If you are planning on keeping this cat as an outdoor cat, I think that you need to provide it better shelter, especially if it gets to -30 where you live. If the box you have is inside the steel building, or that building is heated, then you are probably OK. Otherwise, you may want to take a look at IndyFeral - Outdoor Cat Shelters

Here's advice on building a shelter for one cat (since most of the links are to colonies with multiple cats, I thought this might be useful for you): An adequate shelter for one cat can be made from a simple Styrofoam cooler available at any hardware store for about $6. Glue the lid onto the cooler, turn it upside down and cut a hole in one side (anywhere but in the middle of one of the long sides). The Styrofoam containers used to ship meat can be turned into shelters in the same way and can, depending on their size, house 3 to 4 cats. If you want to get fancy, get a large Igloo cooler and, with a jigsaw, cut a hole towards the left or right of one of the long sides. The attached lid will allow for easy cleaning.

The only thing I would change is that I wouldn't glue the top on, if it's inside the building. And add some straw inside it so the cat can burrow down into a nest and trap its body heat.

And yes, right now the cat is going to be concentrating on not using up any more energy than it has to. So eating food that you provide, and curling up to sleep in a warm place, are going to be its top priorities. The other advice the feral cat pages have is to feed kitten food, since it has more energy per ounce. You might want to consider that until the cat gets to a better weight.

The first thing I would do is take this cat to the Vet.if that's feasible for you and have it checked for leukemia and if that's negative proceed with a fecal examine to make sure parasites aren't the cause of the weight issue.It has to be healthy to receive fascinations,meaning no fever or illness.As far as sleeping a lot, cats do for most of the day since they usually hunt at night.Leukemia or anemia especially if has fleas could explain a lot.I am not a vet.but I do work for my vet/ best friend... As far as the shelter situation.. one of my friends whose husband is a vet. Had a outdoor cat that was getting on in years,had her father build a wooden box with a small opening for the cat to enter through the side and she put a heating pad on the bottom,used a hole saw to make opening for the cord and controls to be on the outside so she could turn it off and control temp.her cat slept in this house every winter and never got electrocuted and he lived to be 22.He hated indoors or he would have been in the clinic.Is possible check the cats ears for earmites and check the gum color if its gums are pale get it to the Vet.Hope this helps...

Thanks for all the great advice. Izzy's (the cat) home is in one of our buildings. Although the building is not heated it is well protected from wind. I have a wooden crate filled with cedar chips and blankets and then a roof over it with carpet and carboard. Seems to be doing the trick and keeping her warm. Last night and today she was actually out of her house walking around and seemed excited when I arrived. She came over right away and sat and let me pet and brush her. I can tell already that she is putting on weight as you can't feel her ribs as well and she no longer eats all her food when it is given to her. I checked her ears and fur and everything looks fine - no mites or flees. She does have a bit of an odour(stink) - not sure what to do about that. We do have a dog that has seemed to like cats in the past that we haven't introduced to her yet. Not sure when or how we will do that. I wouldn't want to take her to the vet and spend money on getting her fix when we aren't even sure she will stick around. So we will just wait and see on that one.

You might want to check with a vet about the cedar chips. Cats are sensitive to a compound (phenol) found in evergreens and yews, and it can kill them. Although that warning is generally associated with pine-scented cleaning solutions. I do not know if it's found in cedars, or if the concentration is low enough that it doesn't matter. A vet, humane society, or local trap/neuter/spay/release or other feral cat group in your area could probably tell you.

Since she is letting you pet her, it seems likely that she is a stray, possibly lost. You might want to see if a vet will scan her to see if she's chipped, and keep an eye out for lost cat posters. Not sure what to do about the odor. Can you describe what it smells like or where it seems to be coming from? It could just be dirt, if she was in really bad shape and not grooming. Anal glands, abscesses, organ failure, and bad teeth are other possibilities. Whether it's a big concern or a small one depends on what the cause is.

Oh how sweet. My advice is to take her to a vet ASAP!! Don't delay. It could have parasites, heartworms, aids or lukemia. If she is healthy get her spayed. The poor baby may just need some food.

Good Luck and thanks for saving her!