How much at one feeding?

I have my kitty DeeJay who is being picky with eating her canned food right now.  I was wondering how much is too much to expect her to eat in one sitting?  I am trying to get her to gain weight, I work full time outside the home so max I could probably do 3 feedings per day.  So about how many oz would be reasonable to expect her to eat?  Right now she weighs about 9.8#, she should probably weight 12#

How old is your "kitty"?  And did the vet say she needed to gain weight?  9.8 oz seems like an okay weight to me especially for a female..  (Ritz has the opposite problem)

Here is a thread about how to get a cat to gain weight.  http://www.thecatsite.com/t/232739/cat-needs-to-gain-weight-what-to-feed

As mentioned, egg yolks are calorically dense and full of good vitamins and minerals.  I'd try to feed her three times a day, she may eat more that way.  And when reading labels, look for the fat content.  Duck is generally higher in calories than, say, chicken.

She is 14 years old, and yes the vet said she needs to gain weight.  You can feel her spine easily.

Gosh, as to the amount of food at each serving, that's really hard to say.  It really depends on the food, and how active DeeJay is, etc.  And whether or not she nibbles on anything else during the day.  There are so  many different things to take into consideration.  Are you adding in any egg yolks?  Giving her any freeze dried treat? 

My 6.5 lb cat sometimes only eats 2 oz a day , but she also gets freeze dried raw as treats all throughout the day, plus freeze dried cooked chicken treats at bedtime.  (as an aside, I SERVE 1.5 oz per meal to this cat, 3 - 4 meals per day, but am often disappointed at how little she eats ...just don't want anyone to think I am trying to starve her )

I will say, however, that whatever it says on the can is usually much more than is actually needed.  In DeeJay's case, what amount have you fed her in the past?  Older cats typically don't eat as much as they did when they were younger, simply because they aren't usually as active as they age. 

I have tried to give her about 2-3 oz twice a day, however am increasing it to 3 times a day now so she can gain some weight.  She does get some treats during the day but not a whole lot of them.  No dry food or anything like that she's strictly wet.

Well, again, it really depends on what foods you are feeding her.  BTW, have you tried feeding her kitten food?  Its usually higher in calories .

But, for example, Wellness Chicken has 220 calories in a 5.5oz can, compared to Fancy Feast Chicken Feast (Classic) has 91 calories in a 3 oz can.  On the other hand, Fancy Feast Salmon Gravy Lovers only has 65 calories per 3 oz can.

Here's a food chart you can refer to for calories (and other good info):  http://www.catinfo.org/docs/FoodChartPublic9-22-12.pdf

Thank you.  Yes going to figure out calories in what I am feeding her.  My hubby picked up some kitten food (Fancy Feast) for her to try, so far she likes it.  Right now I am just trying to get her to eat consistently.  She quit eating a few days ago, but we have her eating again now, I think she was getting bored with the same old food all the time.