a cup is 8 ounces so if she's getting 3/4 of a 16 OZ cup she's getting a cup and a half each feeding for a total of 3 per day. Somewhere on the bag of food it should tell you how many calories per cup the food has. If you find one lower in fat it will probably have fewer calories per cup (look at healthy weight formulas) and you may be able to give her more food with fewer calories. Also, you can give her some veggies to fill her belly. There are many who do that here. Frozen green beans seem to be well liked. She needs exercise so maybe short walks on a short leash will help.