A Florida, USA, veterinarian is offering 10 tips for pet owners on how much pet food should be fed to their dog or cat to maintain a healthy body weight.The first rule, according to Dr. Patty Khuly, is that regardless of which pet food brand, be sure to invest in a diet that is nutritionally balanced. For cats, Dr. Khuly says to add moisture to the feline food because a 2010 UK study found that at the end, cats fed moistened diets were more active and weighed less. She says pet owners must measure out their pet's food with a proper measuring tool to ensure the right portion. Pet owners should be consistent about the pet food brand and formula they feed or the way home-cooked petfood is prepared. Dr. Khuly also says pet owners should ask their vet to provide their pet's body condition score, which is an indicator of the need to lose weight if it is high. It may also be necessary to increase or decrease the petfood amounts over time, until reaching the perfect portion. Pet owners should not forget that treats contain calories too, which also affect a pet's weight. Also to ensure a healthy weight, pet owners should consider the amount of exercise their pet receives in determining the proper amount of food to feed. As pets age, their metabolism slows down, so pet owners should watch for these changes, Dr. Khuly says. Finally, she says that pet owners need to remember that all animals are different, and so, will have different nutritional needs.