When a pet is bought, they need Care so they can stay alive, just like in real life. In the Nintendogs games, it generally means washing and brushing them regularly and feeding/walking them every day.
The first and the most simple thing to do is buy food for the adopted pet. Neglecting them without food or water for too long could reduce friendship with the dog and the loss of Trainer Points in the original game. Feeding them food regularly every day fills the pet up, and allows them to do various activities. Food comes in slightly different varieties and shapes, ranging from Jerky Treats to Milk.
In Nintendogs + Cats, feeding a pet some food will now affect the way how they perform physically. Feeding them too much Wet Food will make them overweight, and the pet run slower while giving them some Diet Food would make them underfed to the point of the pet getting tired easily. Make sure the pet is fed the right food, so they won't get too fat or thin when they perform in contests. Feeding them Premium Tinned Food makes them adjust to their ideal weight, no matter if they're fat or thin even though it can go for a high price.
Cleaning a Pet
When a pet gets dirty, the player will need to get some shampoo. In the first game, the player needs to either get Long or Short-Hair Shampoo type of shampoo to cater to the dog's coat otherwise the shampoo won't work that much. In Nintendogs + Cats, the shampoo only comes in one type and works on both long and short-haired dogs. Also, the player can buy Premium Shampoo which goes for a much higher price, but it makes the cleaniness of the pet's coat last longer.
In order for the pet to be washed, the player must use the stylus on the Touch Screen to scrub the pet with the shampoo. Once the pet is covered soapy bubbles, it must be washed all off with the shower so the pet would be clean. If the pet is dirty, the process must be done once more in order for it to have a very clean coat. When the pet is all clean, the coat itself will be all sparkly.
Pets can also be brushed, with the Wire Brush or Rubber Brush/Natural Bristle Brush, dependent on their coat length. It can be a cost-free alternative to the usual method of washing the pet in shampoo, even though it can take a little longer than it usually could. Brushing the pet is also essential for getting a higher score in the Obedience Trial, which increases the chances of the pet winning a better prize.