USDA Requirements for Housing and Exercise
   

Housing Requirements
"Primary enclosure"
(Where the dog lives.)
Required to be as large as the length of his body from the nose to the base of tail + 6 in., squared

If a dog is nursing pups, she "must be provided with an additional amount of floor space, based on her breed and behavioral characteristics, and in accordance with generally accepted husbandry practices as determined by the attending veterinarian." This is open to interpretation. "Accepted husbandry practices" are agricultural practices for raising livestock on a farm. They are not appropriate for raising puppies to be family pets.

Exercise requirements
Dogs and pups in the following situations are exempt from exercise requirements:
(They don't have to be given/allowed exercise or out-of-cage time.)

» Puppies under 12 weeks old. Puppies can and often do live the first critical weeks of their lives in the same cage or kennel.

» Dogs housed alone and given at least twice the minimum housing space. At twice the space required, dogs still can't run, let alone walk more than a few steps. Breeding dogs may legally spend their entire lives in cages this size.

» Dogs housed in groups. If dogs live in the same cage or kennel and there is enough room so that each could have her own required floor space, it can be really crowded, and they are all exempt from exercise.

Link to full Animal Welfare Act
Housing requirements start on page 61.
Exercise requirements start on page 63.