The 2008 amendments also prohibited imports for resale of dogs unless they were at least six months of age, have all necessary vaccinations and are in good health. Furthermore, fines for violations of the Animal Welfare Act increased from $2500 to $10,000 per violation, per animal and per day. In 2013, "An Act to Amend the Animal Welfare Act to Modify the Definition of 'Exhibitor'," added an owner of a common, domesticated household pet who derives less than a substantial portion of income from a nonprimary source (as determined by the Secretary) for exhibiting an animal that exclusively resides at the residence of the pet owner, after stores, in section 2(h). Legislative and regulatory documents tracing the history of the Animal Welfare Act can be found on the Animal Welfare Act History Digital Collection. Licensing and registration The U.S Department of Agriculture (USDA) requires businesses that either buy or sell warmblooded animals, exhibit them to the public, transport them commercially, or use them in teaching or experiments, must be licensed or registered. Failure to become licensed or registered is a punishable violation of the Animal Welfare Act. Depending on the basis of the business, the Animal and Plant Health Inspection services (APHIS) determines whether the business should be licensed, registered, or both. Business owners are responsible for knowing about registration and licensing requirements. Businesses and activities covered Federal animal care standards mainly cover humane handling, housing, space, feeding, sanitation, shelter from extremes of weather, adequate veterinary care, transportation, and handling in transit. The same standards of animal care apply to all registered and licensed businesses. To make sure the regulation and standards are followed, APHIS field inspectors make periodic unannounced visits to all locations where animals are held. If any facility does not meet federal standards when they apply for a license or registration, they can receive up to three inspections within a period 90 days to correct any problems. The licenses are not issued until all problems are corrected. The facilities have to wait for a minimum of 6 months before reapplying for a license if they do not pass inspection within the 90-day period. Legal action results if the facility operates a regulated business without a license. Under the Animal Welfare Act, exhibitors and animal dealers must obtain a license, for which an annual fee is charged. APHIS does not issue a license until it inspects the facility