Anti-vivisection groups have reported on abuse of animals inside testing facilities. In 1997 footage secretly filmed by a freelance journalist inside Huntingdon Life Sciences in the UK showed staff punching and screaming at beagles.[79] Consort Kennels, a UK-based breeder of beagles for testing, closed down in 1997 after pressure from animal rights groups.[80]
Chihuahuas can be easily frightened or provoked to attack, so are generally unsuitable for homes with small children.[25] The breed tends to be fiercely loyal to one particular person and in some cases may become overprotective of the person, especially around other people or animals,[25] and tend to have a "clannish" nature, often preferring the companionship of other Chihuahuas or Chihuahua mixes over other dogs.[26] These traits generally make them unsuitable for households with children who are not patient and calm.[19]
With a compact size, easy-care coat and happy nature, the Beagle has long had a place as one of the most popular breeds for families. Beagles are also used as scent detection dogs at U.S. airports, where their friendliness allows them to search for weapons, drugs, and illegal food items without making passengers nervous the way a larger “police dog” might. The breed was developed in England to hunt rabbits, and Beagles are still happiest when following their noses. For that reason, they belong to a category of dogs known as scenthounds.

The merle coat pattern, which appears mottled, is not traditionally considered part of the breed standard. In May 2007, The Kennel Club decided not to register puppies with this coloration due to the health risks associated with the responsible gene, and in December of that year, formally amended its breed standard to disqualify merle dogs.[20] The Fédération Cynologique Internationale, which represents the major kennel clubs of 84 countries, also disqualified merle.[16] Other countries' kennel clubs, including Canada, Australia, New Zealand, and Germany, have also disqualified merle. However, in May 2008, the Chihuahua Club of America voted that merles would not be disqualified in the United States, and would be fully registrable and able to compete in AKC events. Opponents of merle recognition suspect the coloration came about by modern crossbreeding with other dogs and not by natural genetic drift.[21][citation needed]
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