Pitbull

The term Pit Bull is used in reference to multiple breeds of dogs. Namely, the American Pit Bull Terrier, American Staffordshire Terrier and Staffordshire Bull Terrier, as well as any crosses between the three. However, in a few parts of the world the American Bulldog is also classified as 'Pit Bull' type dog, despite the fact that they have major genetic differences. In the 90's, the American Bully was created from the American Staffordshire Terrier and the American Pit Bull Terrier.

Jack Russel Terrier

The Jack Russell terrier is a small terrier that has its origins in fox hunting. It is principally white-bodied smooth, rough or broken-coated which is commonly confused with the Parson Russell terrier (the American Kennel Club (AKC) and affiliate variant) and the Russell terrier (a shorter legged, stockier variety, whose name within the Fédération Cynologique Internationale is "Jack Russell terrier"), with the term "Jack Russell" commonly misapplied to other small white terriers. The Jack Russell is a broad type, with a size range of 10–15 inches (25–38 cm), the Parson Russell is limited only to a middle range with a standard size of 12–14 inches (30–36 cm), while the Russell terrier is smaller at 8–12 inches (20–30 cm), however each breed has different physical proportions according to the standards of their breed clubs.
Originating in the early 19th century from dogs bred and used by Reverend John Russell, it has similar origins to the modern Fox terrier. The Jack Russell is an energetic breed which relies on a high level of exercise and stimulation, and is relatively free from serious health complaints. It has gone through several changes over the years, through different use and breed standards set by kennel clubs. Recognition for the breed by kennel clubs has been opposed by the breed's parent societies – which resulted in the breeding and recognition of the Parson Russell terrier. Jack Russells have appeared many times in film, television and print with several historical dogs of note.

Rough Collie

The Rough Collie (also known as the 'Long-Haired Collie') is a long coated breed of medium to large size dog that in its original form was a type of collie used and bred for herding in Scotland. Originating in the 1800s, it is now well known through the works of author Albert Payson Terhune, and through the Lassie novel, movies, and television shows. There is also a smooth-coated variety; some breed organisations, including both the American and the Canadian Kennel Clubs, consider the smooth-coat and rough-coat dogs to be variations of the same breed. Rough Collies generally come in shades of sable, merles, and tri-coloured. This breed is very similar to the smaller Shetland Sheepdog which is partly descended from the Rough Collie.The Rough Collie is more historical.

Chihuahua

Breed standards for this dog do not generally specify a height; only a weight and a description of their overall proportions. As a result, height varies more than within many other breeds. Generally, the height ranges between six and ten inches; however, some dogs grow as tall as 12 to 15 inches (30 to 38 cm). Both British and American breed standards state that a Chihuahua must not weigh more than six pounds for conformation. However, the British standard also states that a weight of two to four pounds is preferred and that if two dogs are equally good in type, the more diminutive one is preferred. The Fédération Cynologique Internationale (FCI) standard calls for dogs ideally between 1.5 and 3.0 kg (3.3 and 6.6 lbs.), although smaller ones are acceptable in the show ring.[8] Pet-quality Chihuahuas (that is, those bred or purchased as companions rather than show dogs) often range above these weights, even above ten pounds if they have large bone structures or are allowed to become overweight. This does not mean that they are not purebred Chihuahuas; they do not meet the requirements to enter a conformation show. Oversized Chihuahuas are seen in some of the best, and worst, bloodlines. Typically, the breed standard for both the long and short coat chihuahua will be identical except for the description of the coat.
Chihuahua breeders often use terms like Teacup, Pocket Size, Tiny Toy, Miniature or Standard to describe puppies. These terms are not recognized by the breed standards and are considered marketing gimmicks to inflate the value of puppies.[9] Chihuahuas are commonly referred to as either Apple or Deer heads,[10] the former having short noses and rounded heads similar to that of an apple, and the latter having longer noses and more elongated heads.

Bulldog

Bulldog is the name for a breed of dog commonly referred to as the English Bulldog. Other Bulldog breeds include the American Bulldog, Olde English Bulldogge, Australian Bulldog and the French Bulldog. The Bulldog is a muscular heavy dog with a wrinkled face and a distinctive pushed-in nose. The American Kennel Club (AKC), The Kennel Club (UK) and the United Kennel Club (UKC) oversee breeding standards.

Border Collie

The Border Collie is a herding dog breed developed in the Anglo-Scottish border region for herding livestock, especially sheep. It is the most widespread of the collie breeds.[citation needed]
Typically extremely energetic, acrobatic, and athletic, they frequently compete with great success in dog sports, in addition to their success in sheepdog trials, and are often cited as the most intelligent of all dogs.[1] In January 2011, a Border Collie was reported to have learned 1,022 words, and acts consequently to human citation of those words.[2][3]

Beagle

The Beagle is a breed of small to medium-sized dog. A member of the Hound Group, it is similar in appearance to the Foxhound, but smaller, with shorter legs and longer, softer ears. Beagles are scent hounds, developed primarily for tracking hare, rabbit, and othergame. They have a great sense of smell and tracking instinct that sees them employed as detection dogs for prohibited agricultural imports and foodstuffs in quarantine around the world. Beagles are intelligent, and are popular as pets because of their size, even temper, and lack of inherited health problems. These characteristics also make them the dog of choice for animal testing.
Although beagle-type dogs have existed for over 2,000 years, the modern breed was developed in Great Britain around the 1830s from several breeds, including the Talbot Hound, the North Country Beagle, the Southern Hound, and possibly the Harrier.
Beagles have been depicted in popular culture since Elizabethan times in literature and paintings, and more recently in film, television and comic books. Snoopy of the comic strip Peanuts has been promoted as "the world's most famous beagle.