The Rough Collie is a breed of dog developed originally for herding in Scotland. It is also well known because of the works of author Albert Payson Terhune, and was popularized in later generations by the Lassie novel, movies, and television shows. There is also a smooth-coated variety;
Three coat colors are recognized for Rough Collies: sable and white, where the “sable” ranges from pale tan to a mahogany; tricolour, which is primarily black edged in tan; and blue merle, which is mottled gray. All have white coat areas, in the collar, parts of the leg, and sometimes the tail tip. Some may have white blazes on their faces. The downy undercoat is covered by a long, dense, coarse outer coat with a notable ruff around the neck, feathers about the legs, a petticoat on the abdomen, and a frill on the hindquarters.
The desired size and weight varies among breed standards; male collies can stand 22 to 24 inches at the shoulder; the Female averages 2 inches shorter. The male can weigh (45 – 100 lbs) and the female can weigh the same or more than a male. A Collies average weight is about 50-60lbs.
One of the characteristic features of the Rough Collie is its head. This is light in relation to the rest of the body, and resembles a blunted wedge tapering smoothly from ears to black nose. The muzzle is well rounded, and never square. There is considerable variation in the colour of the head, however. The eyes are medium sized and attentive. The ears are supposed to be bent, the bottom part vertical and the tips sloped forwards, although the dog can lay them back, or hold them vertical when alert. Collies not for the show ring, many times have ears which do not bend at all.
The double layered coat needs to be brushed frequently and thoroughly to keep it in a show condition, but it does not require extensive care. Rough collies should show no nervousness or aggressiveness, and are good with children and other animals. However, they must be well socialized to prevent shyness. They are mid to large sized dogs, are suited to live in small apartments because of their calm disposition; as they are not high strung as the poodle, labrador and other hunting breeds. The herding instinct is very much apparent in some dogs, but other dogs do not show this as much. Rough Collies are very loyal and protective to their owners. They are a good family dog. They are eager to learn and to please and respond best to a gentle hand. They relish human company and should be let outside as they need to run and exercise. By nature gentle and domesticated, they are fearless in danger and will rush to defend their owners. Due to several booms in the popularity of this breed, breeders more concerned with profit than breeding good dogs have produced Collies that are high-strung, neurotic or extremely shy. These problems are not typical of well-bred Collies, and can usually be avoided by acquiring a Collie either through an ethical breeder or a good rescue organization.
The origin and history of the Collie dog breed is not entirely known, but we do know that it included ancestors originating in Scotland and northern England. Before this time, however, the breed has an ancestry that spans thousands of years as the Collie’s ancestors had been used to herd sheep and cattle for many centuries in both the Highlands of Scotland and throughout early England. The word “collie” is thought to come from the word for “black” or “coal” in Old English. The Scottish Collie breed consists of both the Rough Collie and the Smooth Collie. A division between long-haired and short-haired variants also existed in the 19th century. However, it is apparent that at one point the Collie was much smaller than today’s dog, like the many other working collie breeds. The ancestor of the Collie was short, somewhere around 14 inches or so at the shoulders with a broader head, and black or black-and-white. The dogs that came to be the Collie had been used to herd and guard the flocks and herds of their caretakers.
Although the Scottish Collie and its ancestors had been used for several centuries as a working dog herding sheep and cattle, it was in England in the 19th century that the dog became popular as a pet and show dog rather than a working dog breed. Queen Victoria took an interest in Scottish Collies and the rest of the country soon followed suit. It was also at this time that the dog became larger through cross-breeding with breeds such as Borzois. At this point, Collie breeders began to standardize the breed and keep written pedigree records. Collies were shown in dog shows in England as early as 1860 and made its way to the United states by 1880. By about 1886, the Collie breed was fully standardized and remains roughly the same today.
A surge in popularity occurred around the world in the 1940s and 1950s with the release of the movie “Lassie Come Home” in 1943 and the subsequent television series that began in 1954 and ran for seventeen years.
Both Rough and Smooth varieties are available in three distinct colors:
Sable collies are generally the most recognizable, the choice of the Lassie television and movie producers. The sable color on these dogs can range from a light blonde color to a deep reddish-brown, with any hue in between possible.
Tricolor dogs are mostly black and white with tan markings.
Blue merle collies are best described as tricolor or black-and-white dogs whose black has been diluted to a mottled gray-blue color.
As modern-day “Lassies”, both Rough and Smooth Collies have become successful assistance, and therapy dogs. At least one guide dog school, the Southeastern Guide Dogs in Florida) currently trains Smooth Collies as guide dogs, and a number of Collies are currently partnered with disabled individuals
The Scottish Collie is typically a very healthy breed, and is known to inherit few health conditions that are both serious and prevalent. Some health conditions of note include Collie eye anomaly, PRA (progressive retinal atrophy), gastric torsion, dermatomyositis, grey collie syndrome (a type of neutropenia), collie nose (discoid lupus erythematosus), and demodicosis. Seizures, canine hip dysplasia, microphthalmia, and cyclic neutropenia are also occasionally seen. The Collie Health Foundation (http://www.colliehealth.org) in the United States, maintains a website and database on disorders affecting collies.
Some Collies (and other collie breeds) have a particular allele of the multi-drug resistance gene, MDR1. This is also known as “the ivermectin-sensitive collie”, however the sensitivity is not limited to ivermectin, a common drug used to treat and prevent various ailments in dogs including heartworm disease. More than 20 drugs are expected to cause adverse reactions including milbemycin and loperamide. A study by the Veterinary Genetics Laboratory at UC Davis concluded that all dogs with this mutation are descendants of a single dog which most likely lived in Great Britain during the middle of the 19th century.
The mutation of the MDR1 gene is found in Collies and related breeds worldwide. Dogs with this mutation are predisposed to various sensitivities and some may suffer a potentially fatal neurotoxicosis.
Ivermectin is a popular choice in the prevention of heartworm disease in dogs, an extremely serious and potentially fatal condition. Despite the high prevalence of sensitivity in Collies to this medication, the low dosage provided is generally considered safe and preventative drugs such as Heartgard are advertised as approved for Collies, having a wide margin of safety when used as directed. A simple test, recently developed at and provided by Washington State University, can determine if a dog is a carrier of the mutation which causes sensitivity. 
Collies typically live an average of 12 to 14 years