Similar in appearance, rough collies and Shetland sheepdogs differ in size. Still, shelties are not miniature collies. Although both are herding dogs, they're two different breeds that vary in history, temperament and characteristics. Smooth collies have a shorter, flatter coat than their rough counterparts and do not resemble the sheltie. Rough and smooth collies share the same temperament and size.
Big and Little
An average male collie weighs between 60 to 75 pounds and stands 26 inches at the shoulder. The female collie weighs from 50 to 60 pounds and is 22 to 24 inches at the shoulder. The sheltie runs from 13 to 16 inches tall at shoulder height and weighs from 20 to 25 pounds. The collie muzzle is longer than that of a sheltie.
Both the rough collie and the sheltie carry a full, lush outer coat over a thick undercoat. The two breeds share similar colors, and can be sable, tri-color and blue merle. Collies can also be white with colored markings.
Shetland sheepdogs take their name from Shetland, the Scottish archipelago where the breed originated in the late 1800s. The small, agile sheepdogs were developed by shepherds there to withstand rough weather and rocky terrain. Sheltie ancestors are believed to be border collies, Scottish collies and spitz-type dogs -- perhaps Pomeranians.
Collies originated in Scotland during the 1800s to help farmers herd and guard livestock. The breed's exact origin is unknown, but the collie was refined in the mid-1800s when it gained popularity in England.
Alike but Different
Shelties and collies vary in temperament. Both breeds require regular exercise, but shelties need a job -- whether it's agility, herding, rally or conformation. A sheltie who's bored will find something to do, and it could be chewing your furniture. Shelties are smart, fun-loving, loyal and affectionate, but may be reserved with strangers. They require positive reinforcement and do not react well to aggressive training practices.
Collies are content to be quiet and more reserved than shelties. They are gentle, intelligent fast learners and will happily work when asked, but they are just as happy to nap. Collies can sometimes be stubborn. Both collies and shelties are good with children and wonderful family companions, although they may nip at the heels of their humans, attempting to herd them. This behavior is instinctive.
Health and Lifespan
A sheltie's lifespan averages 12 to 14 years; a collie's, eight to 12. Both breeds are generally healthy, but prone to some genetic issues. Both breeds can have eye problems, seizures and hip dysplasia. Collies can be prone to gastric torsion. Shelties may have hypothyroidism. These breeds can be sensitive to ivermectin in medications.