Jane Burton / Sheltie and Dachshund dogs with their puppies.

Yves Lanceau / Domestic dog, Hungarian Sheepdog / Komondor, female and puppy, France

Yves Lanceau / Domestic dog, Old English Sheepdog / Bobtail, studio portrait

Ernie Janes / Border Collie, working dog looking through gate, Wales, UK

Ernie Janes / Border collie, head portrait, Norfolk, UK, May

Petra Wegner / Bobtail / Old English Sheepdog running towards camera, panting.

Petra Wegner / Group portrait of five dogs sitting, from left to rt: two mongrels, Rough Collie, Bobtail (Old English Sheepdog) and longhaired Chihuahua.

Petra Wegner / Group portrait of five dogs sitting, from left to rt: two mongrels, Rough Collie, Bobtail (Old English Sheepdog) and longhaired Chihuahua.

Petra Wegner / Bobtail / Old English Sheepdog, lying with a longhaired Chihuahua, tan and white coated.

Petra Wegner / Bobtail / Old English Sheepdog, sitting alongside a longhaired Chihuahua, tan and white coated.

Adriano Bacchella / Old English Sheepdog / Bobtail sitting in field.

Adriano Bacchella / Old English Sheepdogs / Bobtails in a line.

Adriano Bacchella / Old English Sheepdog / Bobtail puppies on haybale.

Nick Turner / Sheepdog with flock of sheep {Canis familiaris} Pembrokeshire, Wales, UK

Mark Raycroft / Shetland Sheepdog (Canis familiaris)

Mark Raycroft / Shetland Sheepdog (Canis familiaris) running

Mark Taylor / RF - Fawn and blue Belgian Shepherd Dog (Malinois) pup, age 12 weeks, walking. (This image may be licensed either as rights managed or royalty free.)

Mark Taylor / RF - Belgian Shepherd Dog (Tervueren) bitch, Colouring: Grey with dropped black mask. (This image may be licensed either as rights managed or royalty free.)

Mark Taylor / RF - Fawn and blue Belgian Shepherd Dog (Malinois) pup, age 12 weeks. (This image may be licensed either as rights managed or royalty free.)

Mark Taylor / RF - Fawn and blue Belgian Shepherd Dog (Malinois) pup, age 12 weeks. (This image may be licensed either as rights managed or royalty free.)

Mark Taylor / Black Belgian Shepherd Dog (Groenendael) bitch, walking.

Mark Taylor / Fawn and blue Belgian Shepherd Dog (Malinois) pup, age 12 weeks.

Mark Taylor / Fawn and blue Belgian Shepherd Dog (Malinois) pup, age 12 weeks, looking up.

Mark Taylor / Fawn and blue Belgian Shepherd Dog (Malinois) pup, age 12 weeks, sitting.

Mark Taylor / Fawn and blue Belgian Shepherd Dog (Malinois) pup, age 12 weeks, lying with head up.

Mark Taylor / Belgian Shepherd Dog (Tervueren) bitch, lying with chin on the floor.mask.

Neil Aldridge / A young Belgian Shepherd anti-poaching dog is trained to follow a scent trail at an Animals Saving Animals training facility in England before being deployed to Africa to protect endangered species.

Neil Aldridge / A young Belgian Shepherd anti-poaching dog training at an Animals Saving Animals training facility in England before being deployed to Africa to protect endangered species. August 2017.

Neil Aldridge / A Belgian Shepherd anti-poaching dog undergoes training at an Animals Saving Animals training facility in England before being deployed to Africa to protect endangered species. August 2017.

Neil Aldridge / A young Belgian Shepherd anti-poaching dog is trained to follow a scent trail at an Animals Saving Animals training facility in England before being deployed to Africa to protect endangered species. A...

Neil Aldridge / A young Belgian Shepherd anti-poaching dog is trained to follow a scent trail at an Animals Saving Animals training facility in England before being deployed to Africa to protect endangered species.

Neil Aldridge / Belgian Shepherd dog, young dog trained as rhino protection dog during poacher tracking training. Animals Saving Animals training facility, England. This dog will be deployed to Botswana of Rhino Cons...

Lynn M. Stone / Shetland sheepdog running in Common bluet (Houstonia caerulea) field. Haddam, Connecticut, USA. May.

Lynn M. Stone / Shetland sheepdog standing in Common bluet (Houstonia caerulea) field. Haddam, Connecticut, USA. May.

Ashley Cooper / Sheep dog wearing nail studded collar for protection from wolves. Picos de Europa National Park, Spain, June 2005

Ashley Cooper / Men with umbrellas in the rain at The Vale of Rydal Sheepdog Trials, in Ambleside, Lake District, UK. August 2010

Ashley Cooper / Men with umbrella in the rain at The Vale of Rydal Sheepdog Trials, in Ambleside, Lake District, UK. August 2010

Bruno D'Amicis / Maremma Sheepdog with sheep, Gran Sasso National Park, Abruzzo, Italy, June

Bruno D'Amicis / Maremma Sheepdog wearing traditional anti-wolf spiked collar, locally known as 'vreccale'. Gran Sasso National Park, Abruzzo, Italy, June.

Bruno D'Amicis / Maremma Sheepdog wearing traditional anti-wolf spiked collar, locally known as 'vreccale'. Gran Sasso National Park, Abruzzo, Italy, June.

Bruno D'Amicis / Maremma Sheepdog wearing traditional anti-wolf spiked collar, locally known as 'vreccale'. Gran Sasso National Park, Abruzzo, Italy, June.

Bruno D'Amicis / Maremma sheepdog resting, wearing traditional anti-wolf spiked collar, locally known as 'vreccale'. Gran Sasso National Park, Abruzzo, Italy, June.

Bruno D'Amicis / Maremma sheepdog resting, wearing traditional anti-wolf spiked collar, locally known as 'vreccale'. Gran Sasso National Park, Abruzzo, Italy, June.

Bruno D'Amicis / Maremma Sheepdog, close up with herd in the backgruond, Gran Sasso National Park, Abruzzo, Italy, June.

Bruno D'Amicis / Shepherd, with Maremma Sheepdog wearing traditional anti-wolf spiked collar, locally known as 'vreccale'. Gran Sasso National Park, Abruzzo, Italy, June.

Bruno D'Amicis / Maremma Sheepdog with sheep, Gran Sasso National Park, Abruzzo, Italy, June.

Bruno D'Amicis / Maremma Sheepdog wearing traditional anti-wolf spiked collar, locally known as 'vreccale'. Gran Sasso National Park, Abruzzo, Italy, June.

Bruno D'Amicis / Maremma Sheepdog wearing traditional anti-wolf spiked collar, locally known as "vreccale". Gran Sasso National Park, Abruzzo, Italy, June.