Sighthounds, also called gazehounds, primarily hunt by sight and speed, rather than by scent and endurance as scent hounds do.
These dogs specialize in pursuing prey, keeping it in sight, and overpowering it by their great speed and agility. They must be able to detect motion quickly, so they have keen vision. Sighthounds must be able to capture fast, agile prey such as deer and hare, so they have a very flexible back and long legs for a long stride, a deep chest to support an unusually (compared to other dogs) large heart, very efficient lungs for both anaerobic and aerobic sprints, and a lean, wiry body to keep their weight at a minimum. Sighthounds have unique anatomical and physiological features likely due to intentional selection for hunting by speed and sight; laboratory studies have established reference intervals for haematology and serum biochemical profiles in sighthounds, some of which are shared by all sighthounds and some of which may be unique to one breed.
The typical sighthound type has a light, lean head, which is dolichocephalic in proportion. This shape can create the illusion that their heads are longer than usual. Wolves and other wild dogs are dolichocephalic or mesaticephalic, but some domesticated dogs have become brachycephalic (short-headed) due to artificial selection by humans over the course of 12,000 years. Dolichocephalic breeds have a wider field of vision but smaller overlap between the eyes and therefore possibly poorer depth perception in some of their field of view than brachycephalic breeds; most, if not all, dog breeds have less visual acuity than their antecedent the wolf.
There is no science-based evidence to confirm the popular belief that sighthounds have a higher visual acuity than other types of dogs. However, there is increasing evidence that dolichocephalic breeds, thanks to a higher number of retinal ganglion cells in their “visual streak”, retain more heightened sensitivity than other breeds to objects and rapid movement in the horizontal field of vision.
Sighthounds such as the saluki/sloughi type (both named after the Seleucid Empire) have existed for at least 5,000 years, with the earliest presumed sighthound remains appearing in the excavations of Sumer dated approximately 7000–6000 BC. The earliest description of a sighthound in European recorded history comes from Arrian's Cynegeticus, of the 2nd century AD. Although today most sighthounds are kept primarily as pets, they have been bred for thousands of years to detect movement, chase, capture, and kill prey primarily by speed. They thrive on physical activity. Some have mellow personalities, others are watchful or even hostile towards strangers, but the instinct to chase running animals remains strong.
Apart from coursing, open-field coursing, and hunting, various dog sports are practiced with purebred sighthounds, and sometimes with Lurchers and Longdogs. Such sports include racing, lure coursing, and other events.
List of sighthounds
- Borzoi (Russian Wolfhound)
- Chart Polski (Polish Greyhound)
- Galgo Español
- Hortaya Borzaya
- Irish Wolfhound
- Italian Greyhound
- Magyar agár (Hungarian Greyhound)
- Old Croatian Sighthound
- Saluki (Persian Greyhound)
- Scottish Deerhound
- Silken Windhound
Debate about breed inclusion
There has been considerable debate in many quarters about what breeds are considered to be sighthounds. This is partially due to the fact that most Anglophone kennel clubs such as The Kennel Club and American Kennel Club do not have a "Sighthound" group per se, instead including them in the larger "Hound" group. Nonetheless, the Old World (FCI) understanding of the sighthound is quite clear and well documented: sighthounds are gräoid- (greyhound-) shaped dogs, which owe their specific build to their recorded function of speed hunting.
While this debate may simply appear to be a matter of semantics, it is of deeper importance when classifying breeds based on a thorough understanding of their true history and function. The original, authentic, and documented use of a breed is paramount in deciding its category as a hound, sighthound, or working breed. It is also of practical concern where the sport of lure coursing is concerned, typically only open to breeds that may be considered sighthounds by their national breed club, and where, particularly in North America, breeds from the Hound Group are increasingly finding their way into the informal sighthound group because they are recognized as "lure coursing breeds" by ASFA and the American Kennel Club.
For instance, the Canadian Kennel Club(CKC), the American Kennel Club (AKC) and the American Sighthound Field Association (ASFA) consider the Basenji, originally a breed that tracks and drives game, to be eligible for the purpose of lure coursing even though the Fédération Cynologique Internationale (FCI) does not. The Basenji is far from alone in this. The Rhodesian Ridgeback, was actually classified as a gun dog by its founding parent club for several decades, only to be changed much later. Since that time the Ridgeback has been mired in a perpetual "classification conundrum", and is considered to be a scent hound by the FCI.
Other breeds that fall into varyingly gray areas include the Ibizan Hound, Pharaoh Hound, Cirneco dell'Etna – all originally warren rabbit hunting and retrieving scent hounds not recognized as true sighthounds in their countries of origin – as well as the Portuguese Podengo, Peruvian Inca Orchid, and the Thai Ridgeback. All of these breeds are recognized as eligible to compete in lure coursing trials by either the American Kennel Club and/or the American Sighthound Field Association, but may not be by the Fédération Cynologique Internationale.
Purebred "breed" status in question
Many hunting dog types capable of hunting by speed and sight are not recognized as sighthounds, either informally or formally by a major kennel club. These include the following which all work as sighthounds:
- American Staghound, a crossbreed
- Kangaroo Dog, a crossbreed
- Khalag Tazi
- Levriero Italiano
- Longdog, a crossbreed
- Lurcher, a crossbreed
- Mudhol Hound
- Old Croatian Sighthound
- Rampur Greyhound
Breeds considered to be controversial, not having by origin a sighthound function
A number of breeds, or types of dogs, which do not hunt solely by speed and sight, as well as a number of non-hunting breeds, are currently being recognized as sighthounds, either informally  or formally by kennel clubs, or lure and live coursing clubs. These include:
- Canary Islands Hound Podenco Canario
- Cirneco dell'Etna
- Ibizan Hound (Podenco Ibicenco)
- Pharaoh Hound (Kelb tal-fenek)
- Portuguese Podengo
- Rhodesian Ridgeback
- Peruvian Inca Orchid
- Thai Ridgeback
|Wikimedia Commons has media related to Sighthounds.|
- Zaldívar-López, S.; et al. (2011). "Clinical Pathology of Greyhounds and Other Sighthounds". Veterinary clinical pathology / American Society for Veterinary Clinical Pathology. PMC. doi:10.1111/j.1939-165X.2011.00360.x.
- Roberts, Taryn; McGreevy, Paul; Valenzuela, Michael (July 2010), "Human Induced Rotation and Reorganization of the Brain of Domestic Dogs", PLoS ONE, 5 (7): e11946, doi:10.1371/journal.pone.0011946, PMC , PMID 20668685
- Miller, Paul E.; Murphy, Christopher J. (December 15, 1995), "Vision in Dogs" (PDF), Journal of the American Veterinary Medical Association, 207 (12): 1623–1634, PMID 7493905, retrieved 2012-12-24
- McGreevy, Paul; Grassia, Tanya D.; Harman, Alison M. (December 2004), "A strong correlation exists between the distribution of retinal ganglion cells and nose length in the dog", Brain Behavior and Evolution, 63 (1): 13–22, doi:10.1159/000073756
- AKC - Saluki History
- Talk:Sighthound#Controversial (or non-sighthound) listing
- Bengtson, Bo. Making It Count. How many Sighthound breeds are there? A dozen? Twenty? Bo Bengtson counts about 40... Sighthound Review Vol. 4, Issue 3 Fall/Winter 2013
- "Dogs built for speed have a long, slim body, which does not interfere with freedom of leg movement ..." page 32: Dogs in Motion M. S. Fischer and K. E. Lilje 2nd edition 2014 VDH GmbH ISBN 978-3-9814339-0-6
- Bauer, M., & Lemo, N. The origin and evolution of Dalmatian and relation with other Croatian native breeds of dog, Revue de Médecine Véterinaire 2008. 159(12):618-623
- Bengtson,Bo. How Many Sighthound Breeds? - Would you believe more than 50? Sighthound Review Vol 5, Issue 4 Winter 2014-2015
- Almirall, Leon V. Canines and Coyotes. Caldwell, Id.: The Caxton Printers, Ltd., 1941.
- Anderson, John Kinlock. Hunting in the Ancient World. University of California Press 1985.
- Belkin, Dan. "The Functional Saluki: Lessons from the Coursing Field". Field Advisory News, November/December 1993.
- Bengtson, Bo. "What IS a Sighthound?" Sighthound Review, Charter Issue May–June 1984.
- Bengtson, Bo. "What is a Sighthound?" Sighthound Review. January 2011.
- Brown, Curtis. Dog Locomotion and Gait Analysis. Wheat Ridge, Colo.: Hoflin Publishing, 1986.
- Burnham, Pat Gail. "Rhodesian Ridgebacks, and the Question of What is a Sighthound?". Field Advisory News, March/April 1992.
- Copold, Steve. The Complete Book of Coursing: Hounds, Hares & Other Creatures, rev. & expanded 2nd ed. Wheat Ridge, Colo.: Hoflin Publishing, 1996.
- Copold, Steve. Hounds, Hares & Other Creatures: The Complete Book of Coursing (1st ed.). Arvada, Colo.: D. R. Hoflin, 1977 (1996).
- Couto Veterinary Consultants. "Are Sighthounds Really Dogs?"
- Cunliffe, Juliette. Popular Sight Hounds. London: Popular Dogs Publishing Co. Ltd., 1992. ISBN 0-09-175025-3.
- Dansey, William. Arrian On Coursing: the Cynegeticus. London: J. Bohn, 1831 
- Grant-Rennick, Richard (ed.). Coursing: The Pursuit of Game with Gazehounds. Saul, Gloucestershire: The Standfast Sporting Library, 1977. ISBN 0-9502148-9-2.
- Hancock, David. "Sighthounds Their Form, Their Function and Their Future", Ramsbury: The Crowood Press Ltd, 2012. ISBN 978-1-84797-392-4.
- Hawkins, Richard. "What Is A Sighthound". Dogs In Canada, April 2006.
- Hawkins, Richard. "Sighthound Identity". The Performance Sighthound Journal, July–September 2007.
- Hull, Denison B. Hounds and Hunting in Ancient Greece. Chicago: University of Chicago Press 1964.
- Miller, Constance O. Gazehounds: The Search For Truth. Wheat Ridge, Colo.: Hoflin Publishing, 1988.
- Parker, Heidi G. et al Genomic Analyses Reveal the Influence of Geographic Origin, Migration, and Hybridization on Modern Dog Breed Development Cell Reports (19)697–708, 2017. 
- Phillips, A.A., and M.M. Willcock, (eds.). Xenophon & Arrian On Hunting with Hounds. Oxford: Aris & Phillips, 1999. ISBN 0-85668-706-5.
- Recum, Andreas F. von, Hunting With Hounds in North America. Gretna: Pelican Publishing Co. 2002. ISBN 1-58980-043-5
- Russell, Joanna. All about Gazehounds. London: Pelham, 1976. ISBN 0-7207-0926-1.
- Salmon, M. H. ("Dutch"). Gazehounds & Coursing. St. Cloud, Minn.: North Star Press, 1977. ISBN 0-87839-024-3.
- Salmon, M. H. ("Dutch"). Gazehounds & Coursing: The History, Art, and Sport of Hunting with Sighthounds, Rev. and expanded 2nd ed. Silver City, N.M.: High-Lonesome Books, 1999. ISBN 0-944383-49-1.
- Uhrikova, I. et al Haematological and biochemical variations among eight Sighthound breeds. Australian Veterinary Journal, Vol 91 (11) 2013 Summary by Dr. Dominique de Caprona 
- Wimmer, Barbara. Genetic Differences between Western bred Sighthound (FCI group 10) and Primitive breeds (FCI group 5)  See summary by Dr. Dominique de Caprona