Black nose Rhodesian ridgeback
|Other names||African lion dog
African lion hound
|Domestic dog (Canis lupus familiaris)|
The Rhodesian ridgeback is a dog breed developed in Rhodesia now Zimbabwe. Its European forebears can be traced to the early pioneers of the Cape Colony of southern Africa, who crossed their dogs with the semi-domesticated, ridged hunting dogs of the Khoikhoi.
The Rhodesian Ridgeback has also previously been known as Van Rooyen's lion dog or the African lion hound or African lion dog—simba inja in Ndebele, shumba imbwa in Shona—because of its ability to keep a lion at bay while awaiting its master's arrival to make the kill.
The original breed standard was drafted by F. R. Barnes, in Bulawayo, Southern Rhodesia (now Zimbabwe), in 1922. Based on that of the Dalmatian, the standard was approved by the South African Kennel Union in 1927.
- 1 History
- 2 Description
- 3 Ridge genetics
- 4 Classification conundrum
- 5 Health
- 6 See also
- 7 References
- 8 External links
The Khoikhoi people who occupied the Cape Peninsula when the Dutch began trading with the area during the mid 17th century, had a hunting dog which was described as ugly, but noted for its ferocity when acting as a guard dog. This dog measured approximately 18 inches (46 cm) at the withers, with a lean but muscular frame. The ears have been described both as erect and hanging, but the most distinctive feature was the length of hair often growing in the reverse direction along its back. Within 53 years of Dutch settlement in Southern Africa and the origins of the wagon-trekking boers later known as Afrikaaners, who converted vast stretches of wild veldt into farmland, hunted for meat and defended their cattle herds, staff, and homesteads from lion, the Europeans were using these local dogs themselves.
By the 1860s, European settlers had also imported a variety of mainly European dog breeds to this area of Africa, including such dedicated hunting dogs as great Danes, bloodhounds, greyhounds, and terriers. These breeds were bred with the indigenous African dogs, including the dog of the Khoikhoi people, which resulted in the Boer hunting dogs, generically called names such as boerhund (Boer hound) in Dutch then its descendant language of Afrikaans, which are the chief forerunners to the modern Rhodesian ridgeback. Other breeds came from Arabian traders around the Horn of Africa and with Asian immigrants, particularly into the Cape Colony, and jackal coursing introduced from British India brought lurchers from England and Ireland and the borzoi or Russian wolfhound, and before the era of standardized modern breeds, several breeds may have more rarely have contributed to Rhodesian ridgeback genetics. Although there are few currently feral or domesticated dog breeds which feature ridgebacks, there is not much speculation that either the Phu Quoc ridgeback from Phu Quoc Island, Vietnam nor the Mah Thai Lang Aan or Thai ridgeback, the royal dog of Thailand has contributed to any significant degree, if any, to the KhoiKhoi ridgeback's primary trait ancestry for the dorsal hair pattern in the Rhodesian ridgeback.
Reverend Charles Helm (1844 - 1915), son of Reverend Daniel Helm of the London Missionary Society, was born in the Cape Colony, joined the London Missionary Society himself, and moved from the Zuurbraak (now Suurbraak) mission station just east of Swellendam (modern Western Cape Province, South Africa) to the Hope Fountain Mission in Matabeleland, Southern Rhodesia, travelling from October 1874 to December 1875, then bringing two ridged dog bitches from somewhere between Kimberley (modern Northern Cape Province, South Africa) and Swellendam with him to Hope Fountain in 1879 en route to becoming, as it would turn out, a political advisor to King Lobengula, house-host to hunter-explorer Frederick Courteney Selous, postmaster of Bulawayo and well-appreciated tooth-extractor. At Hope Fountain, now part of the city of Bulawayo, fellow South African transplant Cornelius van Rooyen (b. 1860, Uitenhage, modern Eastern Cape Province, South Africa), a big–game hunter, was married to Maria Vermaak of Bloemhof by Reverend Helm in 1879 the same year Helm brought his two rough-coated grey-black bitches to the Mission. Van Rooyen saw Helm's pair of bitches and decided to breed his own dogs with them to incorporate their guarding abilities. It is not known if these two first direct ancestors of Rhodesian ridgebacks had dorsal hair pattern ridges themselves, but they founded the Rhodesian ridgeback bloodline, so either carried the trait or it was added from other Boer dogs and hybrids with Khoikhoi ridgebacks which van Rooyen bred into his lines over many trials then generations.
After trying pointers and Airedales, crossing with collies gave van Rooyen the best lion hunters, as his son Cornelius Jr. tells us. Pointers, bulldogs (perhaps boerboels, which were actually mainly larger mastiffs) and greyhounds are generally credited in the European core of this mix, with larger terriers such as Irish terriers and perhaps great Danes. Modern Rhodesian ridgeback breeders speak of some of their ridgebacks being too 'mastiffy' though it is uncertain what extent, if any, of actual mastiff heredity may have entered, as from the boerboels and their descendants prevalent in these territories. After initially greyer, rough-coated litters originating from Helm's dogs, van Rooyen's subsequently crossed offspring turned to redder coats, incorporating the KhoiKhoi landrace dog's ridges already carried in Boer dogs within his genomes. They became the foundation stock of a kennel which developed dogs over the next 35 years with the ability to bay lions: that is, a pack of 4-6 Rhodesian ridgebacks holds lions at bay while the hunter makes the kill, though an individual Rhodesian ridgeback is no match for an adult lion in a fight. These dogs were used to hunt not only lions but also other game, including wild pigs and baboons, and they can kill a baboon independently of a human hunter's collaboration.
The original breed standard for the Rhodesian Lion Dog was drafted in 1922 by F. R. Barnes on founding the first Ridgeback Club at a Bulawayo Kennel Club show, then in Southern Rhodesia (now in Zimbabwe), and based on that of the Dalmatian. In 1927, Barnes' standard was approved by the South African Kennel Union with the name amended to Rhodesian ridgeback. Outside the subcontinent and internationally, the first Rhodesian ridgebacks in Britain were shown by Mrs. Edward Foljambe in 1928. In 1950, Mr. and Mrs. William H. O'Brien of Arizona brought six carefully selected Ridgebacks to the US from South Africa. He and his wife and Margaret Lowthian of California began the process of getting the breed accepted by the American Kennel Club. Similarly, in 1952, The Rhodesian Ridgeback Club of Great Britain was founded at Crufts to promote the breed around the United Kingdom to show judges, so a standard for the breed might be recognized. In 1954 the first Challenge Certificates were awarded to dogs shown as Rhodesian ridgebacks at United Kingdom competitions, toward their subsequent recognition by The Kennel Club of Great Britain, and in 1955 the American Kennel Club recognized the Rhodesian ridgeback breed as a member of the hound group.
The Rhodesian ridgeback's distinguishing feature is the ridge of hair running along its back in the opposite direction from the rest of its coat. It consists of a fan-like area formed by two whorls of hair (called "crowns") and tapers from immediately behind the shoulders down to the level of the hips. The ridge is usually about 2 inches (51 mm) in width at its widest point. It is believed to originate from the dog used by the original African dog population which had a similar ridge. The first depiction of a ridgeback is a wall painting describing the life of the Boers, housed in South Africa in the Voortrekker Monument.
Male ridgebacks usually stand 25–27 in (64–69 cm) at the withers and weigh about 85 lb (39 kg) (FCI standard); females are typically 24–26 inches (61–66 cm) tall and about 70 lb (32 kg) in weight. Ridgebacks are typically muscular and have a light wheaten to red wheaten coat, which should be short, dense, sleek and glossy in appearance, and neither woolly nor silky.
White is acceptable on the chest and toes. The presence of black guard hairs or ticking is not addressed in the AKC standard, although the elaboration of the AKC standard notes the amount of black or dark brown in the coat should not be excessive. The FCI standard states that excessive black hairs throughout the coat are highly undesirable. Ridgebacks sometimes have a dark mask. The dog's nose should be black or brown (liver) in keeping with the color of the dog. No other colored nose is permissible. The brown nose is a recessive gene. It is not as common as a black nose; some breeders believe the inclusion of brown noses in a breeding program is necessary for maintaining the vibrancy of the coat. The eyes should be round and should reflect the dog's color: dark eyes with a black nose, amber eyes with a brown (liver) nose. Ridgebacks have a strong, smooth tail, which is usually carried in a gentle curve backwards.
The original standard allowed for a variety of coat colors, including brindle and sable. The modern FCI standard calls for light wheaten to red wheaten.
Other dog breeds also have a reverse line of fur along the spine, including the Phu Quoc ridgeback dog and Thai ridgeback. The Thai ridgeback is a crossbreed of the Phu Quoc; historians have speculated the relationship between the Rhodesian ridgeback and the Phu Quoc with suggestions that historically one breed may have been imported to the other's location.
Rhodesian ridgebacks are loyal, intelligent, and somewhat aloof to strangers. This is not to be confused with aggression; a ridgeback of proper temperament will be more inclined to ignore, rather than challenge, a stranger. This breed requires positive, reward-based training, good socialization and consistency; it is often not the best choice for inexperienced dog owners. Ridgebacks are strong-willed, intelligent, and many seem to have a penchant for mischief, though loving. They are protective of their owners and families. If trained well, they can be excellent guard dogs. Like any dog, they can become aggressive when they are not socialized properly.
Despite their athletic, sometimes imposing, exterior, the ridgeback has a sensitive side. Francis R. Barnes, who wrote the first standard in 1922, acknowledged that "rough treatment ... should never be administered to these dogs, especially when they are young. They go to pieces with handling of that kind." The ridgeback accepts correction as long as it is fair and justified, and as long as it comes from someone it knows and trusts.
The genotype responsible for the ridge was recently found by a consortium of researchers at the Swedish University of Agricultural Sciences (Nicolette Salmon Hillbertz, Göran Andersson, et al.), Uppsala University (Leif Andersson, Mats Nilsson, et al.) and the Broad Institute (Kerstin Lindblad-Toh, et al.).
The only disqualification in the AKC standard for this breed is "ridgelessness". This term refers to the purebred offspring of heterozygous parental animals that do not inherit a copy of the ridge mutation from either parent and are, in effect, normal dogs without a ridged back. The most current research suggests that the ridge mutation is autosomal dominant with complete penetrance. However, while the few studies that have analyzed the issue do not agree on the incidence of ridgelessness within the breed, they all show a ridgeless rate significantly lower than 25%, which cannot be explained using the Punnett square model for single gene/two allele inheritance.
One possible reason for these studies to deviate from the expected 25% incidence of ridgelessness is inclusion of parents who were not heterozygous (possessing a copy of both the ridgeless and ridged allele) in the study. The inclusion of homozygotes (possessing two copies of the ridged alleles) would make the observed incidence be less than 25% when averaged across the population in the study. Heterozygotes are detected by mating the animal in question to either known heterozygotes or known homozygous recessives (other methods exist such as mating to offspring, but result in inbred offspring) and a heterozygote is detected when a ridgeless pup is born. Note that many matings are required to have a high probability of detecting a homozygous dominant (once a ridgeless pup is produced, the animal in question is assumed to be heterozygous without question), and more than one sire can produce the pups in one litter. The latter fact can cast doubt on the calling of male heterozygotes by this method and could possibly lead to the results shown in studies testing the mode of inheritance of ridgelessness. However, genetic test for copy number of ridge gene has been recently introduced in collaboration with Veterinary Research Institute, Brno, Czech Republic and can be ordered at http://www.genocan.eu/. Thus the breeders can have their animals tested and find out if the animal is heterozygote or dominant homozygote.
Traditionally, many ridgeback puppies were culled at birth for numerous reasons, including ridgelessness. Contemporary breeders are increasingly opting for surgical sterilization of these offspring to ensure they will not be bred but can live into maturity as non-showing, non-breeding pets. Some breed parent clubs and canine registries in Europe have even made the culling of ridgeless whelps a requirement. It was pointed out on the BBC One investigative documentary Pedigree Dogs Exposed that the Rhodesian Ridgeback Club of Great Britain's "code of ethics", which is ratified annually by the kennel club states that "Ridgeless puppies shall be culled", and that "mismarked" puppies will only ever be sold on condition that they are never shown, and are neutered. The Ridgeback Club defended itself pointing to the statement that follows, "if a breeder finds this morally impossible [to cull the puppy] the puppy shall be homed..." as indication that culling is not mandatory, but preferred. It was only after the publicity surrounding the promotion of culling that they reversed their code of ethics to say "no healthy puppy will be culled".
The historic and modern hunting uses of Rhodesian Ridgebacks have included everything from upland game birds to larger 'dangerous game'. While the hunting versatility of the breed has served it well in the field, it has caused much confusion and contention among ridgeback fanciers about what these dogs are, and are not, as hunting companions. Throughout its history, the Rhodesian ridgeback has been a breed of dog that has somewhat defied the strict interpretation of most conventional group classification paradigms.
In 1922 Bulawayo, Southern Rhodesia (Zimbabwe), Francis Barnes standardized the breed using the existing Dalmatian standard as a model - there was no mention of a preferred group placement. Although no parent club was 'officially' recognized at the time, in September 1924 the South African Kennel Union or SAKU (now the Kennel Union of South Africa or KUSA http://www.kusa.co.za/) began taking "lion dog" registrations. In February 1926, SAKU (KUSA) officially recognized the Rhodesian Parent Club. At the behest of Barnes, SAKU also made two changes at this time:
- The union's official name for the breed was changed from 'Rhodesian lion dog' to 'Rhodesian ridgeback'.
- The breed was placed in the union's 'gundog' group.
On this second point Barnes was emphatic, stating "I am breeding a gundog." The Rhodesian ridgeback remained classified as a gundog for over 20 years thence.
Although the Rhodesian ridgeback's bird hunting prowess has been well known throughout the breed's history (the original description from the South African parent club belabors this point in fact), it is important to note that the "gundog" classification made in 1920s Southern Rhodesia and South Africa was not specifically about bird hunting. To understand this it is necessary to understand the union's classification system at that time. The two likely categories Barnes could have chosen from within the SAKU classification system at that time were, "sporting" and "gundog". In the "sporting" group were the sighthounds and scenthounds. In the "gundog" group were the birddogs. This raises the question why Barnes rejected the group containing the sighthounds and scenthounds, and successfully lobbied in favor of the group containing the birddogs. Barnes' reasoning becomes clear with an understanding of the distinction between the two groups. The union's "sporting" dogs were those that would find game above ground, and were then expected to dispatch the game without assistance. The union's "gundogs" were those that find game above ground, and the human hunter was then expected to dispatch the game by means of a firearm. Within this context, the Rhodesian ridgeback—which was clearly expected to hold the lion at bay for the hunter, not to attempt to dispatch the lion unassisted by the gun—placement in the union’s gundog group becomes the logical choice within that system as it existed at that time.
Over time the culturally perceived meanings of the group labels had changed to those closer to their modern meanings, and the union eventually became a federated member of the FCI, and therefore adopted its group categorization system. By 1940, Barnes had resigned from the Rhodesian Parent Club and prompted by the lobbying of a newer generation of leadership within the Rhodesian Parent Club, in the 1950s, the breed's group classification was changed from "gundog" to "hound".
Today, there are at least five competing theories concerning proper group placement for the Rhodesian ridgeback.
Scenthound - This theory arises from the fact that the southern African landscape in general, and the Zimbabwean landscape specifically, is an extremely varied and diverse terrain, where a true sighthound would be severely handicapped in its finding ability in the game producing cover of the bushveldt, thornveldt, and kopjes. Proponents of the scenthound classification also observe that the ridgeback bears very little resemblance to the decidedly northern African desert breed sighthounds, in either form or function. And while proponents of this theory freely admit that ridgebacks are undoubtedly athletic 'running' dogs, they draw the distinction that ridgebacks do not pursue game by sheer speed, which is typical of the true sighthounds associated with the northern half of the continent.
Sighthound - This theory is based on the fact that some of the foundation stock used by Cornelius Van Rooyen during the creation of the breed was sighthound stock. Support for this theory has grown in areas (most notably in the United States) where ridgebacks have been allowed to compete with sighthounds in lure-coursing field trials. The theory's detractors contend that success in lure coursing trials does not in and of itself make a dog a true sighthound, and further bolster their contention by pointing out that ridgebacks are very poor performers when allowed to run in unofficial open field courses where they typically cannot keep up with the true sighthounds. Even so, no one can argue that ridgebacks have not been successful at lure coursing events. In fact ridgebacks have been very competitive in almost every lure coursing venue in which they have been allowed to compete. Proponents of this theory will often further defend it with a (debated) claim that while ridgebacks are versatile and use all their senses, their first and strongest inclination is to find game by sight—which itself is considered normal for dogs of any type, when the game is actually in sight.
Cur-dog - This theory is based on the United Kennel Club's (the leading 'working dog' registry in the U.S. in terms of numbers of dogs registered) classification system which, within the scenthounds, includes a sub-group known as "cur dogs". Contrary to the traditional/historical meaning of the term "cur", these dogs are neither mongrels, nor dogs of dubious breeding or value. Quite the contrary, the UKC cur-dogs are pure-bred, versatile hunting and livestock dogs. These pure breeds were typically developed by pioneering people who needed a dog that was highly protective of the family and farm, as well as a capable stock driver. Most importantly the dog was required to pursue various species of game both small and large game alike, in a manner inconsistent with the rest of the hounds (sight or scent). The cur-dog does so using all of its senses - hearing, sight, and scent as the situation demands. This classification theory is consistent with old breed descriptions, which are somewhat contrary to the more classical sighthound/scenthound types, like the one offered in an advertisement run by the Rhodesian Parent Club in a show catalogue in 1926, "... Rhodesian ridgeback (lion dogs) are unsurpassed for hunting and veld work. Ever faithful and loyal to their owners, highly intelligent and reliable guards."
Wagon dog/wagon hound - This theory was forwarded at the 2008 Rhodesian Ridgeback World Congress, and contends that an honest evaluation of the breed's functional history indicates that during its formative development and early use as a breed, the ridgeback was much more a "hunter's/farmer's ox-wagon dog" than it was a "lion dog". This theory aligns itself with the current FCI classification of the breed, group 6.3 (a special type of scenthound). However, the important distinction in this theory is not that the FCI classification of "scenthound" is accurate, but rather, that placing the Dalmatian and the Rhodesian ridgeback (the only breeds currently in FCI group 6.3), breeds that historically have served as versatile hunting/wagon dogs, should indeed be classified as two examples of the same type of dog, but further asserts that such dogs’ classification makes more sense as a discrete group. This classification theory is generally supported by historical accounts that mirror the one offered by Phyllis Archdale who went to Southern Africa in 1919 and bred ridgebacks there in the 1920s, "Old timers told me that in early days most Dutch transport riders had a Ridgehound as guard to their wagons. They were used to bail up lion and wild pig. Mine did both..."
Ridged primitive - There is also a group of ridgeback fanciers who believe Rhodesian ridgebacks should be thought of in terms of the FCI's group 5.8. FCI group 5 includes the spitz and related primitives. FCI group 5.8 specifically is "primitive type hunting dogs with a ridge on the back". The theory's detractors note that the Rhodesian ridgeback was not only developed in the late 19th century and standardized in the early 20th century, but developed specifically to "hunt to the gun" and as such is in fact a very modern creation, and anything but "primitive". But supporters of the theory contend that enough of the foundational stock is ancient, including the greyhound and the Khoikhoi dog (from which the ridged back derives), that even though it was developed relatively recently and for use with modern firearms, the breed can still be considered to be of a "primitive type".
Current registry classifications
Presently, the breed is categorized as a "hound" by every major registry throughout the world. For example, the British Kennel Club and the Canadian Kennel club both categorize the Rhodesian ridgeback as a hound, without any further specification. Both of the major registries in the United States, the AKC and the UKC, currently further distinguish the breed as a sighthound. The FCI, the largest international canine governing body, which looks to the parent club in the country of origin (the parent club in Zimbabwe) for the breed standard and group classification, currently further distinguishes the Rhodesian ridgeback as a scenthound.
Health conditions known to affect this breed are hip dysplasia and dermoid sinus. The ridgeback ranks number six in terms of most affected breeds for thyroid problems recorded by the Orthopedic Foundation for Animals. UK breed survey puts the average lifespan at 10.25 years.
Dermoid sinus is a congenital neural-tube defect that is known to affect this breed. The dermoid is often likened to a thin "spaghetti strand" beneath the skin. Puppies should always be screened at birth by the breeder and veterinarian, and the examination repeated as the puppies grow before they go to their new homes. This is done by palpation of the subcutaneous dorsal midline from the base of the skull to the insertion of the tail. Surgical removal is an option for affected neonates, puppies and adult dogs. All affected dogs, even those surgically corrected, should be spayed or neutered and never be bred, since surgical dermoid sinus removal can be extremely cost prohibitive, and because many unremoved dermoid sinuses will eventually abscess. Abscessed dermoid sinuses will be at best a recurrent, painful problem, and if the sinus communicates with the tissues around the spinal cord, cause meningitis and often death. However, it has been shown that supplementation of folic acid to the diet of the brood bitch before mating and during pregnancy reduces the incidence of dermoid sinus. One study on the Swedish population estimates that 8-10% are affected. Slightly less than 5% of ridgebacks were reported to be affected with the condition in a US breed club survey.
Degenerative myelopathy (DM) is a neurological disease of the spinal cord causing progressive paraparesis, most commonly in the German shepherd dog breed. It affects Rhodesian ridgebacks at a rate of only 0.75%. Signs of degenerative myelopathy are characterized at the beginning with foot dragging, and slipping of the rear limbs. The disease progresses to the point where the animal can no longer stand or walk on its own. Progression has been known to take as little as six months, or several years. There is a DNA test offered by the Orthopedic Foundation of Animals, to test for the gene. Animals who are at risk for the disease should not be bred to other animals at risk, as this creates future generations of this debilitating disease.
Hypothyroidism is a growing problem in the Rhodesian ridgeback, and this condition causes a multitude of symptoms, including weight gain and hair loss. Treatment for hypothyroidism in dogs consists of an inexpensive once-daily oral medication. Dr. Lorna Kennedy at the University of Manchester’s Centre for Integrated Genomic Medical Research in England has found the haplotype (group of genes), which, when present, double the chances of a Ridgeback becoming hypothyroid due to lymphocytic thyroiditis. This is important to the breed because lymphocytic thyroiditis is the overwhelming cause of hypothyroidism in ridgebacks.
RRCUS H&G - the Rhodesian Ridgeback Club of the United States maintains a web site devoted to the breed's health issues that also gathers ongoing research for their Health & Genetics Committee. This group recommends that breeders perform at least four health screenings: hips, elbows, thyroid and eyes, with cardiac and hearing tests optional.
CRRHS - it is also recommend that all ridgeback owners enter their dogs' information in the Comprehensive Rhodesian Ridgeback Health Survey.
- "Rhodesian Ridgeback" (PDF). FCI. Retrieved 10 October 2016.
- Fox (2003): p. 6
- "RRCUS - Rhodesian Ridgeback FAQ".
- "Learn all about the famous Phu Quoc Ridgeback Dog".
- "Thai Ridgeback".
- Category:Ridgeback dogs
- Wire, Pan-african News (14 March 2011). "Pan-African News Wire: The Relevance of the Anti-sanctions Campaign in Zimbabwe".
- "S2A3 Biographical Database of Southern African Science".
- "The men who created the Rhodesian Ridgeback dog we know today? (continued from Dec/Jan Bundu Times) – Rhodesian Association of WA (RAWA)".
- "History of Rhodesian Ridgeback".
- Fox (2003): p. 7
- Fox (2003): p. 10
- (Rhodesian ridgeback specific) Information kit for puppy buyers, Rhodesian Ridgeback Club of Victoria, Inc (AU), page 25, available online at oz.dogs.net.au/rrcv/uploads/documents/puppy_info13.doc as of June 21, 2015
- Fox (2003): p. 11
- "RRRCUS - The Rhodesian Ridgeback: Historical Information".
- Times (London), 11 October 1928, p. 11; 14 August 1933, p. 16
- The history-of-the-breed
- "Rhodesian Ridgeback Club of Great Britain".
- Club, American Kennel. "Rhodesian Ridgeback Dog Breed Information".
- "American Kennel Club - Rhodesian Ridgeback". Akc.org. Retrieved 2011-10-24.
- "About the Breed - Rhodesian Ridgebacks". 16 April 2016. Retrieved 2016-04-17.
- Denise Flaim (November 2002). "The Other End of the Leash Understanding Our Complex Hounds". AKC Gazette. New York, NY: American Kennel Club. 119 (11). ISSN 0033-4561. Retrieved 2009-07-31.
- Denise Flaim (November 2002). "The Other End of the Leash Understanding Our Complex Hounds". AKC Gazette. New York, NY: American Kennel Club. 119 (11). ISSN 0033-4561. Retrieved 2013-10-28.
- Salmon Hillbertz, NH; Isaksson, M; Karlsson, EK; Hellmén, E; Pielberg, GR; Savolainen, P; Wade, CM; von Euler, H; Gustafson, U; Hedhammar, A; Nilsson, M; Lindblad-Toh, K; Andersson, L; Andersson, G (Nov 2007). "Duplication of FGF3, FGF4, FGF19 and ORAOV1 causes hair ridge and predisposition to dermoid sinus in Ridgeback dogs". Nat Genet. 39 (11): 1318–20. doi:10.1038/ng.2007.4. PMID 17906623.
- "Internet Archive Wayback Machine". Web.archive.org. 2007-05-22. Archived from the original on May 22, 2007. Retrieved 2011-10-24.
- RESPONSE TO BBC PROGRAMME "PEDIGREE DOGS EXPOSED" The Rhodesian Ridgeback Club of Great Britain
- General Code of Ethics The Rhodesian Ridgeback Club of Great Britain
- "OFA Thyroid Statistics". Archived from the original on 26 May 2008. Retrieved 29 Oct 2014.
- "2004 Purebred Dog Health Survey" (PDF). Kennel Club/British Small Animal Veterinary Association. Retrieved 21 August 2010.
- "Health Issues RRCSA". Rrclubsa.com. Retrieved 2011-10-24.
- Hillbertz, N. H. C. S. (2005). "Inheritance of dermoid sinus in the Rhodesian ridgeback". Journal of Small Animal Practice. 46 (2): 71–74. doi:10.1111/j.1748-5827.2005.tb00295.x. PMID 15736812.
- Roethel, Cynthia. "Overview and Prevalence of Genetic Defects in the Rhodesian Ridgeback". RRCUS Health and Genetics Committee. Retrieved 25 February 2012.
- Fox (2003): p. 86
- "Rhodesian Ridgeback Health". Rhodesian Ridgeback Health. Retrieved 2011-10-24.
- "Rhodesian Ridgeback Comprehensive Health Survey Home Page". Lkhopkins.com. Retrieved 2011-10-24.
|Wikimedia Commons has media related to Rhodesian Ridgeback.|