The Thai Ridgeback (Thai: ไทยหลังอาน, RTGS: Thai Lang-An) is an ancient breed of dog. The breed was formerly unknown outside of Thailand, but is gaining notice in the Western world. They are also known as a Mah Thai Lang Ahn. The Thai Ridgeback is one of only three breeds that has a ridge of hair that runs along its back in the opposite direction to the rest of the coat. The other two are the Rhodesian Ridgeback and the Phu Quoc Ridgeback.
The Thai Ridgeback is a muscular, medium-sized pariah-type dog with a wedge-shaped head, triangular-shaped prick ears, and a very short, smooth coat. It has a pronounced ridge on its back formed by hair growing in the opposite direction that extends from behind the withers to the hips. Puppies are occasionally born ridgeless. Thai Ridgebacks have a muscular and streamlined body, making them extremely agile. The tail is carried upward called a sickle or sword tail. Its forehead wrinkles with enormous expression. Like many eastern breeds, the Thai Ridgeback has retained a 'scissor jaw' where upper and lower teeth interlock when the jaw bones clamp down. The tongue can be black or have black marks. Eyes are almond-shaped and brown but may be amber in blue dogs. The ears are set low and point slightly outward. The ears stand up progressively during the puppy growth period, they are not cropped. The back is straight and level. The coat is short, hard, and straight. Due to the length and density of the coat shedding is minimal, occurring once or twice yearly. Because this breed does not have an undercoat the hair does not usually bother people allergic to other breeds of dogs. Coat must be solid colors of blue, black, red or fawn with a black mask being acceptable on reds. However, brindle and white are also found but are not acceptable colors. For international show and competition, shoulder height should be 22-24 inches (56–61 cm) in males and 20-22 inches (51–56 cm) in females. The weight averages 35–55 lbs in females and 40-60 lbs in males. Eight distinctive ridge patterns have been identified: needle, feather, arrow, lute, violin, bowling pin, leaf, and saddleback. All patterns are acceptable, but must be clearly defined and symmetrical. The broader the ridge, the more highly it is prized.
Thai ridgebacks are a hardy, overall healthy breed with few inherent health issues. The breed has reproduced in Thailand almost exclusively by natural selection until the very recent past. The domesticated population is small. Inbreeding depression has not been observed in the breed. Thai Ridgeback Dogs are prone to dermoid sinus. Modern lines of Thai Ridgeback, resulting from interpopulation crosses, may also be prone to hip dysplasia and other genetic disorders.
Thai Ridgebacks are an intelligent breed. The energy level is typically medium to high, with most of the day spent lounging and activity periods occurring in sporadic bursts. Well bred and properly socialized Thai Ridgebacks make loyal, loving family pets. They are naturally protective of their home and family and can be aggressive or shy when not properly socialized. They are best kept by consistent owners who have a thorough understanding of dog behavior. Because of prior geographic isolation and lack of human contact, the Thai Ridgeback remains independent minded and much of the original natural instinct and drives remain intact, particularly prey drive. Due to its nature, the Thai Ridgeback is not recommended for the novice dog handler. They have an excellent jumping ability and may seek to roam if not properly contained.
The ridgeback is under a control of two groups of epistatic genes. The first determines the existence of the ridge. The other determines the size of the ridge, from none to very large (down to the side). For the latter, the more the genes in the dog, the broader is the ridge. The ridge will appear only if there is at least one dominant allele in both groups.
Color Coat color is also under a control of two groups of epistatic genes. The first determines the color of the coat if it should be black, brindle, red or white. The series of dominance is black to brindle to red to white. The intensity of the coat color is under control of a set of modifying genes. The other group controls the dilution of the colors. Black can be dilute to gray/silver/blue, and red will turn fawn. The normal color is dominance over the diluted.
History The origin of the Thai Ridgeback is undocumented, but the breed was developed in eastern Thailand. The history of the breed is the subject of numerous hypotheses. The other existing purebreeds of ridgeback dog are the Rhodesian Ridgeback from Africa and the Phu Quoc Ridgeback from Vietnam, which is somewhat smaller than the Thai Ridgeback. Based on genetic-based hypothesis, both Thai Ridgeback Dog and Phu Quoc Dog are likely to be descended from Funan Ridgeback Dog which originated over 1,000 years ago in Funan Era of the region. The Hottentot Dog or Ari Dog (as called by the tribe), a known African ridgeback ancestor of the Rhodesian Ridgeback, is now extinct. Its link to the Funan Ridgeback Dog is very likely in a historian opinion. The possible genetic connection among the three remaining breeds is being investigated through DNA studies. The relationship between the Thai Ridgeback and the Rhodesian Ridgeback is uncertain, but possible through the Hottentot Dog or Ari Dog. There is minimal scientific proof that they are related.