The violet gland or supracaudal gland is a gland located on the upper surface of the tail of certain mammals, including European badgers and canids such as foxes, wolves, [1] and the domestic dog, [2] as well as the domestic cat. [3] Like many other mammalian secretion glands, the violet gland consists of modified sweat glands and sebaceous glands.
It is used for intra-species signalling, scent marking, and contributes to the strong odor of foxes in particular. Although it secretes a mixture of volatile terpenes similar to those produced by violets (hence the name), the chemicals are produced in much greater quantity than in flowers, and the resulting strong smell can be quite unpleasant.
In dogs, the violet or supracaudal gland is found approximately above the 9th caudal vertebra, but depending on breed it may be vestigial or entirely absent. The violet gland secretes protein and hydrophobic lipids, has wide excretory ducts, is connected with coarse hairs, devoid of cysts, and has no sexual dimorphism. In the dog and cat fancy it is often referred to as "stud tail", despite the fact that it occurs in both sexes, not just breeding males. However, for reasons still unknown the hair at a dog's violet gland tends to fall out when androgen levels are high over a prolonged time. In short-haired breeds the usually inconspicuous gland may thus appear as a noticeably sparsely haired patch, and it is this condition of the gland area that is most frequent in stud dogs.
In foxes, the violet gland is found on the upper surface of the tail, at roughly one-third of the tail's length from the body, and measures about 25 by 7.5 millimeters in red foxes. Due to its role in steroid hormone metabolism (and possibly production), foxes cannot be "de-scented" by removing this gland. For unknown reasons, the gland's secretions are fluorescent in ultraviolet light; this may result from the presence of carotenoids.
Canidae is a biological family of dog-like carnivorans, colloquially referred to as dogs, and constitutes a clade. A member of this family is also called a canid. The family includes three subfamilies: the Caninae, and the extinct Borophaginae and Hesperocyoninae. The Caninae are known as canines, and include domestic dogs, wolves, coyotes, foxes, jackals and other species.
The wolf, also known as the grey wolf or gray wolf, is a canine native to Eurasia and North America. More than thirty subspecies of Canis lupus have been recognized, including the dog and dingo, though grey wolves, as popularly understood, only comprise naturally-occurring wild subspecies. The wolf is the largest wild extant member of the family Canidae, and is further distinguished from other Canis species by its less pointed ears and muzzle, as well as a shorter torso and a longer tail. The wolf is nonetheless related closely enough to smaller Canis species, such as the coyote and the golden jackal, to produce fertile hybrids with them. The wolf's fur is usually mottled white, brown, grey, and black, although subspecies in the arctic region may be nearly all white.
A crossbreed is an organism with purebred parents of two different breeds, varieties, or populations. A domestic animal of unknown ancestry, where the breed status of only one parent or grandparent is known, may also be called a crossbreed though the term "mixed breed" is technically more accurate. Outcrossing is a type of crossbreeding used within a purebred breed to increase the genetic diversity within the breed, particularly when there is a need to avoid inbreeding.
The gray fox, or grey fox, is an omnivorous mammal of the family Canidae, widespread throughout North America and Central America. This species and its only congener, the diminutive island fox of the California Channel Islands, are the only living members of the genus Urocyon, which is considered to be genetically sister to all other living canids. Its species name cinereoargenteus means "ashen silver".
Dog communication is the transfer of information between dogs, as well as between dogs and humans. Behaviors associated with dog communication are categorized into visual and vocal. Visual communication includes mouth shape and head position, licking and sniffing, ear and tail positioning, eye gaze, facial expression, and body posture. Dog vocalizations, or auditory communication, can include barks, growls, howls, whines and whimpers, screams, pants and sighs. Dogs also communicate via gustatory communication, utilizing scent and pheromones.
The coat of the domestic dog refers to the hair that covers its body. Dogs demonstrate a wide range of coat colors, patterns, textures, and lengths.
The anal glands or anal sacs are small glands near the anus in many mammals. They are situated in between the external anal sphincter muscle and internal anal sphincter muscle. In non-human mammals, the secretions of the anal glands contain mostly volatile organic compounds with a strong odor, and they are thus functionally involved in communication. Depending upon the species, they may be involved in territory marking, individual identification, and sexual signalling, as well as defense. Their function in humans is unclear.
The short-eared dog, also known as the short-eared zorro or small-eared dog, is a unique and elusive canid species endemic to the Amazonian basin. This is the only species assigned to the genus Atelocynus.
The Pampas fox, also known as grey pampean fox, Pampas zorro, Azara's fox, or Azara's zorro, is a medium-sized zorro, or "false" fox, native to the South American Pampas. Azara in some of its alternative common names is a reference to Spanish naturalist Félix de Azara.
Scent gland are exocrine glands found in most mammals. They produce semi-viscous secretions which contain pheromones and other semiochemical compounds. These odor-messengers indicate information such as status, territorial marking, mood, and sexual behaviour. The odor may be subliminal—not consciously detectable. Though it is not their primary function, the salivary glands may also function as scent glands in some animals.
Canid hybrids are the result of interbreeding between the species of the subfamily Caninae.
Dog anatomy comprises the anatomical study of the visible parts of the body of a domestic dog. Details of structures vary tremendously from breed to breed, more than in any other animal species, wild or domesticated, as dogs are highly variable in height and weight. The smallest known adult dog was a Yorkshire Terrier that stood only 6.3 cm (2.5 in) at the shoulder, 9.5 cm (3.7 in) in length along the head and body, and weighed only 113 grams (4.0 oz). The heaviest dog was an English Mastiff named Zorba, which weighed 314 pounds (142 kg). The tallest known adult dog is a Great Dane that stands 106.7 cm (42.0 in) at the shoulder.
The dog is a domesticated descendant of the wolf. Also called the domestic dog, it was selectively bred from an extinct population of wolves during the Late Pleistocene by hunter-gatherers. The dog was the first species to be domesticated by humans, over 14,000 years ago and before the development of agriculture. Experts estimate that due to their long association with humans, dogs have gained the ability to thrive on a starch-rich diet that would be inadequate for other canids.
A perianal gland tumor is a type of tumor found near the anus in dogs that arises from specialized glandular tissue found in the perineum. It is also known as a hepatoid tumor because of the similarity in cell shape to hepatocytes. It is most commonly seen in intact dogs and is the third most common tumor type in intact male dogs. There are two types of perianal gland tumors, perianal gland adenomas, which are benign, and perianal gland adenocarcinomas, which are malignant. Both have receptors for testosterone. Perianal gland adenomas are three times more likely to be found in intact male dogs than females, and perianal gland adenocarcinomas are ten times more common in male dogs than females. The most commonly affected breeds for adenomas are the Siberian Husky, Cocker Spaniel, Pekingese, and Samoyed; for adenocarcinomas the most commonly affected breeds are the Siberian Husky, Bulldog, and Alaskan Malamute.
The corsac fox, also known simply as a corsac, is a medium-sized fox found in steppes, semi-deserts and deserts in Central Asia, ranging into Mongolia and northern China. Since 2004, it has been classified as least concern by IUCN, but populations fluctuate significantly, and numbers can drop tenfold within a single year. It is also known as the steppe fox. The word "corsac" is derived from the Russian name for the animal, "korsák" (корса́к), derived ultimately from Turkic "karsak".
The pale fox is a species of fox found in the band of African Sahel from Senegal in the west to Sudan in the east. It is one of the least studied of all canid species, in part due to its remote habitat and its sandy coat that blends in well with the desert-like terrain. The pale fox is distinguished by its light-colored fur and oversized ears, which enable it to excel in camouflage and survival in harsh environments.
Dogs, as with all mammals, have natural odors. Natural dog odor can be unpleasant to dog owners, especially when dogs are kept inside the home, as some people are not used to being exposed to the natural odor of a non-human species living in proximity to them. Dogs may also develop unnatural odors as a result of skin disease or other disorders or may become contaminated with odors from other sources in their environment.
Dog behavior is the internally coordinated responses of individuals or groups of domestic dogs to internal and external stimuli. It has been shaped by millennia of contact with humans and their lifestyles. As a result of this physical and social evolution, dogs have acquired the ability to understand and communicate with humans. Behavioral scientists have uncovered a wide range of social-cognitive abilities in domestic dogs.
The Hare Indian dog is an extinct domesticated canine; possibly a breed of domestic dog, coydog, or domesticated coyote; formerly found and originally bred in northern Canada by the Hare Indians for coursing. It had the speed and some characteristics of the coyote, and the domesticated temperament and other characteristics of a domestic dog. It gradually lost its usefulness as aboriginal hunting methods declined, and became extinct or lost its separate identity through interbreeding with dogs in the 19th century, though some claim the breed still exists in modified form.
Wolves communicate using vocalizations, body postures, scent, touch, and taste. The lunar phases have no effect on wolf vocalisation. Despite popular belief, wolves do not howl at the Moon. Gray wolves howl to assemble the pack, usually before and after hunts, to pass on an alarm particularly at a den site, to locate each other during a storm or while crossing unfamiliar territory, and to communicate across great distances. Other vocalisations include growls, barks and whines. Wolves do not bark as loudly or continuously as dogs do but they bark a few times and then retreat from a perceived danger. Aggressive or self-assertive wolves are characterized by their slow and deliberate movements, high body posture and raised hackles, while submissive ones carry their bodies low, sleeken their fur, and lower their ears and tail. Raised leg urination is considered to be one of the most important forms of scent communication in the wolf, making up 60–80% of all scent marks observed.