The practice of using dogs and other animals as a part of therapy dates back to the late 18th century, when animals were introduced into mental institutions to help socialize patients with mental disorders.[201] Animal-assisted intervention research has shown that animal-assisted therapy with a dog can increase social behaviors, such as smiling and laughing, among people with Alzheimer's disease.[202] One study demonstrated that children with ADHD and conduct disorders who participated in an education program with dogs and other animals showed increased attendance, increased knowledge and skill objectives, and decreased antisocial and violent behavior compared with those who were not in an animal-assisted program.[203]
A 2005 paper states "recent research has failed to support earlier findings that pet ownership is associated with a reduced risk of cardiovascular disease, a reduced use of general practitioner services, or any psychological or physical benefits on health for community dwelling older people. Research has, however, pointed to significantly less absenteeism from school through sickness among children who live with pets."[191] In one study, new guardians reported a highly significant reduction in minor health problems during the first month following pet acquisition, and this effect was sustained in those with dogs through to the end of the study.[195]

The domestic dog is the first species, and the only large carnivore, known to have been domesticated. Especially over the past 200 years, dogs have undergone rapid phenotypic change and were formed into today's modern dog breeds due to artificial selection by humans. These breeds can vary in size and weight from a 0.46 kg (1.0 lb) teacup poodle to a 90 kg (200 lb) giant mastiff. Phenotypic variation can include height measured to the withers ranging from 15.2 centimetres (6.0 in) in the Chihuahua to 76 cm (30 in) in the Irish Wolfhound; color varies from white through grays (usually called "blue") to black, and browns from light (tan) to dark ("red" or "chocolate") in a wide variation of patterns; coats can be short or long, coarse-haired to wool-like, straight, curly, or smooth.[131] The skull, body, and limb proportions vary significantly between breeds, with dogs displaying more phenotypic diversity than can be found within the entire order of carnivores. Some breeds demonstrate outstanding skills in herding, retrieving, scent detection, and guarding, which demonstrates the functional and behavioral diversity of dogs. The first dogs were domesticated from shared ancestors of modern wolves, however the phenotypic changes that coincided with the dog–wolf genetic divergence are not known.[26]

A number of common human foods and household ingestibles are toxic to dogs, including chocolate solids (theobromine poisoning), onion and garlic (thiosulphate, sulfoxide or disulfide poisoning),[54] grapes and raisins, macadamia nuts, xylitol,[55] as well as various plants and other potentially ingested materials.[56][57] The nicotine in tobacco can also be dangerous. Dogs can be exposed to the substance by scavenging through garbage bins or ashtrays and eating cigars and cigarettes. Signs can be vomiting of large amounts (e.g., from eating cigar butts) or diarrhea. Some other signs are abdominal pain, loss of coordination, collapse, or death.[58] Dogs are susceptible to theobromine poisoning, typically from ingestion of chocolate. Theobromine is toxic to dogs because, although the dog's metabolism is capable of breaking down the chemical, the process is so slow that for some dogs even small amounts of chocolate can be fatal, especially dark chocolate.
A dog groomer is a service professional who provides dog grooming and basic hygiene care for your dog. Dog groomers are typically animal lovers who are competent and comfortable working with a wide range of dog breeds and temperaments. Dog groomers are knowledgeable about the care needs for different kinds of dog coats. A poodle will have different haircut needs than a shih tzu, for example, so it pays to have a trained pro provide the proper cut. Good dog groomers know how to safely clean your dog’s teeth, bathe your dog, and cut their nails without going too short. They understand how to trim the hair from around your dog’s face, express anal glands, and clean your dog’s ears. Many people who choose dog grooming as a profession also pursue other dog services such as attending veterinary school, running a doggy day care center, working as a professional dog walker, and more.
Dog intelligence is the ability of the dog to perceive information and retain it as knowledge for applying to solve problems. Dogs have been shown to learn by inference. A study with Rico showed that he knew the labels of over 200 different items. He inferred the names of novel items by exclusion learning and correctly retrieved those novel items immediately and also 4 weeks after the initial exposure. Dogs have advanced memory skills. A study documented the learning and memory capabilities of a border collie, "Chaser", who had learned the names and could associate by verbal command over 1,000 words[87]. Dogs are able to read and react appropriately to human body language such as gesturing and pointing, and to understand human voice commands, although a 2018 study on canine cognitive abilities found that dogs' capabilities are not more exceptional than those of other animals, such as horses, chimpanzees or cats.[88]
In 2013, an estimate of the global dog population was 987 million.[104] Although it is said that the "dog is man's best friend",[105] this refers largely to the ~20% of dogs that live in developed countries. In the developing world, dogs are more commonly feral or communally owned, with pet dogs uncommon.[50] Most of these dogs live their lives as scavengers and have never been owned by humans, with one study showing their most common response when approached by strangers is to run away (52%) or respond aggressively (11%).[106] Little is known about these dogs, or the dogs in developed countries that are feral, stray or are in shelters, because the great majority of modern research on dog cognition has focused on pet dogs living in human homes.[107]
The dogs' value to early human hunter-gatherers led to them quickly becoming ubiquitous across world cultures. Dogs perform many roles for people, such as hunting, herding, pulling loads, protection, assisting police and military, companionship, and, more recently, aiding handicapped individuals. This influence on human society has given them the nickname "man's best friend" in the Western world. In some cultures, however, dogs are also a source of meat.[133][134]

Show Stopping Style grooms dogs and cats in your home. I can kindly introduce puppies and kittens to brushing, clipping, blow drying, and having their nails done! They feel more secure staying home, and pet parents can be right there! I grind dog and puppy nails to avoid splintering and to make soft paws, and use gentle, all natural, species appropriate shampoo and ear cleaner. If you'd rather I take your pet to a nearby facility, only the cost of the facility will be extra. ... View Profile
Dogs have lived and worked with humans in many roles. In addition to dogs' role as companion animals, dogs have been bred for herding livestock (collies, sheepdogs),[154][17] hunting (hounds, pointers),[43] and rodent control (terriers).[17] Other types of working dogs include search and rescue dogs,[155] detection dogs trained to detect illicit drugs[156] or chemical weapons;[157] guard dogs; dogs who assist fishermen with the use of nets; and dogs that pull loads.[17] In 1957, the dog Laika became the first animal to be launched into Earth orbit, aboard the Soviets' Sputnik 2; she died during the flight.[158][159]
Dogs bear their litters roughly 58 to 68 days after fertilization,[17][71] with an average of 63 days, although the length of gestation can vary. An average litter consists of about six puppies,[72] though this number may vary widely based on the breed of dog. In general, toy dogs produce from one to four puppies in each litter, while much larger breeds may average as many as twelve.

Be patient. You may have to go over your dog's coat a few times before you have a smooth, even cut. Don't rush it! Give your dog as many breaks as necessary, and make sure to move your clippers slowly. Brushing up against the coat then going the spot with clippers again help to get a smooth cut. Do will have to be done many times before you are done.
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