Product name: Canis lupus familiaris Recombinants
Domestic dogs are now found all over the world. Their wild ancestors, the grey wolves, were found in the continental areas of the Northern Hemisphere, including North America and the Palearctic.
Other geographic terms: cosmopolitan
Domestic dogs are found in association with humans throughout the world and in a wide variety of habitats.
Domestic dogs come in an amazing variety of shapes and sizes. They have been selectively bred for millennia for various behaviors, sensory abilities, and physical attributes, including dogs bred to herd livestock (collies, herders, etc.), different types of game (Braco, hounds, etc.), catch rats (small terriers), guarding (mastiffs, chows), helping fishermen with nets (Newfoundlands, poodles), pulling loads (huskies, saint bernards), guarding carriages and horsemen (dalmatians) and as companion dogs. Some types were even bred simply as lap warmers (Pekingese). However, their basic morphology, no matter how modified, is that of their wild ancestors, the grey wolves.
Breeding in domestic dogs is usually handled by humans. Wild males tend to compete with each other for access to receptive females. Some populations of wild domestic dogs have reverted to ancestral habits in which a single pair of males and females (the alpha animals) dominate mating in a small family group or pack. Other pack members help care for the dominant pair’s offspring.
Domestic dogs have a gestation period of 9 weeks, after which anywhere from 1 to dozens of puppies can be born, depending on the breed and nutritional status of the mother. The average litter size is 3 to 9 pups. Male and female dogs typically reach puberty between 6 and 12 months of age; however, how long a dog actually breeds depends on many social factors, ranging from the size of the breed (larger dogs need more time before they are ready to breed) and the level of trust a dog must achieve before they are ready to reproduce.
Most breeds are seasonal monocyclics, showing signs of heat every 6 months or so. The reproductive cycle has four stages: anestrus, proestrus, estrus, and diestrus. The anoestrus period lasts about 2 to 4 months. Proestrus is the time when a bloody discharge first appears in a female. This is the beginning of the “heat”, a period that usually lasts 9 days but can last up to 28 days. The end of this period is marked by the woman’s acceptance of a male partner.
Estrus is the period when the female is sexually receptive and reproduction can occur. Ovulation occurs about 24 hours after the acceptance of the male. The eggs survive and can be fertilized for about 4 days after ovulation; therefore, it is possible for a female to mate with more than one male. Diestro follows estrus in the non-pregnant cycle, characterized by a “pseudo-pregnancy” state, which is followed by the return of the uterus and ovaries to the anestrus, resting state.
The longevity of domestic dogs depends on the care they receive, their breed and body size. In general, larger breeds have shorter lives. Well cared for animals can live 12 years or more.
Communication and Perception
Domestic dogs use a complex set of modes of communication to navigate their social environment. Chemical signals, such as pheromones, communicate information about reproductive status, social status, and mood. Body language is used a lot and various vocalizations are also used. Social bonding and communication also occur through touch.
Puppies have different eating habits than older dogs. A puppy needs twice the protein and 50% more calories per pound of body weight per day to meet her growth requirements. A quick change in a puppy’s diet can cause gastrointestinal upset. Puppies should be fed 4 times a day up to 3 months of age, 3 times a day up to 6 months, and 2 times a day for the rest of their lives. Senior dog eating habits are different in a couple of ways. The average-sized dog requires about 30 calories per pound of body weight per day. Interestingly, larger breeds need only 20 calories per pound of body weight, while smaller breeds need around 40 calories per pound of body weight.
A dog’s diet should consist of balanced portions of protein, carbohydrates, fats, and of course, water. A dog can go days without eating and lose 30% to 40% of its body weight without dying, but a 10% to 15% water loss could be fatal. Meat-based diets are not recommended for dogs due to the lack of calcium and iron found in meat. Dietary supplements should be avoided. Human foods that can be fatal to dogs include mouldy cheese, onions, and chocolate. Wild domestic dogs will eat a variety of foods, including animals and fruit.
Due to their association with humans, wild predators do not attack domestic dogs. However, wild domestic dogs can fall prey to any large predator. They are often killed by other canids, such as wolves and jackals.
Feral domestic dogs impact ecosystems primarily through predation on native wildlife, often resulting in severe population declines, especially of species endemic to the island. There are many species of parasites and pathogenic organisms that infect dogs. Some of which can also infect humans.
Economic Importance to Humans: Positive
If properly trained and treated well, dogs are loyal and protective animals. Domestic dogs have been bred for many purposes over the millennia, including as draft animals, guards, helpers for hunting, herding, fishing, and lap animals. More recently, the dogs are used as guide dogs for the blind, deaf and disabled, using their keen sense of smell to detect bombs or drugs, and as therapy animals.
Economic Importance to Humans: Negative
Domestic dogs carry and transmit human diseases, including viral, bacterial, and parasitic diseases. Dogs remain one of the main vectors of rabies transmission to humans in underdeveloped parts of the world. Additionally, domestic dogs are responsible for attacks on adults and children, sometimes resulting in death.