Canis lupus familiaris (P#1)

Dog, Scientific name Canis lupus familiaris; It is a domestic carnivorous mammal of the canid family, which is a subspecies of the wolf (Canis lupus). Their average lifespan is around 15 years.

Ancestors and history

The dog is a domestic subspecies of the wolf according to the comparison of the genetic maps of both species. The oldest fossil evidence of a domesticated dog was found in 2008 in the Goyet Cave in Belgium, corresponding to about 31,700 years and apparently associated with the Aurignacian culture. Until then the oldest evidence had been found in Russia, dating back 14,000 years.

Embryo of a dog

Dogs are highly valued for their help in hunting. The dogs buried in the Mesolithic cemetery of Svaerdborg in Denmark show that, in ancient Europe, they were already valuable companions.

Dogs have always accompanied Man in his process to civilization; Their presence is proven in all cultures of the world, thus, in Peru, in the pre-Inca stage, the Mochicas used them as a hunting aid and also as pets at home. At the burial of the Lord of Sipán, remains of a dog that was used in hunting were found inside the tomb; the skull had perfectly developed molars. The skull and teeth of the domestic dog have decreased in size compared to those of the wolf as it no longer needs to kill large prey.

Likewise, by going from a meat diet to one made up of waste from human diet, they developed smaller brains that require fewer calories and less protein for their growth and sustenance. The perception of dogs by humans has varied and varies according to culture. In several American ethnic groups prior to 1492, as is still the case in areas of Far East Asia, dogs were used directly as food; In areas of the Middle East the dog has been associated by its appearance with jackals (in fact, it was scientifically believed until the development of genetics at the end of the 20th century that common dogs around the world were descendants of jackals) and being Jackals are mainly scavengers, dogs have also been considered impure in that area. Perhaps the only species of dog that is not descended from the wolf is the Fuegian dog that descends from the Culpeo.

Domestication Review

In the 21st century, researchers had reached an almost absolute consensus that it is very possible that the domestication of the dog began more with its spontaneous adaptation when approaching to live alongside man, than with human intention. This is because living alongside man has always been advantageous to the canid. A dog living in a human community, even in ancient times, could feed with less effort than a wild one, could live in better conditions and enjoy human affection and care. Man managed to domesticate specimens of wolves, or, more likely, he proved incapable of preventing wolves from entering their villages and having their pups there. The dog was useful as an aid in hunting and to defend the group and its home. Little by little, man adapted them to his needs, creating different races for different tasks and environmental and geographical characteristics.

The man quickly realized the dog's fine senses of smell and hearing; Its sense of smell is more powerful than that of a human (its olfactory area is 20 times thicker, and in the case of the German Shepherd with a surface area 34 times larger and with 40 times more olfactory cells) and its ear is capable of perceiving sounds far below and above the range that humans hear. This advantage increases its usefulness for hunting and guarding tasks. The use of him as a shepherd and protector of flocks is much later, going hand in hand with the domestication and exploitation of other animals. An animal with social customs, which lives in perfectly hierarchical groups, it adapted to living with humans.

Characteristics

Vision: The dog's vision seems designed for hunting: It does not have great visual acuity of details, but it has excellent perception of movements. It has excellent night or twilight vision, due to the use of the tapetum lucidum (a reflective screen inside the eye). The dog's visual field is between 240 - 250 degrees, much larger than that of the human, which is approximately 180 degrees.

Dogs have a form of dichromatic vision called Deuteranopia which in humans is considered a form of Color Blindness that affects red and green. Dogs perceive shades of yellow and blue, but they perceive red as yellow and green as gray.

Health: The average longevity of a dog varies greatly depending on the breed, and ranges between 8 and 15 years. If it is in good health, it can live up to 20 years, or even more; The oldest known dog reached 29 years of age. Small breeds tend to live longer than large and giant breeds.

The health of the dog, as in humans, is related to its type of life (balanced diet, physical exercise, education), especially during the periods of greatest vulnerability: growth, pregnancy, breastfeeding, work and old age. A large dog gains weight in a year at the same percentage as a man in 18. The causes of diseases are multiple and very varied.

Although sometimes it is the veterinarian who recommends what type of vaccine should be applied, it is important that the owner is aware that in terms of viral applications, an attenuated or modified virus vaccine works better in the animal's body, since this type Biologicals give a gradual increase in antibodies, achieving very effective protection and without the adverse post-inoculation effects that may exist with the application of a vaccine or active virus; The effects with this type of vaccine can range from simple fever and vomiting to anaphylactic shock or death.

Their characteristics vary depending on the breed, the exercise they do or their physical condition, but in general they range between the following values:

• Body temperature 38.5 - 39.5 °C (puppies and dogs that have just exercised may be a few tenths higher).
• Respiratory rate 20 - 40 breaths / minute.
• Heart rate 70 - 180 beats / minute and up to 220 in puppies (in general it is higher in puppies and small dogs than in adults and large dogs)
• Average age 8 - 16 years (higher in small breeds than in large breeds)
• Duration of growth, Small breeds. Up to 10 months Medium breeds: Up to 12 months Large breeds: Up to 15 months.
• Period of old age, small breeds. From 8 years old Medium breeds: From 7 years old Large breeds: From 5 years old.
• Sexual maturity. Between 8 and 12 months (earlier in small breeds)
• Interval between heats in the dog 6 months with a variation of 1 to 15 days.
• Duration of gestation 58 to 62 days.
• Weaning. After 30 or 45 days.