This report, published in September 2015 in issue 171 of MUNDO ESTRANHO, was awarded the Award of Excellence at the 37ththThe Best of News Design award, given by the Society for News Design (SND).
ILLUSTRATIONS: Alexandre Jubran
1) SKELETON
Breeds vary greatly in shape and size, but dogs all have the same general bone structure. The skeleton is divided into two parts: the appendicular and the axial. The first includes the front and hind legs and the hips, while the axial includes the head, spine, tail and thorax. The canine bone system allows the head to rotate 220º
2) HEART
Like the human heart, the canine heart has four chambers: two atria and two ventricles. Blood enters the right atrium and travels to the right ventricle, which pumps fluid to the lungs. From there, the blood returns to the left atrium and then to the left ventricle, where it is pumped to the rest of the body.
Curiosity:Most dogs can learn 165 words, including signs and gestures. The border collie can get up to 250
3) STOMACH
The volume that the organ holds (8 liters) is large in relation to the size of the animal. This is due to its carnivorous regime, as the meat takes longer to be digested and, in the mouth, chewing is poorly developed, which slows down the digestive work. ) gives more space to the stomach, which dilates, avoiding problems
HOW DO DOGS DRINK WATER?
1. The organ descends with force below the water level, causing the liquid to splash
two. The tongue is curved backwards as it descends, so the amount of water splashed out is greater.
3. When the dog pulls its tongue, the water rises with an acceleration up to five times greater than that of gravity.
4. The animal closes its mouth and grabs the water before it falls back down.
LACTATION
During lactation, which lasts about six months, the female produces a volume of milk up to three times her own weight. Sometimes, some bitches cannot produce an adequate amount of milk or the litter is too numerous. In this case, the veterinarian recommends replacing it with a specific milk for dogs.
GALLOP AND PAWS
Dogs have two types of gallop: one started with the hind legs, similar to that of horses, and another started with the front legs, similar to that of big cats. The paws are essential in the movement of the dog, but they differ between breeds: some do not have spurs and others have two.
TAIL
The tail is an extension of the spine, with vertebrae and nerve endings. In addition to balance, it helps express feelings. Docking the tail was a practice used to avoid injury to animals in fighting fights – currently, the act is prohibited in Brazil without medical justification, because it brings harm to the animal
REPRODUCTION
Females, like humans, are born with a certain number of eggs. They reach sexual maturity between 6 and 12 months of age, depending on the breed. Gestation lasts an average of two months and generates between two and ten cubs, depending on the size of the female. Breeding usually occurs twice a year and a bitch can have puppies from different fathers in the same litter. Dogs stick after sex (pictured below) because the base of the penis swells so much that it gets stuck at the entrance to the vagina. It’s natural – they come off within 1 hour
Curiosity: Just like humans, dogs are victims of diseases such as depression and Alzheimer’s, as well as aging problems such as blindness.
HEARING
Depending on the breed, a dog can hear frequencies between 10 Hz and 40 kHz. In comparison, a human can reach 16 Hz to 20 kHz – that is, dogs hear sounds that we cannot. They can also hear four times the distance we can. To top it off, they can detect the source of the sound in just six hundredths of a second.
VISION
Dogs can divide a second into up to 80 frames, while humans can only 30. They can also see from a peripheral vision angle of about 250º, wider than ours (180º), due to the position of the eyes, to the side from the head
SMELL
A dog has an average of 220 million olfactory cells. This means that their sense of smell is up to 100,000 times more acute than that of a human being, who has around 5 million.
TACT
The parts of the dog most sensitive to touch and movement are the vibrissae, the long hairs located on the muzzle, eyebrows, ears and chin. The rest of the fur has, at its base, nerve endings that form a network, responsible for understanding tactile and thermal stimuli.
TASTE
There are about 1,700 taste buds scattered along the tongue. They contain small receptors in charge of passing taste information to the brain. Animals can taste sweet, salty, sour and bitter and have preferred tastes
A THOUSAND AND ONE LICKS
Excluding the brain, the tongue is the organ that has the most responsibilities
– WOUND HEALER: The dog uses his tongue to clean himself and soothe irritated wounds
– STIMULANT: Female dogs use their tongue to comb their puppies and stimulate excretion by licking their urogenital area
– RADIATOR: Dogs pant to release heat and not overheat. Four pairs of salivary glands deliver saliva to the mouth. There are two types: a thick one (mucus) and a watery one (serous), which keep the animal’s mouth always moist.
– HANDSHAKE: Licking people is a way to show affection
READ THE OTHER PARTS OF THIS ARTICLE
– Dog tree of life
– What are the differences between the body of man and dog?