Age of dogs by human standards

Dogs have been serving people for hundreds of years. Being smart pets, they helped a person in a variety of ways. Any owner of these four-legged creatures is concerned about the life span of his dog, and for this reason, through observation and research, the ratio of human years to dog years was found.

To find out the age of a dog in comparison with human years, there are three ways to help, of which one is simple and quick.

How to find out the age of a dog?

Determining the age of a dog visually is quite difficult. It is easy to distinguish an adult dog from a newborn puppy, but only knowing all the signs of a particular year of life will help to understand the exact age of the animal. Below is a table that will help you accurately determine the age of a pet on such a basis as the quality of the teeth.

It should be remembered that you can approximately determine the age of the dog using the table: more accurate need to find out based on the date of birth. This happens because the quality of wool, teeth and physique also depend on the environment. Homeless mongrels quickly lose muscle due to a poor diet, and their coat can be exposed to diseases (lichen, skin diseases).

In a domestic environment, when the dog is given attention and care, the situation is opposite: the quality of his teeth and coat is above average, because loving owners monitor the health of the pet.

For this reason, the data in the table can be treated no more than critically.

Years ratio

In order for a person to easily understand how long dogs live on average, several methods have been created to calculate the “human” age of an animal. So, the owners of the four-legged understand how old the pet is, and can be guided by this figure. It is impossible to say exactly how old a dog is by human standards: three different methods of calculation create confusion. The differences between them are not too big, but they need to be taken into account. So, if, according to the simplified calculation, the dog is 35 years old, according to LeBeau’s theory, he is 45.

Before proceeding with the calculation, it is necessary to understand that it is impossible to find the perfect ratio of human life to that of a dog. Each dog has its own individual life, which includes the influence of the environment. This suggests that even after studying the average life length of a certain breed, it is impossible to understand with accuracy how old an animal is in human terms. For this reason, the age of the dog should not be combined with the human.

Simplified calculation

In the 20th century, the first, still primitive calculation of dog years with human years was born. The creators were veterinarians who needed to know approximately how the life expectancy of a person and a dog correlate. Veterinarians did not delve into this issue and study different dog breeds, but took an average lifespan of 10 years. The life expectancy of a person at that moment fluctuated greatly, and the arithmetic average of 70 years was taken into account.

Thus, a simplified calculation of life expectancy appeared, which boiled down to a simple conclusion: 1 dog year is equal to 7 human years. And although such a calculation cannot be called accurate due to the individual data of each breed of dogs not included in the calculation, the simplified method was most widely used among people because it was quickly remembered and easy to use. The correspondence table below allows you to find out how many “human” years a pet according to a simplified calculation method.

Being the most popular, the simplified calculation takes the last place in terms of accuracy. The method does not take into account any data (breed of the dog, the first years of life), which means that it cannot translate the age according to these signs.

Veterinarians simply created a simple way to explain to dog owners what period of life (youth, old age) a pet goes through.

LeBeau’s theory

A simple method of calculation did not satisfy the French veterinarian A. LeBeau, which is why he decided to study the biological characteristics of dogs. LeBeau found that the first year of a dog’s life cannot be counted as 7 years, because in 365 days the dog is fully formed as an adult, which cannot be said about a seven-year-old child. This is how a theory appeared in 1953, based on which the first year of a dog’s life was considered as 15 human years. The second year of a dog’s existence must be counted as 9. So a 2-year-old dog is equal to a 24-year-old human.

The logic of such a decision is due to the fact that the growth and development of four-legged pets stops after two years of life, and the dog is a mature creature.

In his research, the veterinarian took into account the following characteristics:

  • life expectancy;
  • age of puberty, readiness to breed – in most breeds, puberty occurs during the first year of life;
  • the age of maturity, the point at which the dog is fully formed as an adult, is basically the age of two years of the animal.

The table below takes into account the average weight category of dogs whose weight starts from 15 kg, but does not exceed 45.

Like the other two methods, LeBeau’s theory has been repeatedly criticized. However, the presence of variables such as the age of puberty and the moment of maturity highlight LeBeau’s theory as a more accurate way to determine the age of an animal in human terms.

Klaiber’s law

In 1930 in Switzerland, the scientist Max Kleiber describes a rule that relates body mass (weight) to individual metabolism (the rate at which food is completely digested). The law applies not only to dogs, but to all animals, it is suitable for determining the “human” years of a cat or parrot. Today, Kleiber’s law is also applied to plants.

In plain language the law establishes the relationship between the weight of the dog and the metabolism: The larger the animal, the longer it will live. That is, small breeds of dogs with a fast metabolism will live for some time less than a Russian wolfhound. The problem in the calculations is the dog’s average heart rate.

A wide spread of breeds suggests a different development of the cardiovascular system, which may cause inconsistencies in the table, which is compiled according to Kleiber’s law.

The table is designed for the average weight of dogs (10-25 kg).

Kleiber’s method has an average accuracy. It takes into account the weight and metabolism of a living being, so the number of years can vary individually for each individual. The advantage of the law is that it is universal and suitable for any living beings, which cannot be said about other methods of calculation.

Counting errors

There are many errors in the calculations. Each dog has an individual development, which is why it is almost impossible to accurately determine the “human” age. Some mistakes are the most common.

  • In a simplified calculation, the first year is counted as 7 years. The first 365 days in a dog’s life are underestimated – during this time, the development of the animal occurs at a doubling pace. Muscles are being formed, there is a preparation for puberty. For this reason, counting the first year of a dog’s life as 7 is wrong. To avoid error, the first 12 months should be taken as 14-15 human years.
  • The second year of a dog’s life is also considered an important period in a dog’s life. While the simplified calculation considers the second year as 7, it should be taken as 9-10 years. This often causes confusion in the calculations, but these conditions cannot be neglected.
  • Kleiber’s law does not specialize in dogs. For this reason, factors such as breed and physiological characteristics of the pet are not taken into account in the equation. Therefore, Kleiber’s law is not accurate when a quadruped breed implies a shorter life span than other breeds.

How to determine the age of a pet is described in the following video.