Is it true that one year of the dog’s life is equal to seven human?

It is generally accepted that to calculate the age of the pet, by human standards, it is necessary to use the coefficient of 7. We checked whether it is true.

The idea of ​​such a ratio is widely distributed among the people. On the Internet, you can read about it as on general websites ("Arguments and Facts", Biological Dictionary, Allcalc.ru), and on resources dedicated to directly dogs. The popularizer of science Mitio Kaku in his book writes about him "Physics of the future". Among famous writers, a similar proportion was mentioned Louis Aragon, Victoria Tokareva, Eduard Uspensky And many others.

We immediately note that a comparison of the ages of humans and animal is a very conditional thing. Under the “age of the dog in human years”, it is customary to understand the age at which a person is usually at the same stage of development as the dog in question. In addition, we are not talking about the individual characteristics of the development of a particular individual - the average indicators are taken into account.

The fact that the dog’s age is incorrect with human in linear coefficient, scientists spoke for a long time. In 1953, a veterinarian from France Albert Lebo proposed Theory, taking into account the accelerated development of dogs in the first 12 months of his life. According to his calculations, the dog, which reached puberty at the age of one year, corresponded to a 15-year-old teenager. During the second year of the dog’s life, its body will finish, therefore, the two-year-old PSU already corresponds to the physiological state of a 24-year-old young man. Each next year of the dog’s life is equated with four human. Thus, a three -year -old dog by human standards is 28 years old, a four -year -old - 32, eight -year -old - 48, etc.

And although the Lebo table is still widely used, one important factor is not taken into account - dependence on the breed, or rather, its average size.

Indeed, back in 1932, the Swiss biochemist Max Kleiber took off law metabolism in the body of animals. After a lot of experiments, he came to the conclusion that large animals live longer. Oddly enough, in the case of dogs, this law works exactly the opposite: Senbernars and Labradors, contrary to Swiss calculations, live 10-12 years, and Beijes - 14-16 years old. At the same time, at the same moment in time their “human” age is different, and the older they become, the more the difference in biological age grows. Nowadays, the following table based on the middle weight of the adult individual is more popular among veterinarians and dog handlers:

Finally, in November 2019, scientists of the University of California published studyin which they offered a completely new look at age. In their opinion, instead of calculating the calendar years, it is much more useful and more precisely to look at the change in the DNA of the dog. Experts believe that the biological age is necessary with the help of the so -called epigenetic hours - the totality of epigenetic tributaries of DNA, accumulating over time in the body of any mammal.

Many important physiological markers (such as, for example, the development of teeth) are manifested in different types at the same level of modification of the DNA molecule. Comparing the levels of this process, called methylation, in labidors-retrievers and people, the researchers deduced the formula with which the dog’s age to his equivalent in humans can be tied. The formula is as follows: the “human” age of the dog = 16 x ln (own age of the dog) + 31, where LN - Natural logarithm, that is, a logarithm on the basis e.

This is how this formula works in a graphic form (red curve):

As we see, the dogs at the beginning of their lives grow up very quickly (which was also confirmed by previous studies). Then the process of their aging slows down, and our pet conducts most of his life in a middle -aged state. However, unlike the previously existing opinion, the first dog year is approximately equal to seven (green curve) and not 12-15 (blue curve), but 31 human year. At the same time, scientists note that, despite all the differences between the breeds, the trajectories of their development are similar to each other.

Perhaps this study does not put an end to the question of interest to us. However, it can be unequivocally stated that, according to the modern point of view, the coefficient of 7 when calculating the age of the dog in human years is incorrect - the dependence here is definitely non -linear.

Not true

What do our verdicts mean?

Read on the topic:

1. The human age of your dog: a new scientific calculation formula
2. Quantitation Translation of Dog-to-Human Aging by Conserved Remodeling of Epigenetic Networks
3. Comparative Longevity of Pet Dogs and Humans: Implicates for Gerontology Research