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Cancer, not unique to humans, is common to almost all animals.
A few years ago, scientists dug up a 76-million-year-old dinosaur fossil from Canada and found traces of osteosarcoma. This is the oldest tumor ever found! Interestingly, dinosaurs and human osteosarcomas grow in basically the same location.
Different animals have different probabilities of getting tumors. Dogs and cats, as human favorite pets, suffer from more cancer. The most important reason is that the life expectancy of domestic pets far exceeds that of their wild counterparts: stray dogs and stray cats generally live for about 3 years, but under the love and care of their owners, it is not surprising that pet cats and dogs live for more than 10 years. When I was studying in the United States, I met a 23-year-old cat, which was older than I was at the time. Finally, it died of a tumor.
Recently, American scientists issued a paper that counted the data of more than 3,000 pet dogs with cancer, and found some phenomena that most people do not know.
First of all, the most common cancers in dogs are lymphoma and leukemia, followed by osteosarcoma.
Notably, all three types of cancer are more common in humans, adolescents, and children. Considering that pet cats and pet dogs are generally less than 10 years old when they get cancer, is there any scientific principle behind the similarity of this tumor type?
The distribution of tumor types in dogs, a total of 3452 individuals
Childhood tumors are not smaller adult tumors, regardless of type, genetic mutation, or immune escape mechanism. Compared with common tumors in the elderly, there are very few scientific studies on children's tumors.
Because of the similarity between cat and dog tumors and childhood and adolescent tumors, some scientists have used various dog tumors as models to study the pathogenesis of human childhood tumors and test new treatments, which is worth looking forward to.
If you develop drugs that can treat both pet dogs and children with tumors by studying dog tumors, it would be too cool.
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The second important finding is that although different breeds of dogs can develop cancer, the risk varies greatly!
We all know that dogs are a particularly diverse animal, with many varieties and huge differences. The difference between a Chihuahua and a Tibetan Mastiff is not a little bit.
I want to hold a Chihuahua and I want to run when I see a Tibetan mastiff.
In terms of cancer risk, different dogs also have obvious differences: some dogs get tumors earlier, and some get them much later.
Statistics have found that the most likely varieties to get tumors, the average age of cancer is only 5 years old, and the varieties that are not easy to get tumors, the average age of cancer is more than 10 years old, more than doubled!
Everyone must be interested, which dogs are more likely to get tumors, and which ones are luckier?
Don't sell it, just announce the list! No. 1 prone to cancer, Masteve dog!
Immediately behind the 2nd~4th are Saint Bernard, Great Dane, Bulldog and Irish Wolfhound. Their median age of cancer is 5~6 years old:
The first 5 breeds of dogs with cancer
At the other extreme, the most cancer-proof one seems to be the curly bichon! The median age of cancer is as high as 11.5 years.
Curly Bichon
The 2nd~4th places are the West Highland White Terrier, the American Stafford Summer Terrier, the Miniature Schnauzer and the Beagle.
The 5 last breeds of dogs to develop cancer
Seeing this list, dog lovers should have discovered at a glance: there is a clear difference between dogs that are prone to cancer and dogs that are not prone to cancer!
Do you see that?
Yes, these dog types are not the same!
Those who are prone to cancer are generally large and powerful, and those who are not prone to cancer are generally small and cute.
Five small strong anti-cancer, just one word: cute!
Five small strengths of cancer prevention: Just looking at the picture I want to take it home
Statistics have found that one of the indicators that is obviously related to the age of dog cancer is weight!
Simply put, the heavier the dog, the higher the overall risk and the younger the average cancer age.
Many people may not have a concept of the name of the Mastiff dog with the first risk of cancer, but you must be familiar with a subtype of this dog: "Tibetan Mastiff".
It also has a name: Tibetan Mastiff!
Last year, there was news in Taiwan: the Tibetan mastiff, which is prone to cancer, met the Bichon dog, the first in cancer prevention, what happened? Without suspense, Bichon was seriously injured by a Tibetan mastiff and died.
The owner of the Tibetan mastiff protested: It is clear that "Bichon" called the first one!
Image from the web
The other 4 breeds that are prone to cancer are also relatively large dogs. There are also many people who like them, but they are certainly not fancy "moe".
Body size is related to cancer risk, and this is similar to humans. I've written before that a person's height and cancer risk are directly related. Whether men or women, for every 10 cm more height, the risk of cancer increases by 8%~10%. (Further reading:
Tall people are more likely to get cancer? It's actually true!
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The world is fair, and there is a price for Yushu to be in the wind.
It should be emphasized that this is about probability, not prediction of cancer. In fact, many people, whether tall or dangerous, large dogs, will never get cancer for life. It's just that the relative risk is a little higher.
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Size is not the only factor that determines a dog's risk of cancer.
Innate genes are also involved. Even with the same weight, some varieties are at higher risk than others.
The more dangerous are the Bulldog, Boxer Dog, Vizla, and Boston Terrier, whose cancer age is more than 2 years younger than predicted by the weight model, indicating that such purebred dogs may be born with certain genes that are more likely to cause cancer.
Similarly, as with people, sex is related to cancer risk, and male dogs have a greater risk of cancer than female dogs. Considering that male dogs are no more likely to smoke and drink than female dogs, innate genes and hormones should be the main reason.
Speaking of hormones, research has also found that there is a way to significantly reduce the risk of cancer in dogs!
What is it?
Sterilization!
Whether male or female, the age of cancer in dogs that have undergone sterilization surgery has been significantly delayed, and the overall age has changed from more than 7 years old to about 9 years old.
It seems that life really makes choices all the time, and it is impossible to want both. Group reproduction, and individual health, are often not in line with interests.
It is true that eunuchs as a whole lived much longer than the emperor. Eunuchs who do not breed but may live a long life, emperors who breed desperately but may live a short life, what do you say?
If I were to say, don't go to extremes in anything. I choose to be a healthy ordinary person.
The overall list is revealed!
What is the number one fur child in your family?
Bibliography:
1. Age at cancer diagnosis by breed, weight, sex, and cancer type in a cohort of more than 3,000 dogs: Determining the optimal age to initiate cancer screening in canine patients. PLoS One. 2023 Feb 1;18(2):e0280795.
2. Breed-Predispositions to Cancer in Pedigree Dogs. Isrn Vet Sci. 2013; 2013: 1–23.