{"id":9183,"date":"2024-04-29T22:34:35","date_gmt":"2024-04-29T14:34:35","guid":{"rendered":"http:\/\/zestmag.com\/online\/?p=9183"},"modified":"2024-04-29T22:34:54","modified_gmt":"2024-04-29T14:34:54","slug":"study-reveals-cancer-vulnerabilities-in-popular-dog-breeds","status":"publish","type":"post","link":"https:\/\/zestmag.com\/online\/study-reveals-cancer-vulnerabilities-in-popular-dog-breeds\/","title":{"rendered":"Study reveals cancer vulnerabilities in popular dog breeds"},"content":{"rendered":"\n

Medium-sized dogs have a higher risk of developing cancer than the very largest or smallest breeds, according to a UC Riverside study.\u00a0<\/strong><\/p>\n\n\n\n

The study,\u00a0published in the Royal Society Open Science<\/a><\/em>, set out to test a model of how cancer begins. This model, called the multistage model, predicts that size is a risk factor for cancer. As it turns out, it is, but only when considering size variation within a single species.\u00a0<\/p>\n\n\n\n

It is common for cells to acquire errors or mutations as they divide and form copies of themselves. Bigger animals, and those that live longer, have more cells and a longer lifespan during which those cells divide.\u00a0 According to the multistage model, that means they have more opportunities to acquire mutations that eventually become cancer.<\/p><\/blockquote>\n\n\n\n

\u201cThe question that arises is why, then, don\u2019t we get more cancer than a mouse? We don\u2019t. There is no increase in cancer risk as animals increase in size from species to species,\u201d said UC Riverside evolutionary biologist and study author Leonard Nunney. <\/p>\n\n\n\n

However, this isn\u2019t true for animals of the same species. \u201cStudies on humans show that tall people get more cancer than short people. It\u2019s about a 10% increase over the baseline risk for every 10 centimeters in height,\u201d Nunney said.<\/p>\n\n\n\n

For more insight into these risk factors, Nunney required a species with a bigger difference between the smallest and biggest individuals. <\/p>\n\n\n\n

\u201cTesting this in dogs is even better because you can compare a tiny chihuahua to a great Dane. That\u2019s a 35-fold difference in size, and people can\u2019t come close to that,\u201d Nunney said. <\/p>\n\n\n\n

Surveying their mortality rates with three different data sets, Nunney found the smallest dogs, including Pomeranians, miniature pinschers, shih tzus and chihuahuas have about a 10% chance of dying from cancer.\u00a0<\/p><\/blockquote>\n\n\n\n

By comparison, many relatively large dogs, such as Burmese mountain dogs, have more than a 40% chance of death from cancer.   <\/p>\n\n\n\n

There were some outliers in the study. Flat-coated retrievers had the highest mortality from cancer, getting a type of sarcoma with higher frequency than they should have for their size. Scottish terriers seemed to get more cancer than other small dog breeds. \u201cTerriers in general get more cancer than expected for their size,\u201d Nunney said. In general, however, the study supports the idea that size is a major risk factor for cancer. <\/p>\n\n\n\n

However, the very largest breeds, such as great Danes, have less cancer than medium-sized breeds. That is because of a well-known but as yet unexplained phenomenon: the life expectancy of dogs gets shorter with size. <\/p>\n\n\n\n

\u201cFor every pound increase in typical breed size you lose about two weeks of life. A very big dog, you\u2019re lucky if they live past nine years, whereas small dogs can go about 14,\u201d Nunney said.  Cancer is predominantly a disease of old age so by having a reduced lifespan the largest dogs have a reduced cancer risk.<\/p>\n\n\n\n

According to the study, dog breeds are a clear fit with the multistage model of cancer acquisition that says larger size and longer lives offer more opportunities for cells to mutate. \u201cI was surprised how well dogs fit the model,\u201d Nunney said. \u201cBut that doesn\u2019t happen when you compare a mouse to an elephant or a human to a whale. So, does that undermine the model in some way?\u201d\u00a0<\/p><\/blockquote>\n\n\n\n

Nunney believes that an animal\u2019s ability to avoid cancer increases with the size of the species. \u201cMy argument is that preventing cancer is an evolving trait, so a whale will have more ways of preventing cancer than a mouse does,\u201d he said. <\/p>\n\n\n\n

While data are limited about the occurrences of cancer in whales, there is more information about rates in elephants, because they are kept in zoos. <\/p>\n\n\n\n

\u201cElephants don\u2019t get much cancer. Their ancestors, long before mastodons, were much smaller, so how, en route to today\u2019s size, did they avoid cancer?\u201d he wondered. \u201cThe secret to preventing cancer could lie within the biology of larger animals.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"

The smallest dogs, including Pomeranians, miniature pinschers, shih tzus and chihuahuas have about a 10% chance of dying from cancer. <\/p>\n","protected":false},"author":3,"featured_media":9184,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2432],"tags":[1410,1086,2238,1152],"class_list":["post-9183","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-pets","tag-household-pets","tag-pet","tag-pet-adoption","tag-pet-care"],"_links":{"self":[{"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/posts\/9183","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/comments?post=9183"}],"version-history":[{"count":1,"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/posts\/9183\/revisions"}],"predecessor-version":[{"id":9185,"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/posts\/9183\/revisions\/9185"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/media\/9184"}],"wp:attachment":[{"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/media?parent=9183"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/categories?post=9183"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zestmag.com\/online\/wp-json\/wp\/v2\/tags?post=9183"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}