Would you believe me if I said an animal in the wild actually had a low immune system? It doesn’t make much sense since animals in the wild are near so many diseases and attract sickness constantly. But yes its true, cheetahs the Earth’s fastest land animals are known to have weak immune systems. The strangest part about it is that even with the weak immune systems, cheetahs still stay fairly healthy through their lives.
Cheetahs have a low major histocompatibility complex(MHC) variability, which should result in a weak immune system. MHC is a genome that regulates the immune system of the animal. Even with a low MHC for cheetahs they still seem to be fairly healthy creatures. Cheetahs have three parts to their immune system, 1. being the constitutive innate immune system, 2. being the induced innate immune system, and lastly 3. the adaptive immune system.
A scientific study was tested on a group of cheetahs to explain how they stay healthy with a low MHC level. This test was also conducted on leopards to compare the results of the cheetah to the leopards, who have higher MHC levels and live in the same regions as cheetahs. Scientists conducted 6 immunological tests on both the cheetahs and the leopards. The results of the tests showed that cheetahs have higher first line of defense immune systems to compensate for their low MHC levels. According to the tests done, “Cheetahs have apparently developed a way to successfully fight against pathogens despite their low genetic variability in their MHC.” (2017, Sonja)
And with this development the cheetah is able to survive in the wild, even with a critically low immune system. Though this low immune system for the cheetah does bring attention, because it could possibly be the cause of their extinction, if the cheetah ever got paired with a disease its weak immune system couldn’t fight off. More tests will follow in the coming future, as this was only the first test to be done on the topic that different species can have varying immune system components.
Sonja K. Heinrich, Heribert Hofer, Alexandre Courtiol, Jörg Melzheimer, Martin Dehnhard, Gábor Á. Czirják, Bettina Wachter. Cheetahs have a stronger constitutive innate immunity than leopards. Scientific Reports, 2017; 7: 44837 DOI: 10.1038/srep44837