The species that has the most complex immune system is humans.
Humans immune systems are the most complex when it comes to immune systems.
And Africans tend to have stronger immune system than Americans and Europeans.
All animals do not have the same immune system as immunity varies between different animal groups but they always contain an innate immune system which can act fast and often very effectively against a wide range of distinct pathogens including eukaryotic parasites, fungi, bacteria, viruses etc.
Different species of animals also have evolved different immune systems and solutions which are not necessarily genetically related although they serve a similar function.
Ostriches are the animal that has the best immune system and the most powerful immune system.
The animal that has a poor immune system are cheetahs which are categorized as a vulnerable species, partly because they have been considered to be prone to diseases due to their supposed weak immune system.
The animal that has the closest immune system to humans is the porcine or pig.
Porcines also known as pigs have an immune system that resembles humans for more than 80 percent of analyzed parameters.
The immune systems of porcine or pig and swine and humans are similar in their anatomy, organization and immune responses.
The pig's immune response is more similar to human (80%) than mouse (10%) and this, along with its size, makes it a more suitable and clinically relevant model for comparative immunology studies for human diseases.
The reproductive systems between pigs and humans are also very similar.
Urethra, ovaries, uterine tubes, labia, mesenteries, testes, epididymis, vas deferens, inguinal canal, prostate gland, etc.
And these structures are basically the same in the fetal pig and human.
The anatomical structure and function of the cardiovascular system, the gastrointestinal tract, and the pancreas of the pig are very similar to humans making them ideal models for investigating diseases related to these systems.
Pigs have some notable difference when compared to humans.
pigs which are also called swine or hog or porcine, are an omnivorous, domesticated, even-toed, hoofed mammal.
It is named the domestic pig when distinguishing it from other members of the genus Sus.
It is considered a subspecies of Sus scrofa by some authorities, but as a distinct species by others.