Let's start with XenoTransplantations. XenoTransplantations is when a human heart won't work properly so they have to replace it. However, if there aren't any human donors, they use pigs hearts.
This is a pig's heart. It is nearly a perfect match to a human's heart. However, even though it's a good source of a heart, there aren't so many people that agree with this method.
XenoTransplantations have multiple beneficial factors but also have many negative factors. Some religions don't agree with this method, others accept this method. Time to write!
XenoTransplantations are a really useful and renewable source of useful hearts that save hundreds of lives a year! If no human donors are available, they will resort to going to a pig pen.
Within the Pig pen, they execute the healthiest pigs so the risk of rejection and internal infection isn't too high. However there are always negative things about XenoTransplantations...
Even though there isn't such a high chance of infection or rejection, the percentage is still hit enough for it to still be a common form of death. Within a few weeks or so of the operation.
Some people survive the operation, well, most people, however if the heart isn't sterilised before the operation occurs, diseases will spread through the disabled defense mechanism.
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