Producers. They’re usually producers.
Explanation:
They can't tranfuse because they will have an ABO incompatibility reaction. In an ABO incompatibility reaction, your immune system attacks the new blood cells and destroys them
If you have type AB you have both A and B antigens. Therefore you have B too that's why you can't only tranfuse with A after all you have to have to have both types.
It's the definition of a SPECIES.
Those animals are from the same species.
The answer is Psychoneuroimmunology.
This is the study pf the interactions among behavioral, neural and endoicrine, and immune processes. The brain communicates with the immune system through the autonomic nervous system and neuroendocrine activitry.