" The sacrificial animal used by most Middle Eastern peoplewas the wild boar, so the Sirians chose to use it as the basis for this new animal hybrid. Hunan genetics weremixed with those of the wild boar to produce the domesticated pig. This animal was served daily to the Bluebloods as a method of maintaining,temporarily, their human form...
because the domesticated pig is a combination of human and animal genetics, eating it is a form of cannabilism" Stewart Swerdlow
And why there would be adverse reactions with grafting to our primate cousins
 http://www.xenodiaries.org/