Sam, if you are worried about blood libels, trying to fight lies by covering up truths will never work in this information age.
The blood libels were false because they represented a superstitious and bigoted way to interpret situations such a child gone missing, that completely ignored due process, relied on unreliable evidence, and supported collective cruel and unusual punishment.
Overstating the argument by saying “and blood happens to be chazer treif” is not productive in this age where everyone can (and generally will, eventually) find everything out. On the contrary, an overstated argument is a lost argument. Besides, even if it were true, it is hardly the main motivation one might have to refrain from killing little children.