peeing, they re going to be pooping, they re going to be bleeding because the edges are sharp and probably fighting in there. it is horrific. reporter: the vast majority of research monkeys die in a lab. very few wind up in a place like this. we are dealing with traumatized animals. reporter: a sanctuary for monkeys. liz tyson has a doctorate in animal welfare law. do you think long-tail macaques should be used in medical research? absolutely not. we need to work harder at finding alternatives. it s not to say we shouldn t do research blue it s to say we should by now doing different research. would you personally like to get to a point where you no longer need them? that s the ultimate goal. is that going to be possible? i think about how complex the system is. maybe years and years from now. reporter: until then the demand for one of human being s closest relatives to stand in for us in the lab is greater than ever. stephanie gosk, nbc news. we ll take a break. up nex
When a truck that was carrying 100 lab monkeys crashed in Pennsylvania, the public was warned not to approach any of the missing primates, who were being transported to a quarantine facility [.]