{HEAD ~ Male Hartley guinea pigs} from Charles River, weighing {TAIL ~ 250 275 grams} on arrival and 300 600 grams at testing, serve as subjects in the experiment 
weighing
{ HEAD ~ Male Hartley guinea pigs } from Charles River , weighing { TAIL ~ 250 275 grams } on arrival and 300 600 grams at testing , serve as subjects in the experiment
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH