Collecting blood samples from zoo animals can prove to be a difficult task, often requiring sedation. Small animals are especially tricky because finding a vein from which to draw blood can be nearly impossible. The kissing bug solves those problems—it's any one of 130 species of small, blood-sucking insects belonging to the sub-family Triatominae. Like most blood-suckers, the kissing bug releases a pain-reducing enzyme when it bites, effectively anesthetizing the area at the same time as the bite. The bug is at the center of a pilot project in two zoos in the UK under the umbrella of a study which originated in Germany. The insects are bred in a sterile lab, then put against an animal's hide under a container in which they are caught when they have finished feeding. They are ultimately killed to collect the blood samples. The technique is so far proving to be a welcome non-invasive alternative.