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OKLAHOMA CITY – After 10 training sessions, Elok, the 17-year-old Sumatran orangutan, became to first great ape to voluntarily participate in a blood sample collection at the Oklahoma City Zoo.

For the past six months, Pace Frank, the lead Great Escape caretaker, has been working with Elok and familiarizing him to a blood collection sleeve.

Pace, along with the Zoo’s maintenance department, designed a custom sleeve that would hold Elok’s arm safely, so the veterinary technicians would be able collect a blood sample.

The new sleeve was installed in April, and Elok began sticking his arm in it immediately.

According to zoo officials, Elok spent his training sessions watching the process and engaging with staff. He was rewarded for his participation by getting his favorite juice and snacks.

And on May 26, veterinary technician Liz McCrae, was able to collect a voluntary blood sample from Elok. It was the first blood sample collected through behavioral training with a great ape at the Oklahoma City Zoo.

Zoo officials say, historically, blood samples have only been collected from most of the large animals during anesthetic exams. The team was been working to obtain “blood samples voluntarily through operant conditioning, in an effort to work towards decreasing anesthesia time in collection animals.”

Staff will continue weekly training sessions with Elok, with the goal of collecting samples monthly.

They will be used to monitor his health as he ages, and his blood samples will be stored for future research projects.