About 30 animal-rights activists held a midday protest Sunday outside the California National Primate Research Center at UC Davis. From left are Veronica Perez, Catherine Vade Bon Coeur and Linda Middlesworth. The protesters sought to highlight the addition of a new smoke exposure test, part of an $18 million respiratory diseases laboratory opened in February, and monkey deaths at the center. Federal inspectors last cited the center in October after UCD self-reported the death of an animal that got caught in a squeeze-door mechanism. The center is home to about 4,900 monkeys, most of them rhesus macaques. About 65 percent of them live outside in 24 half-acre corrals. Research in the new building will focus on chronic obstructive pulmonary disease, exposure to secondhand smoke and air pollution, childhood asthma and infectious diseases, including H1N1 influenza in infants.