ConocoPhillips first-quarter profit, output lower Thu Apr 25, 2013 8:20am EDT (Reuters) - ConocoPhillips (COP.N) reported lower quarterly earnings on Thursday as oil and natural gas production edged down along with crude prices. Oil and gas output from continuing operations was 1.56 million barrels oil equivalent (boe) per day, down slightly from 1.58 million boe per day a year earlier. Reporting by Anna Driver; Editing by John Wallace