Anti-quota doctors in Post Graduate Institute of Medical Education and Research (PGIMER) went on a mass casual leave today to protest the bill providing quota for OBCs in government-aided higher centres of learning."Yesterday, as a mark of protest we wore black badges and today all resident doctors of PGIMER have proceeded on mass casual," a spokesman of Youth for Equality, spearheading the anti-quota agitation, Subh Mohan Singh said.The doctors, who got support from the students of the Punjab Engineering College here, also took out a rally raising slogans against the government for going ahead to implement 27% quota for OBCs in higher centres of learning.Shubh Mohan Singh said they had given advance notice to the PGI authorities about their decision to go on mass casual leave.PGI officials maintained that critical services were being maintained without any inconvenience to the patients.Though OPDs were partially affected, PGI authorities said "faculty is chipping in and we are trying to maintain our regular services".