The testing cages were breeding cages of wood, measuring 70 x 45 x 35 cm, with dispensers for food, water and
grit and having wire-mesh front doors. Isolation cages were double-width hanging rat-cages in racks. Breeding
and isolation cages were kept in separate rooms. Lights were clock-controlled (Tork) to turn on at 06.00 hours
and off at 20.00 hours E.S.T. Temperature was generally kept between 22° and 24°C.