In either the yolk sac or the allantoic assays, fluid from each embryonated egg which contained a non-viable embryo was plated onto two blood agar plates.One plate was incubated aerobically at 36°C ± 1°C. The second plate was incubated anaerobically at 36°C ± 1°C. The plates were examined for growth after a minimum of 24 hours.All animals were fed the following diet ad libitum:Guinea pigs - Teklad Certified Guinea Pig Chow.Mice - Agway Prolab (autoclavable)Water was supplied ad libitum via water bottles.Water for guinea pigs was disinfected with 7 ppm chlorine.Water for mice was autoclaved.Bedding - Bed-o-Cobs, Anderson Cob Mills.Cages were changed as necessary, usually twice per week.