Tryptone 5 g Proteose peptone 20 g NaCl 5 g Agar 20 g Distilled water 1 liter
Autoclave 15 min at 121°C. Adjust pH to 7.0 ± 0.2.
2 Fresh Eggs
Treatment of eggs. Wash 2 fresh eggs with stiff brush and drain. Soak eggs in 70% ethanol for 1 h. Crack eggs aseptically. Retain yolks. Drain contents of yolk sacs into sterile stoppered graduate and discard sacs. Add yolk to equal volume of sterile 0.85% saline. Invert graduate several times to mix. Egg yolk emulsion (50%) is available commercially.
Preparation of medium. To 1 liter melted medium (48-50°C) add 80 ml yolk-saline mixture (available from Difco as Bacto Egg Yolk Enrichment 50%), and mix. Pour plates immediately. After solidification dry 2-3 days at ambient temperature or at 35°C for 24 h. Check plates for contamination before use. After drying, plates may be stored for a short period in refrigerator.