As a pilot trial for the vaccination of game in African game parks against anthrax, trials with guinea-pigs were undertaken to vaccinate the animals orally against anthrax. The vaccine has been prepared with the Göettingen Bioreactor Technology obtaining sporulation in suspension. Guinea-pigs vaccinated orally and subcutaneously with the vaccine resisted a challenge of 1000 spores with a pathogen field strain isolated from elephants in Zambia. With a challenge dosis of 2500 spores orally and subcutaneously immunized animals died. A technique has been developed to identify anthrax organisms excreted with the faeces by means of gas chromatography.