THE ISOLATION OF ANAEROBIC GRAM‐NEGATIVE BACTERIA FROM POULTRY REARED WITH AND WITHOUT ANTIBIOTIC SUPPLEMENTS

Abstract

Summary A number of methods advocated for the isolation of ‘bacteroides’ have been tested. By using an ethyl violet–azide agar medium under strictly anaerobic conditions, as many as 10 8 /g of a group of obligately anaerobic Gram‐negative bacteria were detected in the caeca of chickens. Freshly isolated organisms from chlortetracycline fed chickens showed a slightly greater resistance to chlortetracycline than those isolated from the control birds, but there was little difference after further subculture.