[Comparative studies of methods for the bacteriological diagnosis of mastitis in cows]

Comparative studies were carried out on some methods and nutrient media used for the isolation and identification of mastitis causative agents. Milk from normal andmastitis-affected udder quarters was aseptically sampled and treated under various conditions. Individual samples were simultaneously seeded in different media. The following conclusions were drawn: 1. Milk samples for the diagnosis of mastitis of a subclinical character can be taken at the beginning and at the end of milking. 2. Direct seedings of milk have equal diagnostic value as those of the sediment. With the former the process of bacteriologic treatment of the samples is shortened in time, and the isolation and differentiation of the mastitis agents is rendered feasible. 3. At the present etiologic structure of the subclinical types of mastitis in this country most suitable has proved the blood agar medium in which almost all mastitis causative agents can be demonstrated. 4. Kartashova's medium and the TKT-medium possess a pronounced selectivity with special reference to streptococci and have higher diagnostic value for farms where streptococcus mastitis is prevailing.