[Isolation and characteristics of nutritional variants of streptococci of animal origin].

Four strains of nutritionally variant streptococci (NVS) were isolated from the milk of mastitic cows and one strain from the lungs of a laboratory Norway rat which died from suppurative pneumonia. In primary cultivation NVS grew aerobically and anaerobically within 48-hour incubation at a temperature of 37 degrees C as minute nonhemolytic satellite colonies around a previously overlaid S. aureus strain or around other gram-positive and gram-negative bacteria. In the first subcultures NVS were growing in nutrient media enriched with 10% bovine serum and 5% staphylococcal filtrate, or 0.02% to 0.002% pyridoxal hydrochloride. All isolates did not grow in presence of 10%, 40% bile, and 6.5% of sodium chloride, neither did they grow at a temperature of 45 degrees C, they did not hydrolyze sodium hippurate, esculin, arginine, they did not produce levane and dextran from saccharose, they produced acid from mannitol, sorbitol, inulin, lactose, raffinose, trehalose, glucose, saccharose and maltose. Two strains produced acid from xylose and four strains from salicin. The strains isolated from mastitis did not have different biochemical properties from those isolated from a laboratory Norway rat with pneumonia. All strains of NVS were sensitive to chloramphenicol, ampicillin, gentamycin, lincomycin and cephalothin, four strains were sensitive to erythromycin and tyrosine, two to penicillin and one to streptomycin, oxytetracycline, chlortetracycline and novobiocin. All strains were resistant to neomycin, tetracycline, oxacillin and sulphonamides. The antigen prepared from the isolated strains by the method of Fuller did not react with any streptococcal group serum A-Z.