Genetic relationship among bacteria classified as vibrios.

Genetic relatedness among six bacterial strains currently classified as vibrios was determined by biochemical tests, deoxyribonucleic acid base composition analysis, and the detection of nucleic acid homology by the membrane filter method. Varying degrees of genetic homology existed among vibrios having similar base compositions. The bovine isolate which had a substantially different per cent guanine plus cytosine content was shown to be genetically different from the remaining vibrio strains.

Mycoplasma: isolation from prepuce and semen of bulls.

Mycoplasmas were isolated from the prepuce of 12 of 45 bulls and the semen of 2 of the 12 preputial-positive animals, and also from the semen of 1 of the 33 bulls which had not yielded mycoplasmas in the preputial sample. It appears, therefore, necessary to examine both preputial material and semen to detect potential shedders of Mycoplasma. Addition of fresh yeast extract to a solid medium of Bacto PPLO agar + Bacto PPLO serum fraction (1 %) + horse blood (5 %), and 0.

Mycoplasma: nutritional studies of laboratory strains.

Growth of 12 laboratory strains of Mycoplasma isolated from cattle, chicken, goat, man and sewage were studied on 20 different solid mediums and 9 liquid mediums. Growth on solid mediums was evaluated on the basis of appearance of visible colonies, while growth in liquid mediums was determined by light transmission technique. A solid medium of Bacto PPLO agar + Bacto PPLO serum fraction (1 %) + horse blood (5 %), and 0.

GASEOUS ENVIRONMENT AND GROWTH OF MICROAEROPHILIC VIBRIOS.

Fletcher, R. D. (University of Connecticut, Storrs), and W.

CHEMICALLY DEFINED MEDIUM FOR SOME MICROAEROPHILIC VIBRIOS.

Fletcher, R. D. (University of Connecticut, Storrs) and W.