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Biomedical subjects

M Halasa

Publications and source records attributed to M Halasa.

4 recordsLinked to original sources

[The etiology of foul brood].

Five hundred and thirty-six samples of honeycombs were examined in a laboratory in the years 1971-1974. In all the samples clinically determined as the foul brood, B. alvei was isolated as a pure culture, and enterococci, or both microorganisms were isolated in mixed form. Twenty-five strains of the isolated streptococci were analyzed microbiologically and biochemically; on the basis of their culture and biochemical characteristics five strains were designated as Streptococcus faecalis, 14 strains as Streptococcus faecalis var. liquefaciens, five strains as Streptococcus faecium and one strain as Streptococcus durans. After checking the used taxonomic key of the culture and biochemical classification of B. alvei it may be stated that the culture and biochemical characteristics are stable. The strains of B. alvei (very dried strains), which persisted in the dried slant meat-peptone agar, were viable under the laboratory conditions, which proves the high resistance of the spores to the environment.

Animals

[Study of the spiral and spindle-shaped formations in cultures of Bacillus larvae (White 1906) causing foulbrood in bees].

The authors have been studying the bacterial diseases of the brood for a fairly long time. American and European foul brood has been studied with the highest attention. Cultures of Bacillus larvae (White, 1906) were examined both in freshly isolated strains and in collection strains of this micro-organism. In cases of foul brood, the pathological material was found to contain not only the typical rods of B. larvae but also immobile spiral forms which are usually referred to in literature as fragments or developmental forms of B. larvae. These spiral forms were found to constitute spindle-shaped formations in the culture of B. larvae; the multiplication of these spindles depends on the presence of the rods of B. larvae and their development and reproduction can be observed on wet gelatine agar in a Petri dish turned upside down under a normal microscope (10 X 10 magnification). In the combined liquid medium, used in the experiments, these formations disintegrate into immobile spirals; if re-cultivated on a solid medium they re-assume their spindle shape with transverse meridian arrangement (in different amounts). Staining for proving the presence of nucleic acids does not eliminate the possibility of these formations being separate micro-organisms which cannot be stained by current staining methods but can be represented by the contrast method according to Burri, or by silvering according to Klein. The authors succeeded to separate these micro-organisms, but without the rods of B. larvae the colonies of these formations are feeble.

Animals

[Comparison of nutrient media for isolation of microflora in swine dysentery].

The usability of five nutrient media - three kinds of spirolate media, thioglycolate medium and brain hearth medium - suitable for the isolation of Vibrio coli and germs similar to borrelia isolated from pigs affected by dysentery, and vibria isolated from cattle, was compared in the study. The results of comparison show that fresh-prepared substrates must be used bor the isolation of the mentioned germs in all cases and a corresponding medium must be provided. The modified spirolate media prepared from inland and imported ingredients were suitable for the isolation of the mentioned microorganisms even in the case of their use as selective media after enrichment with antibiotics. The spirolate media and thioglycolator agar were not found suitable for maintaining the strains of germs similar to borrelia due to the quick production of involution forms and the result dying of the strains. Thenutrient solution prepared as the brain hearth inf. Oxoid blood agar is very suitable for the isolation as well as maintenance of strains.

Animals