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Biomedical subjects

D Savov

Publications and source records attributed to D Savov.

11 recordsLinked to original sources
PubMed1978

[Resistance of E. coli and bacteria of the genus Proteus to the thermal processing of perishable meat products].

Experiments were carried out in six meat combines to establish the devitalization of Escherichia coli and bacteria of the Proteus genus at the thermal treatment of perishable meat products. Seventy series of experiments were conducted with 16 types of meat products of a different structure (homogenic and heterogenic), varying composition unequal diameter of the casings (3-4 am, 5-6 am, and 7-8 am), and different type of the latter--natural, paper, and cutis-lika. Twenty-four-hour agar cultures at a density of 10(5)-10(7) bacteria per gram of meat mass were used. In a series of experiments the temperature was dermined of the finished product when it reached 68 degrees C; in another group--after smoking and at various intervals during cooking; and in a third group of experiments the temperature was fillowed up during the entire thermal process, using thermo pairs. Studied was the heat resistance of the organisms tested under laboratory conditions, using the thermal curve in the production of meat products. The samples were investigated at the 24th, and 48th hour, and on the 5th day of room temperature storage. Results showed that devitalization of these organisms set in at 63 degrees C (E. coli) and 60 degrees (Proteus). The composition and homogeneity of the meat mass and the diameter of casings were found to have no effect on the heat resistance of these organisms.

Animals↗
PubMed1977

[Lysogeny in Escherichia coli isolated from birds and the spectrum of the lytic action of isolated phage].

Studies was the lysogenicity in a total of 70 strains of Escherichia coli isolated from birds. As many as 19 lysogeneic strains were isolated, yielding 19 phages that had the signature of lysogenic strains. Two serologic groups of phages were established by means of the neutralization reaction. It was found that phages 30 and 229, representing the two serologic groups of bacteriophages could lyse up to 44 per cent of the E. coli strains isolated from birds, 7 per cent of those isolated from calves, and 4 per cent of those from pigs. Out of 74 Salmonella strains, belonging to ten species, the same phages lysed two strains of Salmonella newport and 1 strain of Salmonella anatum. It is believed that phage lysis could be used to establish the source of infection and to evaluate the effectiveness of the prophylactic measures applied, incl. disinfection.

Animals↗
PubMed1977

[Antibody dynamics in growing birds experimentally infected or naturally sick with white diarrhea].

Serologic studies were carried out with growing birds, aged 37-70 days, experimentally and spontaneously infected with Salmonella gallinarum and Salmonella pullorum, respectively. More positively reacting birds were found by means of the whole-blood agglutination reaction with typhoid-pullorum test than in the study of the same birds when aged 6-7 months. The investigation of birds when young is also advantageous in that there are no losses of eggs, it is more readily carried out, and the infected flocks could as early as the first selection be intended for market production, being replaced with healthy flocks. It is believed that certain changes in the programme for the control on pedigree and reproduction flocks would be purposeful, the first investigation for pullorum disease being carried out when the birds are aged 40-70 days and not when 6-7 months old.

Agglutinins↗
PubMed1976

[Experience in controlling the Salmonella carrier state on a pedigree poultry breeding farm].

Systematic microbiologic control was carried out in the 1972-1975 period on an elite poultry farm whereas from the 23,724 samples studied, taken from objects of the epizootic chain forage-birds-hatchery, 78 cultures of Salmonella organisms of 14 species or 0.32 per cent of the total number of samples were isolated. A trend was observed toward the year-to-year drop in the number of positive findings of Salmonellae, and by the end of 1975 the results were negative. This fact was backed by the investigations in the poultry dressing combines throughout the country that have received the parental forms of birds from the sanated elite poultry farm. Established was vertical (congenital) transmission of Salmonella enteritidis, and using the typhoid-pullorosis test all carrier birds were detected and eliminated. Thus serologically were followed up and eliminated the hidden sources of infection among the flocks on the elite poultry farm. The alimentary mechanism of infection transmission (horizontally with the chain forage-birds was discontinued through the storage of feed mixtures packed in bags (not in bulk). The chain birds-hatchery was interrupted by means of fumigation, the eggs being treated up to the second hour following laying, and then subjected to four subsequent treatment with disinfectants up to hatching. The environment was sanated by three-fold disinfections every sixth day with lysol, formalin or veraform, anf fumigation with formaldehyde vapours, resulting in 100 per cent effectiveness. This was demonstrated many times bacteriologically. The overall observation of hygiene measures contributed to the sanation of the elite farm. The parallel examination of personnel on the farm made by organs of the Hygiene and Epidemiologic Inspection detected a female worker that acted as a carrier of S. enteritidis. Upon her elimination the complex of measures for the study and complete sanation of the farm was considered fulfilled.

Animals↗
PubMed1975

[Resistance of tuberculosis mycobacteria in raw-dried and raw-fumigated sausages].

Studied was the resistance of Mycobacterium tuberculosis, Mycobact. bovinum, and Mycobact. avium in the nonperishable raw-dried and raw-fumigated saussages Koprivshtenska and Troyanska loukanka and Gornooryahovskanadenitsa, produced according to the requirements of the Bulgarian State Standards and the technologic instructions. It was found that the viability and pathogenicity of the tuberculosis mycobacteria in the raw-dried loukankas persist up to the 180th day from contamination, and in the raw-fumigated loukankas they were established up to the 150th day. The survival of bacteria in these saussages during long storage depended on the count of the microbial cells in the meat mass. At 120,000 cells per one gram of meat mass, some bacteria were found up to the 180th day, while at 1200 cells these persisted up to the 150th day.

Bulgaria↗