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F Stĕrba

Publications and source records attributed to F Stĕrba.

9 recordsLinked to original sources
PubMed1989

[The significance of the incidence of coccidia of the Cryptosporidium species in the etiopathogenesis of neonatal diarrhea syndrome and enteritis in calves on the basis of simultaneous histopathologic and parasitologic studies].

In 1985, a histopathological examination was conducted in the ileum and a parasitological examination in the ileum and rectum of 345 emergency slaughtered calves. The pathogenic role of cryptosporidia was compared in two groups of calves: group A contained 184 calves (53.3%) with scours and enteritis, group B contained 161 calves (46.7%) with other types of disease. In both groups the calves were divided into four age categories: 7 to 10 days (7.8%), 11 to 14 days (29.3%), 15 to 21 days (53.0%), 22 days and older (9.9%). During the parallel examination by both methods, cryptosporidia were detected in 124 cases, i.e. at the total invasion extensity of 35.93%; in group A the cryptosporidia were found in 76 cases (22.02%) and in the group B in 48 cases (13.91%). As indicated by the results, cryptosporidiosis is a disease of polyfactorial origin and cryptosporidia must be taken into account as one of the enteropathogenic factors in the etiology of scours. It is confirmed by the positive findings of cryptosporidia in the calves of group B (29.81%) and the negative finding in group A (31.3%) that no clear relationship was demonstrated to exist between the positive findings of these protozoans and the clinical symptoms of the diseases and enteritis. The pathogenesis of cryptosporidiosis includes significant regressive changes in the microvillous layer and enterocytes, which were a common finding at heavy invasions. The total positivity of the findings of cryptosporidia in the ileum was significantly higher (by 14.8%) during the histopathological examination, as compared with the parasitological examination. Out of the total positive findings, 39 cases (31.5%) were demonstrated histopathologically. During the parasitological examination, the positivity of the findings of cryptosporidia was higher by 4.3% in the rectum than in the ileum. When there was conducted a parallel parasitological examination of the ileum and rectum, the total positivity was higher by 7.5% than at the histopathological examination in the ileum. The highest invasion extensity was found at the age of 7 to 10 days in both groups of calves. The highest invasion intensity was found at the age of 11 to 21 days in both groups. The age until the 21st day when the parasitosis is intensively spread is considered as the most dangerous age of the calves from the epizootological point of view. Cryptosporidia occurred all the year round, no characteristic seasonal patterns were observed. The total average invasion extensity of the 24 farms from where the calves came was 42.3%, its range being from 0 to 85.7%.

Animals↗
PubMed1987

[Use of the rose bengal test in the diagnosis of brucellosis in hares].

The diagnostic effectiveness of the Rose bengal test was verified in a set of 72 samples of the blood of hare shot in a focus of brucellosis; the blood was found to be serologically positive by the following methods: rapid agglutination with serum, surface fixation test, method of slow agglutination, and the complement fixation reaction. The Rose bengal test was found positive in 57 cases (79.17%), the surface agglutination test was positive in 60 cases (83.33%), rapid agglutination with serum in 41 cases (56.94%), slow agglutination in 55 cases (76.39%), and the complement-fixation reaction in 63 cases (87.50%). In nine cases (12.5%) a positive reaction was obtained only when the Rose bengal test was used. The results confirm that the Rose bengal test is a sensitive qualitative serological method of low technical and time requirements, suitable for routine diagnostic uses. In the field epizootological investigations in the foci of hare brucellosis, the Rose bengal test is a good screening serological method.

Agglutination Tests↗
PubMed1985

[The incidence and seasonal dynamics of yersinioses (Y. pseudotuberculosis, Y. enterocolitica), staphylococcoses and pasteurelloses in hares from 1976 to 1982].

In the years 1976-1982, 2071 dead hares from 64 districts of the Czech Socialist Republic were examined. The diseases under study killed 400 hares (19.3%). Pseudotuberculosis which killed 210 hares (10.14%) from 46 districts of the Czech Socialist Republic (71.9%) is considered as the most important hare population regulator. The highest occurrence of diseases was recorded in 1978. Pseudotuberculosis was of seasonal nature with the highest incidence in November and December. The second most widespread disease was pasteurellosis which killed 126 hares (6.08%) from 36 districts of the Czech Socialist Republic (56.3%). This disease dominated in 1976 and occurred seasonally, the highest incidence being recorded in autumn (November), winter (January) and spring (March). The infections induced by the bacteria Yersinia enterocolitica were not very widespread and killed 32 hares (1.45%) from 20 districts of the Czech Socialist Republic (31.3%). The highest number of cases was recorded in 1977. The monthly pattern of the development of the disease had three peaks - in November, January and April. Staphylococcosis killed 32 hares (1.54%) from 14 districts in the Czech Socialist Republic (21.9%). The highest number of cases was recorded in 1976. The disease occurred throughout the year with the highest incidence in November, April and February. This seasonal dynamics correlated positively with the worsened natural conditions for hare's life and with the reduction of the natural resistance of their organisms. A particular negative influence was exerted by bad climatic and food conditions, and by the monodietary type of nutrition in the autumn fasting period. The disease occurrence was also examined in relation to the animals' age; besides the infections with the Y. enterocolitica bacteria, the diseases prevailed in the adult individuals, which was partly due to the higher proportion of adult animals among the hares investigated.

Animals↗
PubMed1985

[The development of morphologic changes and the antibody response in guinea pigs experimentally infected with Brucella suis, biotype 2 bacteria].

Sixty-two guinea pigs were infected vaginally, perorally, intranasally, conjunctivally and subcutaneously with the bacteria B. suis, biotype 2. The inoculum contained 13.8.10(9) of brucellas in 1 ml of physiological solution. Subcutaneous infection lasted 151 days, the other types of infection 56 days. All types of infections resulted in brucellotic changes developing in relation to the type and duration of infection. The least marked changes were observed after peroral infection. Brucellosis was chronical and the changes in liver, spleen, lungs, and after subcutaneous infection also in regional lymphoglandulae, were found out incessantly. Microscopically these changes were histiocytic granulomas. The pathogenesis of brucellosis process in guinea pig organism is influenced primarily by haematogenous propagation. The highest serological reactivity was caused by subcutaneous infection, the lowest by peroral infection. In the course of different types of infection the titres of agglutination and complement-fixation antibodies varied and the highest values were recorded between the 21st and 56th day. The diagnostic effectiveness of the surface fixation test was verified and no decrease in its sensitivity, not even in the chronic phase of infection, was observed. An incomplete correlation between morphological changes and serological reactivity in guinea pigs was detected. The highest number of Brucella infections was identified by histopathological examination which helped to reveal the initial stages of granulomas at the time when specific antibodies were not yet determined by serological tests.

Animals↗
PubMed1984

[Brucellosis in rabbits induced by an experimental infection with Brucella suis germs].

Hares were experimentally infected with Brucella suis germs, biotype 2, to study the development of morphological changes in the organs. It was demonstrated that conjunctival and intranasal infection caused morphological brucellosis changes in liver. After conjunctival infection affections were observed in 16 days, and in 27 days after intranasal infection. The morphology of changes did not differ from those occurring in spontaneous brucellosis. The results of morphological examination corresponded to the serological results. It was proved by the results of the experiment that the course of brucellosis could be chronic and that in the process of the natural infection of hares with Brucella suis germs the conjunctival and intranasal modes of infection played an important role. Hares were highly sensitive and responsive to the conditions of the environment where experimental infection was performed. In laboratory conditions the health condition and functions of the organs of hares were impaired by a complex of negative, mainly psychogenic stress factors, which resulted in the death of hares and the experiment had to be finished prematurely on the 41st day after infection.

Animals↗
PubMed1984

[Morphological changes in brucellosis in guinea pigs due to experimental infection with Brucella suis].

Sixty-four guinea-pigs were infected with the germs of Brucella suis. biotype 2 via the vaginal, peroral, intranasal, conjunctival and subcutaneous routes. In the subcutaneous infection the length of the trial was 151 days and in the other methods of infection 56 days. As found, guinea-pigs are highly sensitive and brucellosis lesions were detected in all cases. Brucellosis was chronical and spread locally in the guinea-pigs. In the haematogenic spreading of the disease, lesions were constantly recorded in liver, spleen and lungs. In the cases of subcutaneous infection lesions were also observed in regional lymph nodes at the places of infection. The lesions had amorphous structure and regular borders. The lesions were characterized by pronounced exudation and the exudate was subject to caseous necrosis, followed by colliquation. Secondary central colliquation was regularly observed in older granulomas, so that colliquation is considered as a characteristic morphological trait of brucellosis process in guinea-pigs. Histiocytary granuloma constituted the microscopic basis of the lesions. In older granulomas the central necroses were wide and contained a large amount of nuclear detritus, owing to the karyorhexis of cells, mainly neutrophiles. In the necroses of caseous type lipoid droplets were found and calcification was observed on the 151st day. Big cells of Langhans type occurred sometimes in the histiocytary layer of granulomas; they were present most frequently in the lesions affecting lymph nodes. Interstitial pneumonia was a characteristic symptom in liver and big cells of Sternberg type were found in the granulomas. Follicular tumor was constantly observed in spleens. Morphologically detectable lesions first developed in liver after about 7 days from conjunctival infection and subcutaneous infection, after 21 days from vaginal and intranasal infection, and after 28 days from peroral infection. In the case of subcutaneous infection, granulomas were found in the regional lymph nodes on the 14th day. The most expressive lesions in organs, mainly liver, were found from the 49th to 56th day from infection.

Animals↗
PubMed1983

[Differential pathomorphologic diagnosis of brucellosis in hares].

The examination comprised 656 cases of brucellosis, 208 cases of pseudotuberculosis, 31 cases of yersiniosis, 13 cases of tularemia and 120 cases of pasteurellosis. In brucellosis, changes in liver, spleen and sexual organs prevailed. The macroscopy of the changes was typical. A histiocytic granuloma of tuberculoid type was found by histological examination. Owing to caryolysis, the central necrosis of granulomata contained a conspicuously small amount of nuclear detritus, and big cells of Langhans type were found in the histiocytic layer. A layer of round-cell elements constantly occurred on the periphery of the necrosis and peripheral fibrotization was observed in older granulomata. Pyogenic component was almost absent. Pseudotuberculosis and yersiniosis were characterized by septic tumour of the spleen and alterations in liver, lungs, kidneys, and the terminal section of ileum. In pseudotuberculosis necrotic changes occurred in bone marrow and in processus vermiformis. The changes were histologically limited by the formation of granulomata and necrosis with characteristic karyorrhexis and with tht occurrence of masses of bacteria in the necroses. Neutrophiles were constantly found to be present in the changes, whereas peripheral fibrotization was not typical. In tularemia, besides spleen tumour, alterations in lungs prevailed, having a vitreously smoky appearance, bacon-like on cross section. From the histological point of view, a histiocytic granuloma of tuberculoid type was involved. Its only differences from brucellosis were the larger content of nuclear detritus owing to karyorrhexis and the occurrence of erythrocytes in the lung alterations where marked peribronchial and perivascular infiltrates were present. The typical location of spleen alterations was the periphery of Malpighian corpuscles. Staphylococcosis was differentiated by a purulent nature of the changes and pasteurellosis by a constant finding of pneumonias and tracheitis.

Animals↗
PubMed1982

[Pathomorphological changes in brucellosis in hares].

The morphology of 645 cases of brucellosis in hares evoked by the germs of Brucella suis, biotype 2, is described. Brucellosis had the character of chronic granulomatous process with prevailing changes in liver, spleen and in sex organs of hares of both sexes. In the sex organs of sexually immature hares the changes were detected in 2.26% of animals. The granuloma macroscopy was typical and was most discernible in liver. In the organs there prevailed solitary granulomas of the pea size. In testes two types of changes were found--coagulation necrosis and granulomatous form. In uterus node conglomerates in parametrium and mesometrium were typical. By histological analysis histiocyte granuloma of tuberculoid type with typical arrangement of layers was found. Central caseous necrosis was characterised by lesser nuclear detritus due to caryolysis. In the histiocyte layer of granulomas, an inconstant occurrence of macrocells of the Langhans type was observed. The layer of spherical cellular elements was more pronounced in smaller granulomas, in uterus and testes plasma cells prevailed. The eosinophil presence in the changed parts was low, their larger occurrence was found only in uterus, muscle lymph glands and in osteomuscular granulomas. In larger granulomas peripheral was always visible. Pyogenic component in granulomas was almost always absent.

Animals↗