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991.
Pig farms with the annual capacity from five to 20 thousand head represent one of the crucial fields of agriculture influencing the environment in the CSFR. Daily production of large amounts of liquid excrements (150-300 m3), as a result of high concentrations of animals, poses not only technical but also sanitary problems closely related to the animal and man's health. In a long-term (267 days) field study the authors followed the development and survival of eggs of the model helminth Ascaris suum, contamination of the environment with the propagative stages of pig enteronematodes and possibility of their devitalization in a mechanico-chemico-biological waste-water treatment plant. Eggs of A. suum placed in the soil to the depth of 10 to 60 cm in November (1987) did not develop in winter months. Their development continued in spring months--at soil temperatures of 8.6 degrees C (at 5 cm depth) or 8.9 degrees C (at 20 cm depth). The embryonated eggs were found out at the beginning of the 20th decade of the experiment (May, 1988). The most positive samples on the investigated pig farm were found out in the vicinity of the central reservoir for waste water, showing the presence of both unembryonated and embryonated eggs of A. suum and Trichuris suis, with sporadic occurrence of Oesophagostomum dentatum L3 larvae. As demonstrated by our results, the tested waste-water treatment system complies only with the requirements of water management--with respect to the absence of the endoparasite propagative stages in the treated water.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
Z Hubálek J Pellantová K Hudec J Halouzka J Chytil P Machácek M Sebela F Kubícek 《Veterinární medicína》1991,36(1):57-63
Epizootic of wild water birds caused by the toxin Clostridium botulinum of C type occurred in extensive shallow artificial lakes of the Nové Mlyny dam system from May to October 1988 and later on from February to early April 1989. In total more than 3,000 dead or dying birds of 44 species were found, the following orders were prevailing: Anseriformes (56%), Lariformes (33%), Charadriiformes (6%) and Ralliformes (4%). Botulotoxin was detected at high concentrations in sarcophagic fly larvae of Calliphora vomitoria and Lucilia sericata which were collected in bird cadavers, but it was not found in different components of the aquatic environment (water, submersed vegetation, phytoplankton, zooplankton, Gastropoda, Crustacea, Oligochaeta, larvae of Odonata, Chironomidae and Ceratopogonidae). Future development of the epizootic situation in the Nové Mlyny artificial lakes will depend on the water level and meterological conditions in the critical period (May to September). 相似文献
993.
Two different egg based media, with and without the incorporation of sodium pyruvate, were used to isolate M. paratuberculosis from sheep, goat and cattle samples obtained at our laboratory for two years. Both media were adequate for bovine material, with a slightly improved isolation rate for Herrold's egg yolk medium incorporating sodium pyruvate; however, most of the small ruminant strains grew only on L?wenstein-Jensen medium without sodium pyruvate. Those results point out the need to use different media when working with small ruminant samples and provide further evidence for the existence of different varieties of M. paratuberculosis causing paratuberculosis in cattle and in small ruminants. 相似文献
994.
Pathogenesis of experimental combined infections with Isospora suis and rotavirus in conventional and gnotobiotic piglets 总被引:1,自引:0,他引:1
J Vítovec B Koudela M Kudweis J St?pánek B Smíd R Dvorák 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1991,38(3):215-226
51 gnotobiotic and 63 conventional, one-, or two-days-old piglets were divided into five groups and infected orally either with Isospora suis or rotavirus alone, or with both agents simultaneously or successively with alternative sequences and various intervals. 15 gnotobiotic and 10 conventional piglets served as controls. The development of small intestinal lesions after infection with I. suis was biphasic. The dominant alteration resulting from rotavirus infection was villus atrophy, considerably more pronounced and extensive in gnotobiotic than in conventional piglets. Synergistic action of I. suis and rotavirus was manifested both clinically, and morphologically. This action culminated at the time of the actual, or presumed development of merogony of I. suis, i.e. on DPI 3 to 5. The action develops only if the intestinal epithelium is damaged functionally and morphologically by a preceding rotavirus infection. It is concluded that the synergistic action is based on a competition of rotavirus and I. suis for mature, enzymatically active absorptive cells. 相似文献
995.
María Delclaux Covadonga Talavera Manuel López Jose Miguel Sánchez María Isabel García 《Journal of zoo and wildlife medicine》2002,33(3):283-285
A 17-mo-old captive-born female red panda (Ailurus fulgens fulgens) presented with a sudden onset of lameness in its left hind leg was diagnosed radiographically as having possible severe, bilateral Legg-Calve-Perthes disease with fracture of the great trochanter of the left femur. Surgical repair of the fracture was performed using pins and a tension band wire through a lateral approach to the hip. This is the first case reported at Madrid Zoo-Aquarium, where 63 individuals have been bred over 15 yr. 相似文献
996.
Despite intensive research and breeding efforts, the physiological and quantitative genetic bases of drought tolerance are still poorly understood. The comparison of results obtained from different sources is also complex, because different testing methods may lead to controversial conclusions. This report discusses various drought stress experiments (hydroponics and in soil) in which the plant tolerance was studied at different developmental stages. Tests were performed in the germination, seedling and adult plant stages on the parental lines of five well-known barley-mapping populations. The results suggest that drought tolerance is a stage-specific trait and changes during the life cycle. The effect of drought stress depended not only on the duration and intensity of water deficiency, but also on the developmental phase in which it began. To induce the same type of stress and to obtain comparable tolerance information from the replications, it is recommended that drought stress should be induced at the same growth stage. Correlations between the traits, commonly associated with improved drought resistance (high relative water content under stress, proline accumulation, osmoregulation) with stress tolerance indexes, are also presented, while the advantages and disadvantages of the most frequently used screening methods are discussed. 相似文献
997.
998.
999.
The hair and skin of 300 clinically healthy animals, 268 dogs and 32 cats, were examined mycologically. The method described by Mariat and Tapia (1966) was used for the examination, along with square pieces of the fitted carpet Kovral. The dermatophytes were isolated in 12 samples, all from the material taken from dogs. Trichophyton mentagrophytes was isolated six times, Microsporum canis four times, Trichophyton gallinae once, Trichophyton rubrum once. The origin of the dermatophyte Trichophyton gallinae, found in a village dog, was not determined. In one case of occurrence of the dermatophyte Trichophyton mentagrophytes in a dog the dermatophyte was probably transmitted from man to the dog. Microsporum canis was not proved to be the most frequent dermatophyte in dogs or cats in this country. 相似文献
1000.