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991.
Thirty-five Pasteurella haemolytica strains were isolated in Hungary from goat carcasses sent for postmortem examination from two farms with large goat flocks. All strains belonged to biotype A and with the exception of one strain of serotype A8 they belonged to serotype A2. No untypable strains were found by the indirect haemagglutination test.  相似文献   
992.
The authors examined 585 samples from 92 mares of 2 studs and 346 nasal swabs taken from their foals for the presence of mycoplasmas. The positive rates of mares and foals were 81.5% and 71.7%, respectively, with positivity of samples being variable. Clinical symptoms developed in 2-4 waves and lasted 3-7 days, with intervals of 7-12 days. The disease started in April among foals born in February, at an average age of 88 days. Later on, the average age of the affected foals decreased. There was a correlation between presence of mycoplasmas in nasal cavity and disease of foals.  相似文献   
993.
In 15 selected stocks in the Strakonice district, 507 slaughter pigs, 708 small terrestric mammals and 110 free-living birds were examined in a two-year period (1986-1987) to study the occurrence of carriers of yersiniae and their elimination. Rectal smears from 243 persons working in livestock production were examined in the same way. Standard bacteriological methods, recent examination procedures (Aulisio et al., 1980; Aldová, 1981) and a diagnostic antiserum (03 IMUNA Sarisské Michalany) were used for the examination. The following results were obtained: In pigs: 1. yersiniae were detected in 65 cases (12.8%); of this, in 31 cases they occurred in the tonsils, in 35 cases in ileum, and twice in the ileocaecal lymph nodes. 2. Epidemiologically significant Y. enterocolitica 4;03 was detected in 28 cases (5.5%); of this, 22 times in the tonsils, 7 times in ileum, and once in the ileocaecal lymph nodes. 3. The seasonal nature of the occurrence of yersiniae was confirmed in 1986, with maxima in winter-spring, but in 1987 their occurrence declined substantially to less than a quarter. In the small mammals, yersiniae were detected 28 times (4%); of this, 7 times in common field mouse, 11 times in common vole, 5 times in house mouse, twice in shrew, once in Apodemus flavicollis, and once in Apodemus sp. 2. Y. enterocolitica 4;03 was detected twice (0.26%), both cases in the house mouse. Other results: 1. In all the 110 free-living birds the examination for yersiniae had a negative result; 2. in the rectal smears of 243 persons employed in livestock production, yersiniae were identified twice (0.8%)--in one case Y. enterocolitica 1, in the other Y. enterocolitica biovars 1 and 2.  相似文献   
994.
The authors of this paper have produced live vaccine to cope with infectious agalactia in goat. The vaccine (culture) was used on 360, 924 goats kept on ajmaks in Bajanchongor and Gobi-Altaj, in 1986. The number of pathologically affected goats went down by a factor of 4.5, as compared to 1985. Mortality was reduced to one third. Abortions declined by a factor of 2.6 and infertility among goats by 1.6. The conclusion is that sheep of the Mongolian breed are not susceptible to infectious agalactia. Large-scale production tests of live cultures supported hopes for successful action on this infectious disease under Mongolian conditions.  相似文献   
995.
996.
A study was conducted to examine the adsorption and interaction mechanism of pirimicarb with smectites and soils. Studies were carried out in pesticide-smectite or soil-water systems and in pesticide-smectite-organic solvent systems, using homoionic samples of montmorillonite, smectites of different layer charge and soils with smectite in their clay fraction. The adsorption isotherms obtained at 30° and 45°C follow the empirical equation of Freundlich. In the adsorption of the pesticide by soils a highly significant correlation was seen between adsorption (distribution coefficient) and the content of smectite in them. In the studies in organic medium the formation of a smectite-pirimicarb bilayer complex with a basal d001 spacing of 18.55 Å was observed; the formation of this is also related to the nature of the interlayer cation and the layer charge of the smectite. According to the I.R. results, the interlayer cations of the silicate and the oxygen atom of the C–O group of the pesticide molecule are involved in the interaction mechanism.  相似文献   
997.
Teratogenic effects of methylparathion / Wofatox 50 EC/ and Parathion 20 WP as positive control material were tested in pheasant embryos. On the 12th day of incubation 0.1 ml of the emulsions or suspensions of the insecticides at different concentrations was inoculated into the air space of embryonated eggs. The following dose levels were employed: 27 and 270 mg/kg egg of Wofatox 50 EC, and 10 mg/kg of Parathion 20 WP. Morphological changes were evaluated by macroscopic, skeletal staining and light microscopic examinations of the embryos. Primary hypoplasia or atrophy developed in the cervical musculature /m. longus colli/ accompanied by lordosis and scoliosis of the cervical spine. In most cases we also found cyllosis .  相似文献   
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