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941.
A 7-year-old male Kerry Blue Terrier had been compensating for a visual deficit for approximately 2 months. Five days before examination, the dog had suddenly lost all vision and the pupils had become widely dilated and unresponsive to light. Ophthalmic examination revealed inflammation of the optic discs. Response to therapy was favourable but temporary.
Post mortem findings consisted of granulomatous optic neuritis, meningoencephalitis and chorioretinitis, similar to reticulosis.  相似文献   
942.
Sera were produced in rabbits against nine Moraxella bovis strains isolated in Brazil and three in the United States. Antigens were prepared for double immunodiffusion tests by thawing concentrated suspensions of the strains. Sera were tested against homologous and heterologous antigen preparations by the double immunodiffusion method. Sera showing precipitin bands with heterologous antigens were absorbed. Antigenic differences were detected between the strains and a provisional grouping of strains of M. bovis was suggested on the basis of antigenic composition. Differences between isolates from different geographical locations were found and some strains appeared antigenically more complex than others. The relevance of this work to vaccine production was suggested.  相似文献   
943.
The incidence and direct financial loss caused by babesiosis were evaluated in 121 Holstein Friesian female cattle that formed eight cohorts (1981–1988) of a dairy farm located approximately 24° 55′S 65° 29′W in Salta, Argentina. Female calves born in 1986 and 1987 (n=32) were vaccinated with a live Babesia vaccine at six months of age.

No cases of babesiosis occurred in the vaccinated cattle. The incidence of babesiosis in the six non-vaccinated cohorts was 23.6% (21/89). Eighteen of the cases were the result of Babesia bovis, one to Babesia bigemina and two to a mixed infection. Two cattle died of B. bovis infection in spite of drug treatment (diaminazene, 3.5 mg kg−1). No disease occurred in cattle younger than seven months or older than 24 months. The number of cases according to age of cattle was: 7–9 months, 5; 10–12 months, 6; 13–24 months, 10.

Financial loss for the six cohorts that suffered clinical cases amounted to US $ 1624.6 (prices in October 1990)—62% were the result of physical losses and 38% to costs of control. A benefit-cost analysis of vaccination was carried out assuming that 95% of the mortality and morbidity losses of the six non-vaccinated cohorts was prevented after a single inculation of a live vaccine (cost of a dose plus administration was US $ 4.2. The benefit-cost ratio was 4:1 for each US dollar expended.  相似文献   

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Twenty-nine new records are reported from Turkey. The fungi species, including their macro-and microscopic features and distributions, are described. http://www.phytoparasitica.org posting July 14, 2004.  相似文献   
948.
Eggs and L1 nymphs of the greenhouse whiteflyTrialeurodes vaporariorum (Westwood) (Hem.: Aleyrodidae) on bean leaves were directly sprayed with the fungicides maneb and mancozeb at recommended rates for practical use. Strong ovicidal and nymphicidal effects were observed. These fungicides may prove to have practical use for integration in IPM programs for whitefly control, as they also exert low or no toxicity to the whitefly parasitoidEncarsia formosa. http://www.phytoparasitica.org posting April, 30, 2004.  相似文献   
949.
During a nematode survey, severe infections of tobacco feeder roots and heavy soil infestations byMeloidogyne incognita race 1 were found in S. Miguel (Azores islands, Portugal). This is the first record ofM. incognita infection of tobacco in Azores. Morphology of various life stages, analysis of the esterase electrophoretic pattern and differential host tests were used for nematode characterization and identification. Nematode-induced mature galls were spherical and/or ellipsoidal and usually contained more than one female, males and egg masses with eggs. Feeding sites were characterized by the development of giant cells that contained granular cytoplasm and many hypertrophied nuclei. Giant cell cytoplasm was aggregated along a thickened cell wall. Vascular tissues within galls appeared disorganized. The relationship between the initial nematode population density and growth of tobacco plants was tested in a glasshouse experiment in which inoculum levels varied from 0 to 512 eggs and juveniles (J2) cm−3 of soil. Seinhorst’s model was fitted to height and top fresh weight data of the inoculated and control plants. Tolerance limits with respect to plant height and fresh top weight of tobacco cv. ‘Erzegovina’ plants toM. incognita race 1 were estimated as 1.25 eggs and J2 cm−3 of soil. The maximum nematode reproduction rate was 404.7 at an initial population density of 4 eggs and J2 cm−3 of soil. http://www.phytoparasitica.org posting March 2, 2004.  相似文献   
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