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891.
O el Sawi Mohamed M H Tag el Din S M el Sanousi 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1989,42(2):169-172
Clostridium chauvoei CH3 and Kad1 strains were found to cause marked changes in the blood parameters during the course of blackleg disease. These changes displayed by CH3 were found to be more marked than the local Kad1 strain. Results of changes in the haematological values in calves infected with blackleg organisms, showed an increase in RBC, PCV, Hb and the total leukocyte count. MCHC and MCH remained within normal range values, however, a terminal significant increase of MCV was obtained. Thrombocytes showed a steady drop after infection to the time of death of the animals. 相似文献
892.
893.
本文详细报道了西瓜蔓枯病的症状和病原菌的形态特点,并鉴定其有性阶段为Mycosphaerellamelonis(Pass)Chiu et Walker,无性阶段为Ascochyta-cucumis Fautr et Roum.此外,还在其他瓜类作物上作了病原菌的致病性试验. 相似文献
894.
Immunogenicity of Brucella abortus salt-extractable proteins 总被引:5,自引:0,他引:5
The immunogenic properties of salt-extractable proteins and chromatographic fractions thereof from Brucella abortus were evaluated in lemmings (Dicrostonyx rubricatus). The efficacy of the Brucella proteins as immunogens was determined after challenge with virulent B. abortus strain 2308 and was based on protection against clinical signs and gross lesions of brucellosis, as well as on numbers of viable Brucella in the spleen. Vaccination of lemmings with as little as 0.1 microgram of salt-extractable proteins (CSP) suppressed splenic infection, resulting in reduced numbers of viable organisms per spleen of 5-6 logs compared to non-vaccinated controls. Protein fractions separated by column chromatography were generally effective in reducing splenic infection, and contained proteins with molecular weights of 30,000, 20,000 and 12,000. Vaccines containing chemically modified dodecanoyl-CSP offered no additional advantage over unmodified CSP vaccines. 相似文献
895.
Chicken anemia agent in the United States: isolation of the virus and detection of antibody in broiler breeder flocks 总被引:4,自引:0,他引:4
Chicken anemia agent (CAA) was isolated from broiler chickens in Texas with a blue wing or anemia dermatitis-like syndrome. Specific-pathogen-free chicks inoculated with field material developed anemia, and CAA was isolated in MDCC-MSB1 cells from bone marrow and lymphoid tissue from inoculated chicks. One isolate, designated EF88/78/276, was further characterized. Infectivity of EF88/78/276 was resistant to treatment with chloroform and with heat at 70 C for 5 minutes. EF88/78/276 was indistinguishable from the Cux-1 and Gifu-1 isolates of CAA by cross-neutralization tests. Almost all 1-day-old susceptible chicks inoculated intramuscularly with EF88/78/276 developed anemia, but contact-infected chicks did not. Antibody to CAA was detected in broiler breeder flocks from Texas, the Delmarva peninsula, and Alabama. 相似文献
896.
Armillaria species in northern Britain 总被引:1,自引:0,他引:1
S. C. GREGORY 《Plant pathology》1989,38(1):93-97
Five species of Armillaria, A. borealis, A. cepistipes, A. ostoyae. A. mellea and A. lutea , were identified among 145 isolates collected from sites in northern Britain. Most of the collection sites were in coniferous woodland containing dead or dying trees and A. ostoyae , a well-known pathogen of conifers, was the most frequently isolated species. Two species believed to be weakly pathogenic, A cepistipes and A. lutea , were also commonly found; the former has only rarely been recorded in Britain before. The significance of the records is discussed. 相似文献
897.
垃圾浸出液厌氧处理研究 总被引:8,自引:0,他引:8
本研究采用厌氧—好氧生物氧化的工艺技术,自行设计和制造了一套有机玻璃为材料的模拟装置,对垃圾浸出液进行处理研究。经试验结果表明,利用本设计装置处理后的污水,可运到国家农田灌溉的污水排放指标并基本达到国家三类废水的排放指标。该成果已通过市级专家鉴定,并将应用于垃圾场淤出污水的处理工程。 相似文献
898.
Fatal poxvirus infection in association with FIV infection 总被引:1,自引:0,他引:1
899.
A B Gardner C E Gardner 《Veterinary Clinics of North America: Food Animal Practice》1989,5(3):653-664
Dairy practice often requires substantial time commitments. Those veterinarians with families may find that if they do not actively budget some time for spouse and children, the family unit may suffer. A successful practice and meaningful family life are both possible if the doctor or doctors involved are willing to work for their achievement. 相似文献
900.
G S Smith K K Rozman D M Hallford D L Rankins M F Khan 《Journal of animal science》1989,67(1):187-195
Recently we reported elimination of radioactivity from [14C]heptachlor from body stores of lactating ovines, mainly into excreta rather than milk, contrasting sharply with bovines. To further assess heptachlor metabolism and clearance by ovines, 12 fine-wool wether lambs (41 +/- 3 kg) housed in metabolism stalls were fed pelleted alfalfa hay (96%) plus molasses (3%) ad libitum and were dosed i.p. once with [14C]heptachlor (1.643 mg/kg body wt; sp. act. = .89 microCi/mg). Feces and urine were collected separately and quantitatively. Light mineral oil was mixed with feed (5 g/100 g) of six lambs and trans-stilbene oxide, an inducer of biotransformational enzymes, was administered i.p. (4 g/hd initially; 2 g/hd daily thereafter) through 20 d to three lambs given each mineral oil treatment, in 2 x 2 factorial arrangement. Feces, urine, blood, bile and body tissues were assayed for total 14C activity. Radioactivity (heptachlor and [or] metabolites) eliminated into excreta during 21 d amounted to 34 to 36% of dose administered, of which 67% appeared in urine and 33% in feces. Biological half-time for elimination into excreta was 11.3 d [Kel = -.061/d], similar to 11.7 d we reported for lactating ewes. Clearance from blood had T1/2 = 14 d. Neither mineral oil nor trans-stilbene oxide altered rate or route of 14C activity excreted or concentrations of 14C activity in blood. Results confirmed that ovines eliminate heptachlor much more rapidly than bovines. 相似文献