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891.
The purpose of this study was to determine the rate of decline and geographical distribution by municipality of clinical and subclinical African swine fever (ASF) in the affected areas of Spain. A second aim was to evaluate the performance of diagnostic tests in the Spanish ASF eradication program. Clinical outbreaks were confirmed using both the direct and indirect immunofluorescence test (and if both were negative, by the hemabsorption test). The serological status of swine was determined by an enzyme-linked immunosorbent assay (ELISA) and suspect serum samples were confirmed by the immunoblot assay.

The number of clinical outbreaks (herds) of ASF for 1989, 1990 and 1991 was 170, 347 and 207, respectively. The numbers of municipalities within each affected province experiencing acute outbreaks for the same time periods were 49, 69 and 48, respectively. Serologically diagnosed animals positive for ASF were 1.1% of animals tested in 1989, 0.5% in 1990 and 0.8% in 1991. The corresponding positive predictive values of the standard ELISA test used were 99.0, 97.9 and 98.8, respectively. Similarly, the number of municipalities within each affected province experiencing serologically positive subclinically infected animals was 269, 178 and 147 for each of the years 1989, 1990 and 1991, respectively.  相似文献   

892.
The objective of this study was to assess the effect of dietary copper and/or vitamin E supplementation on composition and oxidation of M. longissimus in Iberian pigs and to compare it with meat samples from pigs produced extensively and fed with acorn and grass. Grass had the highest α-tocopherol content (> 150 mg/kg DM), while acorns had the highest copper concentration (78.1 mg/kg DM). Dietary treatment did not affect copper composition in muscle and no interactions were detected between copper and α-tocopherol. The α-tocopherol content in muscle from pigs fed diets supplemented with α-tocopheryl acetate (100 mg/kg feed) was 1.5 times greater (p < 0.0001) than those from pigs receiving a basel diet. M. longisssimus dorsi from pigs fed extensively had a higher concentration of α-tocopherol than those fed in confinement with the basel level of α-tocopheryl acetate, but lower values than pigs fed supplemented levels. Total n -3 fatty acids (p < 0.02) and hematin (p < 0.0001) concentrations were significantly higher in muscle from pigs fed extensively than when fed in confinement. Muscle homogenates from Iberian pigs fed in extensive conditions showed significantly (p < 0.02) higher susceptibility to oxidation than those from pigs fed mixed diets. Dietary α-tocopheryl acetate supplementation (100 mg/kg feed) significantly (p < 0.05) reduced lipid oxidation of muscle, while dietary copper concentration did not modify susceptibility to lipid oxidation.  相似文献   
893.
894.
In a field trial conducted during 1992–93 and 1993–94, the effect of basal (B) nitrogen (N) (45 and 60 kg N ha−1) and foliar application (F) of water (W) or 10 kg N ha−1 and 400 or 600 ppm ethrel (E) (2-Chloro ethyl phosphonic acid) at 70 days after sowing was studied on leaf area index and dry mass at 90 days and pod number per plant, seeds per pod, 1000 seed weight, seed yield, oil content and oil vield at harvest of mustard ( Brassica juncea L. Czern & Coss.) cv. T-59. Recommended basal (B) application of 90 kg N ha (BN90) was used as control. On the basis of 2 year data it was found that basal application of 60 kg N and foliar spray of 10 kg N ha −1 and 600 ppm ethrel gave higher values for growth and yield characteristics and enhanced seed yield and oil yield by 12.5 and 14.8%, respectively over control BN90.  相似文献   
895.
896.
Selectivity of Amblygaster sirm by gill nets of seven mesh sizes ranging from 2.3 to 3.8 cm stretched mesh was studied for a period of 12 months in the coastal waters off Negombo on the west coast of Sri Lanka. The size range of fish caught was 9.0–22.0 cm. Selection by mesh sizes smaller than 3.0 cm was towards the lower end of the selection curve.

Estimated values for selection factors ranged from 5.11 to 6.03 and those for optimum selection lengths varied from 12.9 to 19.7 cm. The highest selection factor was observed for 2.9 cm mesh, probably due to wedging of larger individuals in this mesh.  相似文献   

897.
Inhalation therapy plays an increasing role in the management of equine respiratory disorders. Thisalternative to systematic treatment permits a high concentration of medication to act locally while minimizing side effects and residues. In human medicine, literature in this field is prolific and continuously renewed, whereas in veterinary medicine, applications of aerosol therapy are less extensive. This review considers the principles of action of the different types of devices used for inhalation, i.e., nebulization, metered-dose inhalation and dry powder inhalation, describes the technical and practical requirements for their use in the equine species and considers the advantages and disadvantages of each inhalation device. The pharmacological agents currently administered to horses by inhalation are also discussed. Perspectives of aerosol therapy in the equine species, including aerosols already used in human medicine and their potential applications for horses are described.  相似文献   
898.
Book review     
Poultry Health and Management: Chickens, Ducks, Turkeys, Geese, Quail, 3rd edn. By David Sainsbury, 1992. 214 pp., illustrated. Oxford, Blackwell Scientific Publications. £17.99. ISBN 0–632–03325–8.  相似文献   
899.
900.
Abstract— In a blinded trial to determine the efficacy of potentiated sulfa drugs in the treatment of canine pyoderma, 50 dogs with superficial pyoderma were randomly assigned to receive either once or twice daily trimethoprim-sulfadiazine (30mg.kg-1) or once daily sulfadimethoxine-ormetoprim (55mg.kg-1 on the first day, then 27.5 mg.kg-1 thereafter). Dogs were evaluated prior to antibiotic therapy. Clinical efficacy of the antibiotic was assessed after 3 weeks of antibiotic therapy and, if needed, after 6 weeks of antibiotic therapy. Forty-five dogs completed the study; 43 dogs were used in the statistical analysis. The percentage of dogs that were cured of their pyoderma with once daily trimethoprim-sulfadiazine was 38.5% by 3 weeks and 75.9% by 6 weeks. With twice daily trimethoprim-sulfadiazine, 57.1 and 78.6% of dogs were cured by 3 and 6 weeks, respectively. With once daily sulfadimethoxine-ormetoprim, 75.0 and 100% of dogs were cured by 3 and 6 weeks, respectively. This difference was not statistically significant, possibly due to the low sample size. Few adverse effects were noted. Résumé— Dans une étude en double aveugle pour apprécier l'efficacité des sulfamides potentialisés dans le traitement des pyodermites canines, cinquante chiens présentant une pyodermite superficielle ont reçu, au hasard, soit deux fois ou une fois par jour du triméthoprime-sulfadiazine (30 mg.kg-1) ou une fois par jour du sulfadiméthoxine-ormétoprime (55mg.kg-1 le premier jour, puis 27.5 mg.kg-1). Les chiens ont étéévalués avant le traitement. L'efficacité clinique de l'antibiotique a été appréciée après 3 semaines de traitement et, si besion est, après 6 semaines. Le pourcentage de chiens guéris avec une prise quotidienne de triméthoprime-sulfadiazine était de 33.5%à 3 semaines et 75.9%à 6 semaines. Avec des prises biquotidiennes de triméthoprime-sulfadiazine 57.1% et 78.6% des chiens étaint guéris à 3 et 6 semaines. Avec une prise quotidienne de sulfadiméthoxine-ormétoprime, 75.0% et 100.0% des chiens étaient guéris à 3 et 6 semaines. Cette différence n'était pais statistiquement significative, probablement à cause de la taille trop faible de l'échantilon. Très peu d'effects secondaires ont été notés. Zusammenfassung— Für eine Blindstudie zur Bestimmung der Wirksamkeit von potenzierten Sulfonamidpräparaten bei der Behandlung kaniner Pyrodermie wurden 50 Hunde mit oberflächlicher Pyodermie zufällig ausgewählt, um entweder einmal oder zweimal täglich Trimethoprim-Sulfadiazin (30mg/kg) oder einmal täglich Sulfadimethoxin-Ormetoprim zu erhalten (55 mg/kg am ersten Tag, danach 27,5 mg/kg). Die Hunde wurden vor der antibotischen Therapie untersucht. Die klinische Wirksamkeit der Antibiose wurde nach 3 Wochen antibiotischer Therapie und, wenn nötig, nach 6 Wochen antibiotischer Therapie ausgewertet. 45 Hunde durchliefen die Studie vollständig; 43 Hunde fanden in die statistische Analyse Eingang. Der Prozentsatz der Hunde, deren Pyrodermie durch einmal tägliches Trimethoprim-Sulfadiazin geheilt wurde, lag bei 38,5% nach 3 Wochen und bei 75,9% nach 6 Wochen. Bei zweimaliger Trimethoprim-Sulfadiazin-Verabreichung wurden 57,1% und 78,6% der Hunde nach 3 bzw. 6 Wochen geheilt. Mit einer einmal täglichen Verabreichung von. Sulfadimethoxin-Ormetoprim wurden 75,0% und 100% der Hunde nach 3 bzw. 6 Wochen geheilt. Dieser Unterschied war statistisch nicht signifikant, möglicherweise aufgrund der geringen Fallzahlen. Es wurden nur wenige Nebenwirkungen festgestellt. Resumen A cincuenta perros que presentaban pioderma superficial se les evaluó para la eficacia de antibioticos potenciados de tipo sulfamídico en el tratamiento del pioderma canino, por medio de la administración de una a dos veces diarias de trimetoprim-sulfadiazina (30 mg/kg), o sulfadimetoxinaormetoprim una vez al día (55 mg/kg en al primer día, y 27.5 mg/kg después de la primera dosis). Los animales se examinaron antes del tratamiento con antibióticos. La eficacia clínica del tratamiento se evaluó a las tres o seis semanas en los casos necesarios. Cuarenta y cinco de los perros completaron el estudio; 43 se utilizaron en analisis estadísticos. El porcentaje de perros curados con el tratamiento diario a base de trimetoprim-sulfadiazina fué del 38.5% a las 3 semanas, y 75.9% a las 6 semanas. De los animales tratados dos veces al día con trimetoprim-sulfadiazina, el porcentaje de cura fue del 57.1% y 78.6%, a las 3 y 6 semanas respectivamente. Con el tratamiento a base de sulfadimetoxina-ormetoprim una vez al día, 75.0% y 100% de los perros fueron curados a las tres y seis semanas. La diferencia no se encontró estadísticamente significativa, posiblemente debido al reducido número de perros evaluados. Se observaron posas reacciones adversas a la medicación.  相似文献   
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