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61.
A. J. Wilson J. Paris A. G. Luckins F. K. Dar A. R. Gray 《Tropical animal health and production》1976,8(1):1-11
Summary Three groups of Boran cattle were maintained under different trypanocidal drug regimes for 29 months in an area of “medium”
tsetse challenge. The development of immunity to trypanosomiasis in the cattle was assessed on the basis of changes in trypanocidal
drug requirement, development of parasitaemia, ability to maintain normal blood values, growth and response to challenge after
the withdrawal of the drugs. Observations were also made on serum antibody content by immunofluorescence and on serum immunoglobulin
levels.
Cattle treated with Berenil on the development of clinical disease developed a partial immunity to trypanosomiasis after two
years. Cattle treated as a group with Berenil on the development of patent parasitaemia in any one animal of the group did
not develop immunity. Cattle treated as a group with Samorin using the same criterion for treatment developed a degree of
immunity to the disease.
It was concluded that group treatment with Samorin was the most suitable of the three regimes examined for the maintenance
of beef cattle in a tsetse infested area.
Resumen Se mantuvieron tres grupos de ganado Boran durante 29 meses bajo differentes regímenes terapéuticos en un área donde la concentración de moscas tsetse era mediana. Se llevó a cabo la evaluación del desarrollo de la inmunidad contra la tripanosomiasis teniendo como base los diferentes cambios en el requerimiento de drogas, desarrollo de parasitemia, abilidad para mantener los valores sanguíneos normales, crecimiento y respuestas a la descarga de parásitos después del retiro de la terápia. Se hicieron también observaciones del nivel de anticuerpos séricos por inmunofluorescencia y se determinó el nivel de inmunoglobulinas. Los animales tratados con Berenil cuando mostraban signos clínicos de la enfermedad, desarrollaron una inmunidad parcial a la tripanosomiasis después de dos a?os. Los animales tratados en grupo con Berenil cuando se detectó parasitemia en cualquier animal del grupo no desarrollaron inmunidad. El ganado tratado con Samorin en base de grupo siguiendo el mismo criterio para el tratamiento, desarrolló cierto grado de resistencia a la enfermedad. Se concluye que el tratamiento de grupo utilizando Samorin fue el mejor de los tres regímenes estudiados para el mantenimiento de ganado de carne en un área infestada de moscas tstse.
Résumé Trois groupes de bovins Boran ont été maintenus vingt neuf mois, sous différents traitements trypanocides, dans une zone “moyennement” infestée de tsé-tsé. Le développement de l'immunité à la trypanosomiase a été évalué à partir des changements dans les besoins en trypanocides, du développement de la parasitémie, de l'aptitude à maintenir les valuers normales du sang, de la croissance et de la réaction à l'infection après la suppression des médicaments. Des observations ont aussi été faites sur la présence d'anticorps sériques par immunofluorescence et sur les teneurs en immunoglobines sériques. Le bétail traité au Berenil à l'apparition de signes cliniques a été partiellement immunisé au bout de deux ans. Dans le groupe du bétail traité au Berenil à l'apparition d'une parasitémie évidente, aucun animal n'a présenté d'immunité. Le groupe de bovins traité au Samorin, selon les nêmes critères a été bien immunisé.相似文献
62.
The epidemiology of tick-transmitted disease cannot be understood until those factors considered important to the life-cycle of the tick are properly investigated. Existing experimental results on the development of different stages of the tick life-cycle have been examined with a view to obtaining biological development rates for the purpose of predicting development under field conditions where temperature fluctuates. Field studies carried out in Ireland have enabled the predicted development times to be compared with those observed for several stages of the tick life-cycle. It is hoped that the models presented will clarify the importance or otherwise of climate to tick development and explore the potential of formulating a successful prediction system for tick activity. Ultimately such a system should aid control of tick-transmitted diseases. 相似文献
63.
Radicle emergence in lettuce seeds cultivar ‘Hilde’ was reduced by NH4NO3 above 8×10?2M, while radicle extension was inhibited by 8×10?2M NH4NO3 and no seedlings emerged. Inhibition of radicle emergence by 8 and 16×10?2M NH4NO3 was prevented by soaking seeds for 4 h before sowing in a mixture of and kinetin+phosphate buffer, and was partially prevented by soaking them for 4 h before sowing in phosphate buffer. These treatments did not prevent inhibition of radicle emergence by 32×10?2M NH4NO3, but seeds soaked in growth regulators or phosphate buffer before sowing and taken from this NH4NO3 solution after 7 days and washed to remove excess salt gave 45–52% germination compared with 12 % for untreated seeds. Pre-treatment of the seeds did not prevent the inhibitory effect of NH4NO3 on radicle extension. In field experiments seeds treated with growth regulators + phosphate buffer or phosphate buffer alone gave a higher final percentage emergence from soils given 125 kg N/ha than did untreated seeds. 相似文献
64.
65.
The effect of fluid (5% dextrose in water or lactated Ringer's solution) administered intravenously on the development of seizures after cervical myelography with metrizamide was studied in 10 dogs. In a crossover experimental design, 8 dogs were used twice. Urine output was measured during the second part of the study to determine whether diuresis was a factor affecting seizure development. Dogs given 5% dextrose in water had significantly (P less than 0.05) fewer seizures than did dogs given lactated Ringer's solution. This was attributed to an increase in CSF glucose concentration and was not associated with diuresis. 相似文献
66.
D E Gray 《The Veterinary record》1976,98(14):271-274
Veterinary science is well supplied with abstracting and indexing hournals. Both experience and an investigation undertaken for the Food and Agriculture Organisation indicate that they are comprehensive in scope and subject coverage. Computer operation of information services is now routine, and mechanised alerting and retrospective services are available. A veterinary round table was set up in 1973 by the Commission of the European Communities to attempt to improve veterinary information. The round table is conducting a detailed study of the value of the available machine information systems to veterinarians and is compiling a multi-lingual thesaurus. In addition, it is investigating the need for a new review journal, methods of recording animal disease incidence and variations in the needs of the different types of veterinarians for information. The use of machine information systems is expected to become more widespread in the near future. Many will be available on-line, a method of working which offers great advantages in speed and flexibility of operation. 相似文献
67.
Gray MJ 《The Journal of small animal practice》2005,46(10):499-503
A mature, neutered male domestic cat was presented with a chronic axillary wound of unknown origin and at least three years' duration. The diagnostic investigation included screening tests for feline leukaemia virus and feline immunodeficiency virus, tissue culture and histological examination. No underlying aetiology or perpetuating cause could be identified. An omental flap was created, passed via a subcutaneous tunnel, and packed into the wound site after excision of all chronic granulation tissue. The skin defect was closed using an omocervical axial pattern skin flap. A small area of the distal edge of the flap became necrotic but the defect healed by second intention. To the author's knowledge, this is the first clinical report of the use of an omocervical skin flap for repair of a chronic axillary wound in a cat. This flap offers a useful alternative where the use of a thoracodorsal axial pattern flap is not possible due to the extent of the lesion. 相似文献
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