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81.
The ultrasonographic appearance and size of the liver and kidneys of a litter of five pups was examined from birth until six months of age, and compared with a group of five adults of the same breed. Increased renal cortical echogenicity was evident for the first two weeks of life. Up to 12 weeks of age renal size was relatively large in comparison with body size parameters. After 12 weeks measures of renal size were proportionate with body size and were not significantly different from adult dogs. The neonatal liver had a similar ultrasonographic appearance to the adult, although in the first eight weeks parenchymal echogenic stippling was less coarse and portal veins were less well delineated. Measures of hepatic length were inaccurate during the first four weeks after birth due to changes in body conformation. From eight weeks to six months of age these measures were proportionate with body size, although the ratios differed from adult dogs. 相似文献
82.
83.
J S Gray 《Research in veterinary science》1983,35(3):318-324
It was found that surprisingly low doses of four babesicides were effective against Babesia divergens in gerbils and it was concluded that this was due to the involvement of host resistance, which may be of a non-specific nature. The efficacy of the drugs relative to each other was the same in gerbils as in cattle and this host-parasite system is evidently more suitable for the screening of babesicides than are other rodent babesia systems. The prophylactic dose of imidocarb dipropionate required to provide a similar degree of protection in gerbils as in cattle was found to be much higher and was very close to toxic levels. Challenge infections resulted in sterile immunity. Acute babesiosis in gerbils could be cured with all four drugs if parasitaemias were below approximately 45 per cent and packed cell volumes above 18 per cent at treatment. 相似文献
84.
B G Brown E R Kogelschatz B W Gray P D Garrett V K Ganjam 《American journal of veterinary research》1984,45(11):2389-2392
A surgical technique was devised to collect rete testis fluid from 14 mature goats. The tubular portion of the extratesticular rete testis was cannulated where it penetrated the tunica albuginea of the testis under the center of the head of the epididymis. The tip of the cannula was sutured in place in the extratesticular rete testis and the opposite end was passed through the scrotum and into a plastic collection bottle. The bottle was glued to pillow ticking, which was sutured to the scrotum. Continuous flow of rete testis fluid occurred for 0 to 14 days and was usually terminated by a sperm clot in the cannula. The flow rate was 0.59 +/- 0.37 ml/hr. 相似文献
85.
A reovirus-like agent was identified from an outbreak of enteritis in young lambs. From its morphology and immunological relationship with calf rotavirus, it was concluded that it was a rotavirus which infects lambs. 相似文献
86.
The clinical signs and pathological features of back muscle necrosis (BMN) in four pigs from three English pig herds were similar to those recorded in pigs from mainland Europe. The observations made support the view that BMN is a special manifestation of the porcine stress syndrome. Diagnosis of acute BMN can be made clinically supported by the analysis of plasma creatine phosphokinase activity and can be confirmed post mortem by macroscopic and microscopic observation on the back muscles. 相似文献
87.
Over the four-year period 1975-78 attempts were made to identify virus in samples from 1231 outbreaks of disease in cattle, and 682 outbreaks of disease in sheep. A virus identification was possible in 26 per cent of these disease outbreaks. The nature and significance of these virus infections is discussed. 相似文献
88.
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
89.
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
90.
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