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81.
R. W. Paling C. Mpangala B. Luttikhuizen G. Sibomana 《Tropical animal health and production》1991,23(4):203-214
Summary Susceptible Ankole (Sanga:Bos indicus/Bos taurus) and crossbred Ankole x Jersey (B. taurus) and Ankole x Sahiwal (B. indicus) cattle derived from a farm in Rwanda with no recent history of theileriosis, were infected withTheileria parva stocks from Rwanda either by feeding infectedRhipicephalus appendiculatus ticks on the ears, inoculation of tick derived stabilate or natural exposure to tick challenge. The Ankole cattle originated
from local stock born and bred in East Coast fever (ECF) endemic areas of Rwanda. Disease, followed by spontaneous recovery,
was observed in 49 of the 72 Ankole cattle after infection withT. parva (68%); the other 23 animals (32%) died of ECF. In contrast 21 of the 33 infected crossbred cattle (64%) died of ECF. It is
concluded that the partialTheileria tolerance of the Ankole is, to a great extent, genetic. The basis of this partial tolerance seems to be their ability to
limit the explosive multiplication of macroschizonts during the acute phase of the disease.
Resumen Se infectó ganado Ankole susceptible (Sanga:Bos indicus/Bos taurus) y ganado cruzado Ankole x Jersey (Bos taurus) y Ankole x Sahiwal (Bos indicus) proveniente de una finca en Rwanda sin historia reciente de theileriosis, conTheileria parva procedente de Rwanda, mediante la adhesión en la oreja deRhipicephalus appendiculatus infectado, inoculación de estabilados derivados de garrapatas, o exposición natural a la enfermedad a través del vector. El ganado Ankole era originario de un área endémica de theileriosis en Rwanda. Se observó la enfermedad seguida de recuperación, en 49 de 72 animales Ankole infectados conT. parva (68%); los otros 23 animales murieron (32%). En contraste, 21 de los 33 animales cruzados infectados (64%), murieron. Se concluye, que la tolerancia parcial del ganado Ankole es de origen genético. Las bases de ésta tolerancia genética, parece debida a la habilidad para limitar en cierto modo la multiplicación explosiva de macroesquizontes, durante la fase aguda de la enfermedad.
Résumé On a infecté du bétail sensible, de race Ankolé (Sanga:Bos indicus/Bos taurus) et des croisés Ankolé x Jersey (B. taurus) et Ankolé x Sahiwal (B. indicus), provenant d'une ferme au Rwanda sans cas récents de theilériose, avec des souches deTheileria parva du Rwanda, par l'application de tiques (Rhipicephalus appendiculatus) infectées sur les oreilles, par inoculation de stabilat de tiques infectées ou par l'exposition à un challenge naturel de tiques. La souche d'Ankolé était originaire du cheptel local Rwandais, né et élevé dans les régions où la theilériose est endémique. La maladie suivie par la guérison spontanée fut observée dans 49 des 72 Ankolés (68%), les autres 23 animaux (32%) ont succombé à la theilériose. Par contre 21 des 33 croisées infectées (64%) ont succombé à la theilériose. Nous concluons que la tolérance partielle des Ankolés contre la theilériose, est génétique. La base de cette tolérance semble être leur capacité de limiter la multiplication explosive des macroschizonts pendant la phase aigu de la maladie.相似文献
82.
Advances in diagnostic ultrasonography 总被引:2,自引:0,他引:2
V B Reef 《Veterinary Clinics of North America: Equine Practice》1991,7(2):451-466
A wide variety of ultrasonographic equipment currently is available for use in equine practice, but no one machine is optimal for every type of imaging. Image quality is the most important factor in equipment selection once the needs of the practitioner are ascertained. The transducer frequencies available, transducer footprints, depth of field displayed, frame rate, gray scale, simultaneous electrocardiography, Doppler, and functions to modify the image are all important considerations. The ability to make measurements off of videocassette recorder playback and future upgradability should be evaluated. Linear array and sector technology are the backbone of equine ultrasonography today. Linear array technology is most useful for a high-volume broodmare practice, whereas sector technology is ideal for a more general equine practice. The curved or convex linear scanner has more applications than the standard linear array and is equipped with the linear array rectal probe, which provides the equine practitioner with a more versatile unit for equine ultrasonographic evaluations. The annular array and phased array systems have improved image quality, but each has its own limitations. The new sector scanners still provide the most versatile affordable equipment for equine general practice. 相似文献
83.
山羊脑灰质软化症 (POLIOEN CEPHALOMALACIA)和李氏杆菌病 (LIS TERIOSIS)是症状相似治疗方法截然不同的两种疾病。山羊饲养者和兽医工作者必须从两种疾病的细微差别中进行鉴别 ,以便正确治疗和处理病羊。多数情况下 ,这两种疾病出现在饲养条件比较好、但饲养方法不当的地方。特别是在快速育肥时。精饲料喂量过多 ,而含粗纤维的饲料喂量过少是诱发两种疾病的重要因素。突然更换饲料常常导致此病突然发作。脑灰质软化症 (通常又称为大脑皮层坏死症 )是缺乏硫胺 (即维生素B1)而造成的一种代谢性疾病。瘤胃环… 相似文献
84.
J Sherrill T Schock J L Dunn D J St Aubin V V Burnley S E Poet 《Journal of zoo and wildlife medicine》2001,32(1):17-24
Humoral immune responses of black-footed penguins (Spheniscus demersus) to DNA-mediated immunization with a beta-galactosidase reporter gene expression plasmid were evaluated. Six male and 6 female adult penguins received either test plasmid, pCMV-beta, containing the beta-galactosidase gene or control plasmid, pCI, lacking a gene for expression. Three birds from each group were used previously in a diluent control group and given one injection of sterile saline. All samples were screened for anti-beta-galactosidase antibodies by indirect enzyme-linked immunosorbent assay with anti-chicken immunoglobulin G as secondary antibody. Antibodies to beta-galactosidase were detected in the sera of pCMV-beta-inoculated penguins, with a peak response on day 21. Antibody titers of the test plasmid group versus both control groups on days 21, 28, and 42 differed significantly. These results demonstrate that black-footed penguins can be safely transfected with the gene encoding beta-galactosidase and will mount a humoral response against the in vivo-expressed protein. Knowledge from this initial study can be applied to the development of DNA-mediated vaccines against specific infectious diseases of penguins. 相似文献
85.
Scripture EW 《Science (New York, N.Y.)》1899,9(234):878-880
86.
Castle WA 《Science (New York, N.Y.)》1938,87(2267):531-534
87.
88.
89.
90.
Loehwing WF 《Science (New York, N.Y.)》1948,107(2786):529-533