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141.
M. Nagai M. Sato H. Nagano H. Pang X. Kong T. Murakami T. Ozawa H. Akashi 《Veterinary microbiology》1998,60(2-4):271-276
Cytopathogenic and non-cytopathogenic bovine viral diarrhea viruses (BVDVs) were isolated from cattle with mucosal disease or persistent infection in Japan. These isolates were compared for antigenic properties by cross-neutralization tests with Japanese reference strains of BVDV belonging to classical type 1. Significantly low cross-reactivity to reference strains was noted, indicating the viruses to possibly represent a new serotype in Japan. Thus, to determine the genotype of the isolates, nucleotide sequences of the 5′ untranslated region were determined and compared with those of previously reported BVDV 1 and 2. The isolates were clearly shown to belong to BVDV 2, not to BVDV 1. 相似文献
142.
Michael J. Murray Fabio del Piero Stuart C. Jeffrey Michael S. Davis Martin O. Furr Edward J. Dubovi John A. Mayo 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1998,12(1):36-41
Of 17 foals born on a Thoroughbred breeding farm between March and April 1995, infection with equine herpesvirus type 1 (EHV-1) was associated with neonatal morbidity in 5 foals, 3 of which died or were euthanized. Morbidity and mortality were associated with pulmonary inflammation, and EHV-1 was identified in the lungs of the 3 foals that died. All neonatal EHV-1 infections occurred in foals of mares housed in the same pasture and barn. No other clinical manifestations of EHV-1 infection (eg, abortion, neurologic disease, or respiratory disease) occurred during this outbreak. Three foals were treated with acyclovir (1 died, 2 survived), which may have influenced the clinical outcome in the surviving foals. 相似文献
143.
J. A. LEIGH 《Veterinary journal (London, England : 1997)》1999,157(3):225-238
The prevalence of bovine mastitis has been reduced over the past 25 years due to the implementation of a five-point control plan aimed at reducing exposure, duration and transmission of intramammary infections by bacteria. This has markedly reduced the incidence of bovine mastitis caused by bacteria which show a contagious route of transmission, but has had little effect on the incidence of mastitis due to bacteria which infect the gland from an environmental reservoir. Streptococcus uberis is one such bacterium which is responsible for a significant proportion of clinical mastitis worldwide.The inadequacies of the current methods of mastitis control have led to the search for additional measures, particularly vaccines to prevent intramammary infection by this bacterium. Such an approach requires detailed knowledge of the pathogenesis of intramammary infection. Our understanding of this area has grown in recent years but a lack of information still hampers disease control. Both live vaccines and, recently, crude sub-unit vaccines have shown promise against bovine mastitis due to S. uberis. Vaccines against mastitis must, however, be able to control infection without the participation of a marked inflammatory response. This review provides an overview of the recent advances which have been made in our understanding of host-pathogen interactions which promote infection and disease and highlights areas for strategic research aimed at controlling this bacterial infection. 相似文献
144.
SUMMARY: Experimental infection of Tetrahymena pyriformis was conducted on ornamental fishes with skin wounded by acetic acid treatment. Among fishes used in this experimental infection, guppy Poecilia reticulata , pristella Pristella maxillaris , neontetra Paracheirodon innesi and cherry barbs Puntius titteya proved to be sensitive to challenge, while medaka Oryzias latipes , dwarf gourami Colisa lalia , goldfish Carassius auratus , platy Xiphophorus maculatus and angelfish Pterophyllum scalare were resistant. In catfish Corydoras aeneus infection was unsuccessful. Exposure to Tetrahymena at ≥100 cells/mL at 25 to 30°C and at pH of 6.0 to 8.0 resulted in the successful infection of some sensitive fish species. Histological and bacteriological observations suggest that deeply destroyed skin tissues from the acid-treated method are the primary factors in successful infection. 相似文献
145.
2009年1月11日,北方森林动物园发生一起自繁自养的亚成体东北虎感染巴氏杆菌死亡病例。本病例从发病到死亡共5 d时间,病程较短,以食欲下降至废绝,饮水量不变,精神沉郁,口腔腺体分泌增多、流涎,呈滴水样,腹部疼痛感明显为特征,口服诺氟沙星和多酶片治疗无效后改用肌注头孢哌酮钠和庆大霉素治疗,3 d后出现神经症状抽搐死亡。剖检肝脏表面有大量的针尖大小黄白色点状坏死灶。根据临床症状、病理剖检和实验室检查,确诊为巴氏杆菌感染。 相似文献
146.
147.
G H Sorensen 《Acta veterinaria Scandinavica》1974,15(4):544-554
The study comprises 136 strains of Corynebacterium pyogenes originating from cattle (105), swine (20), sheep (1), and insects (10). For comparison 2 strains of human origin and 1 strain of Gorynebacterium hemolyticum were examined.One of the bovine strains was atypical, being gelatinase-negative, otherwise the strains of Cb. pyogenes were found to be biochemically identical apart from minor deviations in fermentation patterns (Table 1). Neither were antigenic differences demonstrated (gel diffusion analyses, Figs. 1 and 2).Both of the human strains agreed biochemically with Cb. pyogenes (Table 1). By gel diffusion cross analyses one of them was found to be identical with Cb. pyogenes, the other not, though anti-genically related to it (Fig. 2).Gb. hemolyticum deviated biochemically as well as serologically from Gb. pyogenes, but the 2 organisms shared antigenic determinants (Fig. 3). 相似文献
148.
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150.
中蜂来源的微孢子虫对意蜂工蜂的侵染性研究 总被引:2,自引:0,他引:2
为探讨中蜂来源的微孢子虫对意蜂的侵染性,本试验将纯化自中蜂的微孢子虫,以每只蜂1×105个和5×105个孢子的接种量,分别给2日、5日、8日、11日龄无微孢子虫感染的意蜂成年工蜂接种,在30℃±0.5℃,65%~80%RH,黑暗中隔离饲养10日后,各日龄工蜂的平均感染率达86.3%~100%,每只蜂中肠的平均产孢量为5.60×105~3.39×106个。在两接种量下,2日、5日龄意蜂工蜂的产孢量均显著(P<0.05)高于8日、11日龄的产孢量。试验首次证实了中蜂来源的微孢子虫对意蜂成年工蜂具较强的侵染性。 相似文献