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61.
A new disease of unknown bacterial aetiology has been observed in eucalyptus stands since 2009. It is characterized by die‐back, wilting and lesions on the branches, petiole and midrib in association with macroscopic and microscopic bacterial ooze. To date, this disease has been observed in stands of clonal Eucalyptus saligna, E. grandis and E. urophylla x E. grandis hybrids and in E. dunnii seedling plantations in the states of São Paulo, Rio Grande do Sul and Mato Grosso do Sul. Considering the economic importance of eucalyptus plantations and the potential losses caused by this disease, this study aimed to identify and characterize the causal agent. Thirty‐four strains were obtained from infected plants, which were collected in the field from four locations. The inoculation of detached leaves and intact rooted cuttings supported pathogenicity in eucalyptus. The phylogenetic analysis of four housekeeping genes (16S rDNA, gapA, recA and rpoB) as well as biochemical tests confirmed the identity of strains belonging to the species Erwinia psidii. This is the first report of E. psidii as the cause of wilt and die‐back in Eucalyptus spp. in Brazil.  相似文献   
62.

The present study attempted to verify the prevalence of and risk factors for diarrhea-causing agents in dairy calves from Brazil. Additionally, ages with a higher risk of occurrence for each agent were verified by means of the receiver operating characteristic (ROC) curve. The collections were performed on 39 farms, belonging to 29 municipalities located in eight states of Brazil. It was possible to conclude that the prevalence of Coronavirus, Rotavirus, Cryptosporidium spp., Eimeria spp., and nematodes was 7.20% (95% CI 4.54–9.78), 6.37% (95% CI 3.85–8.89), 51.52% (95% CI 45.26–55.57), 3.46% (95% CI 2.24–4.67), and 3.46% (95% CI 2.24–4.67), respectively. Ages with higher probabilities of occurrence of these diseases in calves were <?10, >?8, >?6, >?37, and >?36 days, respectively. Diarrhea occurred more significantly (P?<?0.0001) in animals less than 21 days old and mainly on those receiving milk through automatic feeders (P?<?0.001). Cryptosporidium spp. were a risk factor for the occurrence of Rotavirus, and vice versa (P?=?0.0039) and presented a positive correlation with Coronavirus (P?=?0.0089). Calves that drink water from rivers, streams, and ponds had a higher chance of being infected by Eimeria spp. (P?<?0.0001), as well as developing infection by nematodes (P?<?0.0001). The results found in this study highlight the importance of studying the agents of diarrhea together, once they act as coinfection where the losses triggered for the owners will involve some of these agents simultaneously.

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Gastrointestinal Lymphoma in 20 Dogs   总被引:1,自引:1,他引:0  
The records of 20 dogs with histopathologically diagnosed gastrointestinal (GI) lymphoma (LSA) evaluated between 1970 and 1984 were reviewed. Fifteen dogs were considered to have primary GI LSA, while five dogs had GI involvement in association with the multicentric form. Most clinical and laboratory findings were nonspecific, but positive-contrast upper GI radiography was suggestive of GI LSA in all of the dogs evaluated. Nine dogs had extensive lymphocytic-plasmacytic inflammatory infiltrates around the neoplastic foci, resulting in difficulty in obtaining a diagnosis of GI LSA when samples were obtained by endoscopy.  相似文献   
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Preleukemic syndrome in a dog   总被引:2,自引:0,他引:2  
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68.
The diagnosis of essential thrombocythemia in a cat was made by fulfilling the five applicable criteria set forth by the Polycythemia Vera Study Group for use in humans. The criteria were 1) a platelet count persistently above 600,000/microL, 2) a normal initial hematocrit that did not rise in response to iron therapy, 3) normal serum iron concentration, 4) absence of collagen fibrosis of the bone marrow, and 5) no cause for reactive thrombocytosis. In addition, normal thrombopoietin concentrations and splenic hypofunction were demonstrated. Melphalan was not effective in decreasing the platelet count and the cat died of sepsis.  相似文献   
69.
The cell surface glycoconjugates of blood lymphocytes from 19 dogs with and without neoplastic disease were quantitated using flow cytofluorometric analysis of the binding characteristics of 3 lectins, namely, wheat germ agglutinin, concanavalin-A, and Lens culinaris agglutinin. The specificity of lectin binding was determined using competitive monosaccharide inhibitors. The results show enhanced binding of concanavalin-A to blood lymphocytes from dogs with lymphosarcoma relative to healthy dogs, or those with a variety of neoplastic and nonneoplastic diseases.  相似文献   
70.
Cutaneous Hemangiosarcoma in 25 Dogs: A Retrospective Study   总被引:2,自引:1,他引:1  
Hemangiosarcomas confined to the skin and underlying muscle were surgically excised in 25 dogs. Tumors were staged based on their histological location (ie, dermal, hypodermal, and deep). Dermal (stage I) hemangiosarcomas were small, most commonly ventral-abdominal or preputial in location, and were associated with prolonged survival times (median survival, 780 days). Tumors with hypodermal (stage II) and underlying muscular involvement (stage III) were grouped together because of their larger size, bruise-like appearance, lack of anatomic predilection, biological behavior, and shorter survival times (median survival of 172 and 307 days for dogs with stages II and III, respectively). We conclude that dermal hemangiosarcomas may be effectively treated with surgery alone, whereas hemangiosarcomas located within the hypodermal tissues bear a poor prognosis and warrant wide surgical excision with adjuvant chemotherapy.  相似文献   
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