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991.
In puppies weaning is a high risk period. Fecal changes are frequent and can be signs of infection by digestive pathogens (bacteria, viruses, parasites) and indicators of nutritional and environmental stress. The aim of this study was to define a pathological fecal score for weaning puppies, and to study the impact on that score of two intestinal viruses (canine parvovirus type 2 and canine coronavirus). For this, the quality of stools was evaluated on 154 puppies between 4 and 8weeks of age (100 from small breeds and 54 from large breeds). The scoring was performed immediately after a spontaneous defecation based on a 13-point scale (from 1; liquid to 13; dry and hard feces). Fecal samples were frozen for further viral analysis. Each puppy was weighed once a week during the study period. The fecal score regarded as pathological was the highest score associated with a significant reduction in average daily gain (ADG). Fecal samples were checked by semi-quantitative PCR or RT-PCR for canine parvovirus type 2 and canine coronavirus identification, respectively. The quality of feces was affected by both age and breed size. In small breeds, the ADG was significantly reduced under a fecal score of 6 and 7 for puppies at 4-5 and 6-8weeks of age, respectively. In large breeds, the ADG was significantly reduced under a fecal score of 5 whatever the age of the puppy. Whereas a high viral load of canine parvovirus type 2 significantly impacted feces quality, no effect was recorded for canine coronavirus. This study provides an objective threshold for evaluation of fecal quality in weaning puppies. It also emphasizes the importance to be given to age and breed size in that evaluation.  相似文献   
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Context   

Increased knowledge on diversity in wood properties would have implications both for fundamental research and for promoting a diversification of uses as material.  相似文献   
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An 11 yr old spayed female Labrador retriever was diagnosed with a right adrenal tumor. At surgery, adhesions to the right kidney were dissected, allowing the right kidney to be preserved. The tumor showed extensive invasion into the suprarenal vena cava. It was felt that thrombus removal via venotomy could not be performed. Instead, the vena cava was ligated caudal to the liver and cranial to the right renal vein. The neoplastic gland was then excised en bloc together with the portion of the invaded caudal vena cava. Hind limb edema had developed preoperatively and increased transiently in the first days postoperatively. The animal was discharged 6 days postoperatively with no other clinical disorders, and hind limb edema resolved over time. Histopathology identified a pheochromocytoma. The dog died 49 mo later. A neoplastic thrombus of the vena cava may require venotomy to allow thrombus removal. Occasionally, removal of the thrombus by venotomy may prove impossible. In such a situation, en bloc removal of the concerned portion of the vena cava may be performed with a good long-term outcome provided that gradual occlusion of the vena cava by the thrombus has allowed time for collateral circulation to develop.  相似文献   
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ABSTRACT: Foot-and-mouth disease virus (FMDV) is a highly infectious member of the Picornaviridae inducing an acute disease of cloven-hoofed species. Vaccine-induced immune protection correlates with the presence of high levels of neutralizing antibodies but also opsonising antibodies have been proposed as an important mechanism of the immune response contributing to virus clearance by macrophages and leading to the production of type-I interferon (IFN) by plasmacytoid dendritic cells (pDC). The present study demonstrates that the opsonising antibody titres mediating enhanced IFN-α responses in pDC were similar to neutralizing titres, when antigenically related viruses from the same serotype were employed. However, sera cross-reacted also with non-neutralized isolates of multiple serotypes, when tested in this assay. Both uncomplexed virus and immune complexed virus stimulated pDC via Toll-like receptor 7. An additional finding of potential importance for strain-specific differences in virulence and/or immunogenicity was that pDC activation by FMDV strongly differed between viral isolates. Altogether, our results indicate that opsonising antibodies can have a broader reactivity than neutralizing antibodies and may contribute to antiviral responses induced against antigenically distant viruses.  相似文献   
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The aim of our study was to detect the presence of Rickettsia spp. and Bartonella spp. in ticks and fleas collected from red foxes (Vulpes vulpes) in southeastern France during 2008. Using a genus-specific quantitative PCR (qPCR) assay, which was followed by a species-specific qPCR assay for the positive samples, 45.2% (33/73) of ticks (Rhipicephalus turanicus) were found to be infected with Rickettsia massiliae. 10.5% (2/19) of the fleas (Archaeopsylla erinacei) collected in the study tested positive for Rickettsia felis. A genus-specific qPCR assay did not reveal any Bartonella species in any of the ticks or fleas collected. The role of red foxes in the epidemiology of spotted fever caused by Rickettsiae species requires further investigation.  相似文献   
999.
Landscape dynamics increasingly challenge agronomists to explain how and why agricultural landscapes are designed and managed by farmers. Nevertheless, agronomy is rarely included in the wide range of disciplines involved in landscape research. In this paper, we describe how landscape agronomy can help explain the relationship between farming systems and agricultural landscape dynamics. For this, we propose a conceptual model of agricultural landscape dynamics that illustrates the specific contribution of agronomy to landscape research. This model describes the relationship between three elements: farming practices, landscape patterns and natural resources. It can stimulate agronomists to deal with research issues in agricultural landscape dynamics and enhance the interdisciplinary integration of farming systems in wider landscape research. On these premises, we discuss the main research issues that will benefit from an active involvement of agronomy, to understand, but also to assess landscape dynamics and to design relevant decision support systems.  相似文献   
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