A study was carried out to determine the possibility of a more-closed farming system for (Dutch) dairy farms. The objective of the study was to provide effective and economically profitable management advice for improving the animal-health status of farms. Management measures will only be successfully applied if supported by farmers and their advisors (such as veterinarians). Therefore, the perception of farmers and advisors of the importance of various risk factors for the introduction of diseases to a farm was determined by using bovine herpes virus type 1 (BHV1) as an example.
As part of the study, an evening-long workshop was organized and run thrice. In total, 49 farmers, veterinarians and AI technicians participated in these workshops. The computerized questionnaire technique was based on adaptive conjoint analysis (ACA). ACA has the advantage that participants can work with a large number of risk factors in a relatively short period of time. Another advantage of ACA (compared with standard questionnaires) is that the answers from each participant can be checked with regard to consistency with respect to the importance assigned to them. Data from participants with inconsistent responses can be excluded from further analyses. The results of the ACA interview were compared with the risk factors reported in the literature as being associated with BHV1 status (e.g. purchase of cattle, participation in cattle shows) and with farmers' actual management to prevent the introduction of diseases.
The workshop participants were all operating in the dairy sector and they seemed well aware of the risk of direct animal contacts for the introduction of BHV1. Farmers thought visitors to be more risky than did AI technicians and (especially) veterinarians. Farmers who purchased cattle or participated in cattle shows were of the opinion that the risks of direct animal contacts were more important than did farmers who were not involved in those practices. Farmers whose farms were BHV1-positive (and participated in cattle shows more often) thought the risk of participation smaller than did farmers with BHV1-negative farms. 相似文献
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
Seventeen cutaneous and oral tumours with light microscopic features of plasmacytomas from 16 dogs were studied. Clinically, most neoplasms were benign, although three recurred after excision and three were locally invasive. Tumours most often arose on the pinnae, digits, gingiva, and inguinal regions near areas of chronic inflammation and exhibited variable degrees of plasmacytic differentiation microscopically. Diagnosis of plasmacytoma was confirmed in paraffin-embedded tissues with a panel of leukocyte differentiation antigen markers that included cross-reactive antibodies for Mb-1 (CD79a), CD3, and vimentin and canine-specific antibodies for CD45RA and CD18. Immunoreactivity for Mb-1 and CD45RA, including staining of multinucleate cells and cells with karyomegaly, confirmed a B-cell origin of neoplasms, while staining for CD3 and CD18 revealed an extensive network of infiltrative T-cells and dendritic cells in tumours suggestive of a directed immune response. These findings (i) demonstrate the value of using a panel of antibodies for leukocyte antigens to differentiate plasmacytomas from other cutaneous and oral round cell tumours, and (ii) suggest that immune recognition and responsiveness within tumours may play a role in the behaviour of plasmacytomas in dogs by affecting tumour cell growth and differentiation. 相似文献
AbstractThe contribution of cell wall components and nonstructural carbohydrate (NSC) to grain filling in rice (Oryza sativaL.) was clarified by investigating the differences in the dynamics of hemicellulose, sugar composition of hemicellulose, β-(1→3),(1→4)-glucan, and NSC among cultivars with different grain filling capacities. This investigation was performed using the stems of standard, high yield and low harvest index (HI) cultivars. Hemicellulose concentration in stems tended to decrease slightly during the grain filling stage. This decrease was attributed to a decrease in β-(1→3),(1→4)-glucan concentration, which was detected as a decrease in glucose composition of hemicellulose in the stems during the grain filling stage. The rate of decrease and decrease in the amount of β-(1→3),(1→4)-glucan in the stems differed among the cultivars. These were higher in high yield and high HI cultivars than in relatively low yield and low HI cultivars. Moreover, a positive correlation was observed between the rate of decrease in β-(1→3),(1→4)-glucan and NSC, indicating similarities in the dynamics of β-(1→3),(1→4)-glucan and NSC among the cultivars. When the top half of panicle was removed, β-(1→3),(1→4)-glucan and NSC concentrations in the culm and leaf sheath did not decrease during the grain filling stage. Therefore, the β-(1→3),(1→4)-glucan in stems might be one of the sources that supply substrate to panicle as well as NSC.相似文献
AbstractTo elucidate the possible participation of hemicellulose decomposition in lodging resistance, we studied the change of hemicellulose and cellulose content in the stems of rice during the ripening stage by methylation analysis and the expression of related genes by Northern blotting. In the rice stem in ripening stage, content of (1-3,1-4)-β-glucan, a component of hemicellulose, decreased markedly although the content of arabinoxylan, a major component of hemicellulose, and cellulose showed little change during the same growth period. On the other hand, expression of the Gns 1 gene, which may encode (1-3,1-4) -β-glucanase that catalyzes the degradation of (1-3,14) -β-glucan, increased sharply in the stem. The mechanism of decomposition of (1-3,1-4) -β-glucan in rice stem and the possible association with lodging resistance is discussed. 相似文献