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排序方式: 共有573条查询结果,搜索用时 15 毫秒
1.
The activity of diflubenzuron against eggs ofLobesia botrana Den. & Schiff. was assayed with a dipping procedure, at 22° and 27° C. The compound was much more active at 27°C (LC-50 = 0.0072%) than at 22°C (LC-50 = 0.195%). 相似文献
2.
Wild waterfowl is considered a natural reservoir of potentially infectious agents and a source of pathogenic viruses like avian paramyxoviruses type 1 (APMV 1). In 1997, commercial poultry in Argentina had reached the status of being free from virulent Newcastle disease virus (NDV) infections. Vaccination and biosecurity measures are actively performed to maintain this preferential sanitary condition. However, the risk of reintroduction of pathogenic viruses is always present. In this context, we conducted a study to describe the status of wild healthy birds in a geographic region relevant for the poultry industry. The presence of anti-NDV antibodies was determined in different species in all areas sampled suggesting previous contact with NDV. Seven ND viruses were isolated and characterized as apathogenic strains by biological and molecular methods. The phylogenetic analysis revealed that the majority of the Argentinian isolates form a subgroup related to viruses of genotype II. The results presented here highlight the importance of maintaining strict biosecurity measures and vaccination programs in poultry industries in order to preserve the virulent NDV-free status for commercial flocks in the country. 相似文献
3.
Elisa Crisci Lorenzo Fraile Sonia Valentino Laura Martínez-Guinó Barbara Bottazzi Alberto Mantovani Maria Montoya 《Veterinary microbiology》2014
Long pentraxin 3 (PTX3) is a conserved pattern-recognition secreted protein and a host-defence-related component of the humoral innate immune system. The aim of the present study was to characterize swine PTX3 (SwPTX3) protein expression in influenza virus infected pigs. First, we performed in silico studies to evaluate the cross-reactivity of PTX3 human antibodies against SwPTX3. Secondly, we used in vitro analysis to detect SwPTX3 presence in swine bone marrow dendritic cells (SwBMDC) upon stimulation with different agents by Western blot and immunofluorescence. Finally, the levels of SwPTX3 were assessed in experimental infection of pigs with different strains of influenza virus. This is a novel study where the expression of SwPTX3 was evaluated in the context of a pathogen infection. The initial characterization of SwPTX3 in influenza virus infected pigs contributes to understand the role of PTX proteins in the immune response. 相似文献
4.
Bianca Ferreira Olivieri Camila Urbano Braz Fernando Brito Lopes Elisa Peripolli Rafael Medeiros de Oliveira Silva Rosana Ruegger Pereira da Silva Corte Lucia Galvo de Albuquerque Anglica Simone Cravo Pereira Nedenia Bonvino Stafuzza Fernando Baldi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2021,138(1):80-90
The aim of this study was to identify differentially expressed genes (DEG) in the Longissimus thoracis muscle of Nelore cattle related to fatty acid (FA) profile through RNA sequencing and principal component analysis (PCA). Two groups of 10 animals each were selected containing PC1 and PC2 extreme DEG values (HIGH × LOW) for each FA group. The intramuscular fat (IMF) was compared between cluster groups by ANOVA, and only the sum of monounsaturated FA (MUFA) and ω3 showed significant differences (p < .05). Interestingly, the highest percentage (95%) of phenotypic variation explained by the sum of the first two PC was observed for ω3, which also displayed the lowest number of DEG (n = 1). The lowest percentage (59%) was observed for MUFA, which also revealed the largest number of DEG (n = 66). Since only MUFA and ω3 exhibited significant differences between cluster groups, we can conclude that the differences observed for the remaining groups are not due to the percentage of IMF. Several genes that have been previously associated with meat quality and FA traits were identified as DEG in this study. The functional analysis revealed one KEGG pathway and eight GO terms as significant (p < .05), in which we highlighted the purine metabolism, glycolytic process, adenosine triphosphate binding and bone development. These results strongly contribute to the knowledge of the biological mechanisms involved in meat FA profile of Nelore cattle. 相似文献
5.
Elisa Spoldi Tobias Schwarz Silvia Sabattini Massimo Vignoli Simona Cancedda Federica Rossi 《Veterinary radiology & ultrasound》2017,58(1):29-37
A better understanding of the CT features of different forms of canine and feline adipose tumors would be valuable for improving patient management and treatment. The purpose of this retrospective, cross‐sectional study was to describe and compare the CT features of pathologically confirmed lipomas, infiltrative lipomas, and liposarcomas in a sample of canine and feline patients. A total of 50 animals (46 dogs, four cats) and a total of 60 lesions (23 lipomas, 20 infiltrative lipomas, and 17 liposarcomas) were included in the study. Lipomas appeared as round to oval‐shaped (n = 21), well‐marginated (n = 20) fat‐attenuating lesions. Infiltrative lipomas appeared as homogeneous, fat‐attenuating masses but, unlike lipomas, they were most commonly characterized by an irregular shape (75%; P < 0.001), and linear components, hyperattenuating relative to the surrounding fat (100%; P < 0.05). Liposarcomas were represented exclusively by heterogeneous lesions with soft tissue attenuating components with a multinodular appearance (76.5%; P < 0.05). Regional lymphadenopathy (n = 10) and amorphous mineralization (n = 4) were also observed in association with liposarcomas. Computed tomography can provide useful information regarding disease location, extent, and involvement of the adjacent structures. Tumor definition and shape were the most useful parameters to differentiate between lipomas and infiltrative lipomas. The presence of a heterogeneous mass, with a multinodular soft tissue component and associated regional lymphadenopathy and mineralization, were features favoring a diagnosis of liposarcoma. 相似文献
6.
Fernández-Varón E Villamayor L Escudero E Espuny A Cárceles CM 《Veterinary journal (London, England : 1997)》2006,172(2):302-307
The pharmacokinetics of moxifloxacin was studied following intravenous (IV) and subcutaneous (SC) administration of 5 mg/kg to healthy lactating goats (n = 6). Moxifloxacin concentrations were determined by high performance liquid chromatography assay with fluorescence detection. The moxifloxacin plasma concentration versus time data after IV administration could best be described by a two compartment open model. The disposition of SC administered moxifloxacin was best described by a one-compartment model. The plasma moxifloxacin clearance (Cl) for the IV route was 0.43 +/- 0.02 L/kg (mean +/- SE). The steady-state volume of distribution (Vss) was 0.79 +/- 0.08 L/kg. The terminal half-life (t1/2lambdaz) was 1.94 +/- 0.41 and 2.98 +/- 0.48 h after IV and SC administration, respectively. The absolute bioavailability was 96.87 +/- 10.27% after SC administration. Moxifloxacin penetration from blood to milk was quick for both routes of administration and the high AUCmilk/AUCplasma and Cmax-milk/Cmax-plasma ratios reached indicated a wide penetration of moxifloxacin into the milk. From these data, it appears that a 5 mg/kg SC dose of moxifloxacin would be effective in lactating goats against bacterial isolates with MIC < or = 0.20 microg/mL in plasma and MIC < or = 0.40 microg/mL in milk. 相似文献
7.
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9.
Martin Bonamy Sabrina Kluska Elisa Peripolli Marcos Vinícius Antunes de Lemos Sabrina Thaise Amorim Roberto Jose Vaca Raysildo Barbosa Lbo Letícia Mendes de Castro Carina Ubirajara de Faria Fabio Borba Ferrari Fernando Baldi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(1):15-22
The aim of this study was to estimate genetic parameters for different precocious calving criteria and their relationship with reproductive, growth, carcass and feed efficiency in Nellore cattle using the single‐step genomic BLUP. The reproductive traits used were probability of precocious calving (PPC) at 24 (PPC24), 26 (PPC26), 28 (PPC28) and 30 (PPC30) months of age, stayability (STAY) and scrotal circumference at 455 days of age (SC455). Growth traits such as weights at 240 (W240) and 455 (W455) days of age and adult weight (AW) were used. Rib eye area (REA), subcutaneous fat thickness (SFT), rump fat thickness (RFT) and residual feed intake (RFI) were included in the analyses. The estimation of genetic parameters was performed using a bi‐trait threshold model including genomic information in a single‐step approach. Heritability for PPC traits was moderate to high (0.29–0.56) with highest estimates for PPC24 (0.56) and PPC26 (0.50). Genetic correlation estimates between PPC and STAY weakened as a function of calving age. Correlation with SC455, growth and carcass traits were low (0.25–0.31; ?0.22 to 0.04; ?0.09 to 0.18, respectively), the same occurs with RFI (?0.09 to 0.08), this suggests independence between female sexual precocity and feed efficiency traits. The results of this study encourage the use of PPC traits in Nellore cattle because the selection for such trait would not have a negative impact on reproductive, growth, carcass and feed efficiency indicator traits. Stayability for sexual precocious heifers (PPC24 and PPC26) must be redefined to avoid incorrectly phenotype assignment. 相似文献
10.
Elisa González-Domínguez Vittorio Rossi Sami Jorge Michereff José García-Jiménez Josep Armengol 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(4):849-861
Dispersal of conidia of Fusicladium eriobotryae, the causal agent of loquat scab, was investigated in two loquat orchards in Spain from 2010 to 2012. A volumetric spore sampler, horizontally and vertically orientated microscope slides, and rain collectors were placed in loquat fields to trap conidia of F. eriobotryae. No conidia were collected in the volumetric sampler, and highly variable numbers of conidia were collected in the rain gatherers. Large numbers of conidia were collected by microscope slides, particularly by those held in a horizontal orientation compared with those held in a vertical orientation. Approximately 90 % of the F. eriobotryae conidia were collected during rainy periods. Based on ROC and Bayesian analysis, using ≥ 0.2 mm rainfall as a cut-off value resulted in a high probability of correctly predicting actual conidial dispersal, and had a low probability of failing to predict actual conidial dispersal. Based on the index of dispersion and the binary power law, the incidence of loquat scab on fruit was highly aggregated in space between and within trees, and aggregation was influenced by disease incidence. Our results demonstrate, for the first time, that F. eriobotryae is dispersed mainly in rain splash. The results will be integrated into a mechanistic, weather-driven, disease prediction model that should help growers to minimize fungicide application for the management of loquat scab. 相似文献