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51.
SUMMARY Total plasma carbon dioxide (TCO2) concentrations were measured in Standardbred horses to determine criteria to discriminate between normal horses and horses with excessive TCO2 concentrations on raceday. TCO2 concentrations from stabled horses were distributed normally with a mean of 30.2 mmol/L and a standard deviation of 1.2 (n = 192) while pre-race TCO2 concentrations were not normally distributed. The results indicate that about 50 horses per million are likely to have TCO2 concentrations greater than or equal to 35 mmol/L and that it is extremely unlikely that a normal horse would have a resting TCO2 concentration above 36 mmol/L. These values were associated with sensitivities of 67% and 59%, respectively, and with a specificity of 100%. TCO2 concentrations were relatively stable in blood samples stored at 4°C for 4 days, whereas the TCO2 in specimens stored at room temperature (25°C) and at ambient temperature (16–28°C) declined progressively over 5 days. The accuracy and precision of the Beckman EL-ISE Auto Analyser were acceptable and within the manufacturers specified range. Paired specimens analysed using a Beckman EL-ISE Auto Analyser and a Kodak Dry Chemistry Analyser were not significantly different. However, the measurements made using the Kodak Dry Chemistry Analyser averaged 0.5 mmol/L higher than those analysed on the Beckman EL-ISE. The significance of these sources of variation in TCO2 concentration in relation to the testing of horses for ‘milkshake’ administration are discussed. 相似文献
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Ivan Cruz Maria de Lourdes Corrêa Figueiredo Rafael Braga da Silva Ivana Fernandes da Silva Cristiane deSouza Paula John E. Foster 《国际虫害防治杂志》2013,59(1):83-87
The fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), is a major pest of maize and frequently demands control measures. The timing of insecticide application is a key factor in determining its efficiency, so an experiment was designed to investigate this. Application of insecticide was based on three criteria: (i) the number of trap-caught moths in a Delta-type trap with a commercial sex pheromone lure placed in the center of the target area, soon after plant emergence; (ii) the percentage of plants exhibiting pinhole-type damage (10% or 20%) and (iii) the percentage of plants exhibiting shot hole-type damage (10% or 20%) compared to a check plot without any control measures. We found that the number of trap-caught moths was, compared to the other methods, the best means of deciding on insecticide application in maize to control the fall armyworm. Using pheromone traps, we obtained the best performance of the insecticide Spinosad, causing >90% larval mortality. Without insecticide application, maize yield reduction due to fall armyworm larva damage was 39%. 相似文献
54.
Fabio R. Braga Rogério O. Carvalho André R. Silva Jackson V. Araújo Luiza N. Frassy Andrea Lafisca Filippe E. F. Soares 《Tropical animal health and production》2014,46(3):571-574
Biological control of gastrointestinal nematodiasis in ruminants is an alternative to reduce the number of infective larvae. The fungal isolates predatory activity preservation is a basic requirement for the success of this control type. The aim of this work is to evaluate the predatory capacity of the fungus Arthrobotrys robusta (isolate I-31), preserved on silica gel on infective larvae of Haemonchus contortus under laboratory conditions on 2 % water agar (2 % WA). In this essay, A. robusta storage on silica gel showed successful predatory activity on H. contortus L3 larvae (p?<?0.01) compared to the control group. Nematophagous fungi were not observed in the control group during the experiment. There was a significant reduction (p?<?0.01) of 73.84 % in the means of H. contortus (L3) recovered from treatment with isolate I-31 compared to the control without fungi. Results indicate that A. robusta (I-31) could survive stored on silica gel for at least 7 years and keep its predatory activity on H. contortus (L3). 相似文献
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Salmon D Vanwalleghem G Morias Y Denoeud J Krumbholz C Lhommé F Bachmaier S Kador M Gossmann J Dias FB De Muylder G Uzureau P Magez S Moser M De Baetselier P Van Den Abbeele J Beschin A Boshart M Pays E 《Science (New York, N.Y.)》2012,337(6093):463-466
The parasite Trypanosoma brucei possesses a large family of transmembrane receptor-like adenylate cyclases. Activation of these enzymes requires the dimerization of the catalytic domain and typically occurs under stress. Using a dominant-negative strategy, we found that reducing adenylate cyclase activity by about 50% allowed trypanosome growth but reduced the parasite's ability to control the early innate immune defense of the host. Specifically, activation of trypanosome adenylate cyclase resulting from parasite phagocytosis by liver myeloid cells inhibited the synthesis of the trypanosome-controlling cytokine tumor necrosis factor-α through activation of protein kinase A in these cells. Thus, adenylate cyclase activity of lyzed trypanosomes favors early host colonization by live parasites. The role of adenylate cyclases at the host-parasite interface could explain the expansion and polymorphism of this gene family. 相似文献
57.
Aliny Simony Ribeiro José Ubirajara Vieira Moreira Pedro Henrique Braga Pierozzi Breno Francovig Rachid José Francisco Ferraz de Toledo Carlos Alberto Arrabal Arias Rafael Moreira Soares Claudia Vieira Godoy 《Euphytica》2007,157(1-2):15-25
The objective of this study was to investigate the genetic mechanisms of soybean resistance to Asian rust (Phakopsora pachyrhizi Syd. & P. Syd). F2 and F3 generations from 15 diallel crosses involving six soybean cultivars, FT-2, EMBRAPA 48, BRS 154,
BRS 184, BRS 214, BRS 231, were used to analyze the genetic control of Asian rust resistance in the soybean parents tested.
Genetic models were fitted to means and variances of the generations tested in a completely randomized field experiment with
5,700 hill plots. The experiment was spray-inoculated twice with an isolate that was first detected during the 2002/03 season
in Mato Grosso (MT) State and presently prevail in Central Brazil, at a six-day interval, on borders rows and on the useful
area, respectively, with a 104 spores/ml distilled H2O suspension. Assessments were made using a diagrammatic scale for disease severity at seven and 39 days after the first detection
of Asian rust in the experiments. Evaluations made in the second assessment (39 days) discriminated better between genotypes.
Selection at early plant developmental stages may not result in adult resistant plants. Cultivar FT-2, which had presented
monogenic resistance to a rust isolated that prevailed in the first two years of rust occurrence in Brazil, showed no resistance
to the MT State rust strain used in this experiment, but eleven crosses showed genetic variability for resistance in the second
assessment. Soybean rust resistant genes showing predominantly additive effects are dispersed among parents. Narrow sense
heritability values ranging from 0.42 to 0.74 at the F3 family level in the second assessment suggested that selection of
resistant genotypes is feasible. 相似文献
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NP STEWART NF STANDFAST† FC BALDOCK‡ DJ REID AJ de VOS† 《Australian veterinary journal》1992,69(3):59-61
The distribution and prevalence of Thelleria buffeli in Queensland cattle were investigated using serum samples and blood films collected primarily for brucellosis surveillance and tick fever diagnosis. Serums from 8654 cattle from 357 farms throughout Queensland were examined by an indirect fluorescent antibody test for antibody to T buffeli. In addition, 347 peripheral blood films collected from 147 farms in south-eastern Queensland were examined for piroplasms of T buffeli. The overall herd and animal prevalences for T buffeli were 75% and 41%, respectively. There was significant variation among regions in both herd and animal prevalences (P less than 0.001). Herd and animal prevalences were highest in the north and east decreasing westward. The results indicate that T buffeli is more widespread in Queensland than previously thought. 相似文献
60.
Belinelli Eduardo Oliveira Fantin Lucas Henrique Canteri Marcelo Giovanetti Braga Karla Cirilo Eliandro Rodrigues Romeiro Neyva Maria Lopes Natti Paulo Laerte 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):979-990
European Journal of Plant Pathology - Phakopsora pachyrhizi is a biotrophic fungus that needs living plant tissue in order to survive. The fungus causes Asian rust on soybean and costs billions of... 相似文献