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21.
Zymoseptoria tritici ascospores and pycnidiospores are considered the main forms of primary and secondary inoculum, respectively, in septoria tritici blotch epidemics. The pathogenicity of the two types of spores of the same genotypic origin were compared through a two‐stage inoculation procedure in controlled conditions. Adult wheat leaves were inoculated with ascospores collected from field sources, yielding 119 lesions; pycnidiospores collected from 12 lesions resulting from these ascospore infections were then used for inoculation. Lesion development was assessed for 5 weeks; latent period, lesion size, and pycnidium density were estimated for different isolates. The latent period was calculated as the maximum likely time elapsed between inoculation and either the appearance of the majority of the sporulating lesions (leaf scale) or the appearance of the first pycnidia (lesion scale). The latent period was significantly longer (c. 60 degree‐days, i.e. 3–4 days) after infection with ascospores than with pycnidiospores. No difference was established for lesion size and density of pycnidia. A comparison with other ascomycete fungi suggested that the difference in latent period might be related to the volume of spores and their ability to cause infection. Fungal growth before the appearance of lesions may be slower after inoculation with an ascospore than with a pycnidiospore. The mean latent period during the very beginning of epidemics, when first lesions are mainly caused by ascospores, may be longer than during spring, when secondary infections are caused by pycnidiospores. Disease models would be improved if these differences were considered.  相似文献   
22.
The two most common haemotropic Mycoplasma of cats, Mycoplasma haemofelis and 'Candidatus Mycoplasma haemominutum' have been identified using molecular techniques in all continents, except Antarctica. We report the first molecular characterization in South America of a dual infection with M haemofelis and 'Candidatus Mycoplasma haemominutum' in three domestic cats. The 16S ribosomal RNA gene was amplified in three anaemic cats in which haemoplasma organisms were seen attached to the erythrocytes in the peripheral blood smear. Bands of the expected size for M haemofelis and 'Candidatus Mycoplasma haemominutum' were observed in all three cats. The 393 bp segment of one of the amplicons had a similarity value of 100% to M haemofelis, whereas the other amplicon, a 192 bp segment, was 100% similar to 'Candidatus Mycoplasma haemominutum'. After diagnosis, two cats received blood transfusion and they were all treated with doxycycline. All three cats recovered uneventfully.  相似文献   
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The purpose of this study was to find out if an LMA (#1 LMA‐Classic) would provide a better airway than a face mask in spontaneously breathing anesthetized rabbits, and to test if it could be used for mechanically controlled ventilation. Sixteen rabbits (4.1 ± 0.8 kg, mean ± SD) were assigned randomly to three treatment groups; face mask with spontaneous ventilation (FM‐SV; n = 5), LMA with spontaneous ventilation (LMA‐SV; n = 5), and LMA with controlled ventilation (LMA‐CV; n = 6). Rabbits were anesthetized in dorsal recumbency using a circle circuit at constant ET isoflurane (2.3%, Datex airway gas monitor) and constant rectal temperature (38.85 °C) for 2 hours. PaCO2, PaO2, minute volume, tidal volume (Wright's respirometer), and Pe CO2 were measured at 15 minute intervals. Two individuals in the FM‐SV group had PaCO2 >100 mm Hg (>13.3 kPa). One rabbit in the FM‐SV had PaO2 <80 mm Hg (<10.7 kPa). All FM‐SV rabbits showed signs of airway obstruction and two were withdrawn from the study at 45 and 90 minutes, respectively, because of cyanosis. Tidal volume could not be measured in the FM‐SV group. No signs of airway obstructions were observed in either of the LMA groups. Four rabbits in the LMA‐CV group developed gastric tympany, and one of these refluxed after 110 minutes. The significance of differences between the two spontaneously breathing groups and between the two LMA groups were measured using Wilcoxon's rank sum test (with significance assumed at p < 0.05). There were no statistical differences between FM‐SV and LMA‐SV in any variable tested. PaCO2 and Pe ′CO2 were less in the LMA‐CV group than in the LMA‐SV group, while PaO2, tidal volume, and minute volume were all more. We conclude that biologically, the LMA provides a better airway than the face mask during spontaneous breathing and that it can be used for IPPV, but that gastric tympany is likely to occur during IPPV.  相似文献   
24.
Blood cell morphology and count are not uniform across species. Recently, between‐species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa, and this finding was interpreted in the context of the metabolic theory. In the present study, we examined the numbers and the size of blood cells in 2 species of monitor lizards, the mangrove‐dwelling monitor (Varanus indicus) and the savannah monitor (V. exanthematicus), and we compared these traits in individuals of different body size. The results revealed that during the course of ontogeny, the size of red blood cells increases with body mass. Because the mass‐specific metabolic rate decreases with body size and the cell volume‐to‐surface ratio decreases with the cell size, changes in the erythrocyte size might be the result of oxygen transport adjustment.  相似文献   
25.
Gastrointestinal helminthiasis represents an obstacle to goat raising, causing severe damage to herds such as growth retardation, weight loss, and even death. In this study, we aimed to determine the prevalence and risk factors associated to goat gastrointestinal helminthiasis in the Sertão region of Paraíba State, Brazil. A total of 256 goats from 54 farms were systematically sampled. Blood and fecal samples were collected from each animal for egg per gram (EPG), larval culture, and packed cell volume (PCV) analyses. We found that 79.3 % of the goats investigated were parasitized with gastrointestinal helminths. Significant correlation (p?=?0.004) was observed between the EPG and PCV of the animals studied, and it was observed that the EPG increases as the PCV decreases. In the larval culture, the most prevalent helminth was Haemonchus sp. (83.2 %). Age and sex were significant variables (p?≤?0.20) for the development of gastrointestinal helminths: 86.8 % of animals over 36 months of age and 81.7 % of females were infected. The variable type of animal exploitation was also significant, with 90.3 % (p?≤?0.20) of the animals presenting double suitability (milk and meat). The Sertão region of Paraíba State presents high prevalence of gastrointestinal helminthiasis in goats, and age and type of animal exploitation are the most relevant risk factors to the development of these parasites.  相似文献   
26.
A plant breeding program is a long-term investment. Therefore, periodic assessment of the effectiveness of a breeding strategy is essential to maximize genetic gains per unit of time and resource invested. In this work, we assessed the effectiveness of the early-generation testing (EGT) approach used in the upland rice (Oryza sativa L.) breeding program at Embrapa (Brazilian Agricultural Research Corporation), Brazil, estimating the genetic progress achieved for three traits in two distinct phases, spanning 15 years. In the first phase (from 2003 to 2010), it was used the bulk method within F3 progenies with prior testing of F2 crosses, while in the second phase (from 2010 to 2017), it was used the bulk method within F2 progenies. The dataset comprised 70 yield trials, involving 1884 F3:5 progenies (phase I) and 925 F2:4 progenies (phase II) from an elite population, and 10 check cultivars, evaluated for grain yield (GY), plant height (PH) and days to flowering (DTF). For estimating the genetic gain, we adapted a generalized linear regression method to compute bi-segmented linear regression coefficients. Desirable genetic gains were achieved only for GY in both phases of the breeding program, with 78.75 kg ha?1 year?1 (2.68%) in the first phase, and 53.78 kg ha?1 year?1 (1.54%) in the second phase. These results show the effectiveness of EGT, especially via bulk method within F3 progenies with prior testing of F2 crosses, applied to upland rice breeding. Some refinements are discussed in the method to make it more cost-effective and more efficient in achieving genetic gains.  相似文献   
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Nephrolithiasis has rarely been reported in marine mammals. During 2004 and 2005, two cases of nephrolithiasis were diagnosed during routine necropsy examination, one in a northern elephant seal (Mirounga angustirostris) and one in a California sea lion (Zalophus californianus). Nephroliths were found throughout both kidneys during necropsy examination, varying in size from 1-10 mm in diameter in the northern elephant seal and from 1-15 mm in diameter in the California sea lion. Necropsy and histopathology revealed nephroliths in association with renal pelvic dilation and pyelonephritis in both animals. In addition, hydronephrosis was noted in the sea lion. Nephroliths were composed of uric acid and ammonium urate in the northern elephant seal and of ammonium urate in the California sea lion. The underlying disease leading to nephrolith formation was not determined; however, it is hypothesized that unknown metabolic derangements due to morphologic or physiologic differences may have played a role. This is the first report of urate nephrolithiasis in the California sea lion and northern elephant seal.  相似文献   
30.
Background: Ehrlichiosis is a multisystemic disease with the potential to cause cardiomyocyte injury in naturally infected dogs.
Hypothesis: Myocardial injury occurs in dogs infected with Ehrlichia canis .
Animals: One-hundred and ninety-four dogs from Brazil with clinical and laboratory abnormalities indicative of ehrlichiosis. Sixteen healthy dogs served as controls.
Methods: Electrocardiogram, echocardiogram, noninvasive blood pressure measurement, and serum cardiac troponin I (cTnI) concentrations were evaluated. Serologic assays and PCR determined the exposure and infection status for E. canis, Anaplasma spp., Babesia canis vogeli, Bartonella spp., Borrelia burgdorferi, Dirofilaria immitis, Ehrlichia chaffeensis, Ehrlichia ewingii, Leishmania chagasi , and spotted-fever group Rickettsia . Dogs were assigned to groups according to PCR status: E. canis infected, infected with other vector-borne organisms, sick dogs lacking PCR evidence for infection, and healthy controls.
Results: E. canis -infected dogs had higher serum cTnI concentrations than controls (median: 0.04 ng/dL; range 0.04–9.12 ng/dL; control median: 0.04 ng/dL; range: 0.04–0.10 ng/dL; P = .012), and acute E. canis infection was associated with myocardial injury (odds ratio [OR]: 2.67, confidence interval [CI] 95%: 1.12–6.40, P = .027). Severity of anemia was correlated with increased risk of cardiomyocyte damage ( r = 0.84, P < .001). Dogs with clinical signs of systemic inflammatory response syndrome (SIRS) were at higher risk for myocardial injury than were other sick dogs (OR: 2.55, CI 95%: 1.31–4.95, P = .005).
Conclusions and Clinical Importance: Acute infection with E. canis is a risk factor for myocardial injury in naturally infected Brazilian dogs. Severity of anemia and SIRS might contribute to the pathophysiology of myocardial damage.  相似文献   
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