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1.
Trilostane is considered an efficacious and safe medication for canine pituitary-dependent hyperadrenocorticism (PDH). Its recommended frequency of administration is once daily. In this prospective study, the efficacy, toxicity, and long-term outcome of trilostane administered twice daily per os were evaluated in 44 dogs with PDH. Mean initial dose was 3.1 mg/kg q 12 hours, and mean final dose was 3.2 mg/kg q 12 hours. The final total daily dose was lower than previously reported for once-daily administration. The mean survival time for affected dogs was 930 days.  相似文献   
2.
A cross-sectional study was carried out to determine the seroprevalence and risk factors associated with bovine respiratory syncytial virus (BRSV) infection in non-vaccinated dairy and dual-purpose cattle herds from Ecuador. A total of 2,367 serum samples from 346 herds were collected from June 2008 to February 2009. A questionnaire, which included variables related to cattle, health, management measures, and the environment, was filled out in each herd. Presence of antibodies against BRSV was analyzed using a commercial indirect ELISA test. A logistic regression model was used to determine risk factors associated with BRSV at herd level. The individual seroprevalence against BRSV in non-vaccinated herds in Ecuador was 80.48% [1,905/2,367; 95% confidence interval (CI)?=?78.9-82.1]. The herd prevalence was 91.3% (316/346; 95% CI?=?88.3-94.3), and the intra-herd prevalence ranged between 25% and 100% (mean, 90.47%). The logistic regression model showed that the existence of bordering cattle farms, the dual-purpose farms, and the altitude of the farm (more than 2,338?m above sea level) were risk factors associated with BRSV infection. This is the first study about BRSV prevalence in Ecuador. It shows the wide spread of the BRSV infection in the country. The risk factors found will help to design effective control strategies.  相似文献   
3.
A novel peptide, RsXXIVA, was isolated from the venom duct of Conus regularis, a worm-hunting species collected in the Sea of Cortez, México. Its primary structure was determined by mass spectrometry and confirmed by automated Edman degradation. This conotoxin contains 40 amino acids and exhibits a novel arrangement of eight cysteine residues (C-C-C-C-CC-CC). Surprisingly, two loops of the novel peptide are highly identical to the amino acids sequence of ω-MVIIA. The total length and disulfide pairing of both peptides are quite different, although the two most important residues for the described function of ω-MVIIA (Lys2 and Tyr13) are also present in the peptide reported here. Electrophysiological analysis using superior cervical ganglion (SCG) neurons indicates that RsXXIVA inhibits CaV2.2 channel current in a dose-dependent manner with an EC50 of 2.8 μM, whose effect is partially reversed after washing. Furthermore, RsXXIVA was tested in hot-plate assays to measure the potential anti-nociceptive effect to an acute thermal stimulus, showing an analgesic effect in acute thermal pain at 30 and 45 min post-injection. Also, the toxin shows an anti-nociceptive effect in a formalin chronic pain test. However, the low affinity for CaV2.2 suggests that the primary target of the peptide could be different from that of ω-MVIIA.  相似文献   
4.
We have carried out an aetiological and pathological study of an outbreak of septicaemia caused by the O165 serogroup of Escherichia coli in Japanese quail (Coturnix coturnix japonica) which resulted in high mortality (90%). After treatment with amoxicilin in drinking water (200 mg/l), morbility and mortality rates dropped markedly. Microbiological studies showed that the organism responsible was an atypical E. coli strain, on the basis of the non-fermentation of lactose (ONPG-), which belonged to the O165 serogroup and was highly virulent for 1-day-old chickens.  相似文献   
5.
The sea louse (Caligus rogercresseyi) is the most significant parasitic pathogen in Chilean salmon farms, and it infects farmed salmon and native host fish. Fecundity is one of the most important parameters for understanding the population dynamics of a species; however, this information is scarce for this parasite. The fecundity of C. rogercresseyi females collected from native hosts (Eleginops maclovinus) captured near salmon farms in southern Chile was measured to evaluate the reproductive output of this parasite on this host fish. From June 2008 to May 2009, 212 specimens of E. maclovinus were examined. Each fish was measured, and all its parasites were collected, sorted and counted. Seventy‐nine ovigerous C. rogercresseyi females (OFs) were measured. Total body length, egg string length and total number of eggs per string were recorded for each parasite. Ovigerous females body length varied between 3.9 and 5.0 mm. Fecundity varied between 12 and 56 eggs string?1, and it was correlated with OF body length. Temporal variations in OF fecundity were explained by co‐variation in OF body length, but not by month. Ovigerous females on E. maclovinus were smaller and showed lower fecundity than OFs on farmed salmon. Our results suggest that native hosts play a secondary role in C. rogercresseyi egg production in Codigue bay.  相似文献   
6.
ABSTRACT: Although the importance of wild ruminants as potential reservoirs of bluetongue virus (BTV) has been suggested, the role played by these species in the epidemiology of BT in Europe is still unclear. We carried out a serologic and virologic survey to assess the role of wild ruminants in the transmission and maintenance of BTV in Andalusia (southern Spain) between 2006 and 2010.A total of 473 out of 1339 (35.3%) wild ruminants analyzed showed antibodies against BTV by both ELISA and serum neutralization test (SNT). The presence of neutralizing antibodies to BTV-1 and BTV-4 were detected in the four species analyzed (red deer, roe deer, fallow deer and mouflon), while seropositivity against BTV-8 was found in red deer, fallow deer and mouflon but not in roe deer. Statistically significant differences were found among species, ages and sampling regions. BTV RNA was detected in twenty-one out of 1013 wild ruminants (2.1%) tested. BTV-1 and BTV-4 RNA were confirmed in red deer and mouflon by specific rRT-PCR.BTV-1 and BTV-4 seropositive and RNA positive wild ruminants, including juveniles and sub-adults, were detected years after the last outbreak was reported in livestock. In addition, between the 2008/2009 and the 2010/2011 hunting seasons, the seroprevalence against BTV-1, BTV-4 and BTV-8 increased in the majority of provinces, and these serotypes were detected in many areas where BTV outbreaks were not reported in domestic ruminants. The results indicate that wild ruminants seem to be implicated in the dissemination and persistence of BTV in Spain.  相似文献   
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In this report, the effect of temperature on the calcium content of Quality Protein Maize (QPM H-368C) during the nixtamalization process as a function of the steeping time for three cooking temperatures (72, 82, and 92°C) is presented. Also, for the first time, we report in physico-chemical terms the end of the cooking stage during the nixtamalization process that was established when the moisture content in corn kernels reached a value of 36% (w/w) with a lime concentration of 1% (w/v), independent of the cooking temperature. Atomic absorption spectroscopy was used to determine the calcium concentration in the whole kernel and in its different anatomical components (pericarp, endosperm, and germ) as well as in 10% of the outermost layers, the next 10%, and the remaining 80% of the endosperm as a function of the steeping time. It was found that if the cooking temperature increases, the calcium content increases also. For steeping times in the range of 5–7 hr, a relative maximum was found in the calcium contents of 0.24, 0.21, and 0.18% (w/w) in QPM H-368 flours at 92, 82, and 72°C, respectively. Calcium was found in the most external layers in the endosperm and minimum diffusion occurs in the internal 80%. Phosphorous was measured by using UV spectroscopy and the results showed that it remains constant at 0.24% throughout the process. Scanning electron microscopy analysis was used to explain the calcium ion diffusion in the kernel. The physical changes in the pericarp govern the calcium diffusion process.  相似文献   
10.
Agroforestry systems are reported as climate‐resilient productive systems, but it is yet unclear how tree shade affects crops performance. The aim of this work was to assess how the phenology, plant traits and grain yield of wheat and barley were affected by shade. In an open greenhouse experiment, we cultivated in pots nine cultivars differing in precocity for each species and imposed three artificial shading levels (S0 ~ 0%, S1 ~ 25%, S2 ~ 50%) at the start of cereal booting. Our results showed that shade speeded up first growth stages in both species, until the starting of milk development. Barley showed consistent phenological responses to the three irradiance levels among cultivars, but not wheat that showed larger phenological differences among cultivars at moderate shade. Deep shade prolonged the time needed for wheat grain ripening. Both species increased grain yield by 15%–20% with shade, driven by shade‐acclimations of plant traits that differed among species. For wheat, grain yield was determined by the assemblage of traits that contribute to yield, such as grain weight, precocity and non‐photochemical quenching, while, for barley, SPAD value, precocity to reach phenological stages, grains per spike and plant height had the strongest influence. These traits varied widely among cultivars and seem of interest to identify best suited cultivars for shading conditions of Mediterranean agroforestry systems.  相似文献   
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