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Detection of bovine Babesia spp. and Anaplasma marginale is based on the reading of Giemsa-stained blood or organ smears, which can have low sensitivity. Our aim was to improve the detection of bovine Babesia spp. and A. marginale by validating a multiplex PCR (mPCR). We used 466 samples of blood and/or organs of animals with signs and presumptive autopsy findings of babesiosis or anaplasmosis. The primers in our mPCR amplified the rap-1a gene region of Babesia bovis and B. bigemina, and the msp-5 region of A. marginale. We used a Bayesian model with a non-informative priori distribution for the prevalence estimate and informative priori distribution for estimation of sensitivity and specificity. The sensitivity and specificity for smear detection of Babesia spp. were 68.6% and 99.1%, and for A. marginale 85.6% and 98.8%, respectively. Sensitivity and specificity for mPCR detection for Babesia spp. were 94.2% and 97.1%, and for A. marginale 95.2% and 92.7%, respectively. Our mPCR had good accuracy in detecting Babesia spp. and A. marginale, and would be a reliable test for veterinarians to choose the correct treatment for each agent.  相似文献   
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A young intact female dog was presented with urinary incontinence. Abdominal ultrasound revealed the presence of hyperechoic linear structures within the cranial vagina suggestive of foreign material. A computed tomography (CT) retrograde vaginourethrogram demonstrated the presence of a fistulous tract between the urethra and vagina. A presumptive diagnosis of urethrovaginal fistula due to migration of foreign material was made. The grass awn was removed with vaginoscopic‐guided retrieval. Fourteen days later, surgical repair of the fistula and an ovariohysterectomy were done. This case report emphasizes the usefulness of CT for diagnosis and precise anatomical localization of genitourinary tract fistulas.  相似文献   
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This paper evaluates the sensitivity of two different methods of water stress detection in a simulated patch of pasture grown in a greenhouse. The performance of two indices, based respectively on canopy temperature and soil water content values — the latter gauged by means of a time domain reflectometry (TDR) system, was assessed against actual evapotranspiration, measured by a very accurate weighing system. Both methods were able to detect water shortage by the time transpiration was reduced to some 80% of its potential value. The soil-based index, however, relied on the estimate of root water extraction rate, which may not be known. It is concluded that detection of water shortage by means of a canopy temperature-based stress index is to be preferred to measuring soil water deficits by time domain reflectometry, despite the accuracy of the TDR-based soil water content estimate.  相似文献   
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Flower initiation date and readiness to flowering in buds of different age were studied in ‘Fino de Jete’ cherimoya (Annona cherimola) cultivar in order to establish the limits for the manipulation of its flowering date. Flower initiation was analyzed by light and scanning electron microscopy (SEM) collecting axillary buds from May to the following February, whereas the bud readiness to produce perfect flowers was determined by forcing buds of different age to sprout by means of leaf removal and tipping the new growth. SEM images confirm that cherimoya buds are differentiated into flowers almost a year before blooming. In this regard, axillary buds have already formed the sepals when the subtending leaf has just begun unfolding (week 0), while the petals are clearly visible in 1-week-old buds. Sectioning of paraffin-embedded buds illustrate that cherimoya buds are in fact a bud complex that 1 week after its inception comprises 4–5 buds of different size of which the two largest ones are reproductive, while the 2–3 smallest buds often remain undifferentiated at that time. The high capacity of flowering expressed by young buds that have been forced to grow proves that cherimoya meristems are early competent for flowering. No differences in fertility or in the time needed to reach anthesis after leaf removal were found among buds of different ages. Node position had no effect on bud break and flowering potential. The early flower initiation in cherimoya deduced from this work opens a wide temporal window for the experimental manipulation of flowering and harvest dates in this crop.  相似文献   
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Plant Foods for Human Nutrition - Sorghum is a major cereal crop with various agronomic advantages, contains health-promoting compounds and is gluten-free. There is a growing tendency to use...  相似文献   
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Argentine hake (Merluccius hubbsi) was stored chilled for 8 days. The evolution of fluorescence of the aqueous and organic extracts of muscle during storage at 4°C was studied and correlated with common damage indices; pH, total volatile basic nitrogen, free fatty acids, and the fluorescence intensity of the aqueous phase showed a good correlation with storage time. The excitation-emission matrices of the aqueous extracts were also obtained. A fluorescence landscape that could be attributed to tryptophan decreased with storage time, meanwhile a peak (around 340 and 400 nm for excitation and emission wavelengths, respectively) is developed during chilled storage.  相似文献   
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