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1.
An outbreak of giardiasis was observed in a sheep farm in Central Italy. Infected lambs (30-90 days of age) showed a malabsorption syndrome, decreased weight gain and impairment in feed efficiency. The most relevant clinical sign was the excretion of malodorous and poorly formed faeces, whereas diarrhoea was rarely observed in the flock. Laboratory investigations revealed the presence of Giardia in affected animals, while no other significant viral, bacterial or parasitic pathogens were identified in faeces or tissue samples. A mild to severe infiltrative enteritis with eosinophils, lymphocytes and plasma cells was detected in histological sections of the gut. Giardia parasites collected from duodenal aspirates were typed as Giardia duodenalis Assemblage B, by PCR amplification and sequencing of the TPI gene. Treatment with fenbendazole at a dose of 10mg/kg for 3 consecutive days, successfully cleared the infection. These results show that G. duodenalis can cause significant economic losses in sheep farming.  相似文献   
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OBJECTIVE: To compare the mechanical shear strengths and stiffnesses obtained from in vitro testing of a simulated complete third carpal bone (C3) frontal plane radial facet slab fracture (osteotomy) stabilized with either a 4/5 Acutrak (AT) compression screw or a 4.5-mm AO cortical bone (AO) screw inserted in lag fashion. Drilling, tapping, and screw insertion torques, forces, and times also were compared between AT and AO implants. STUDY DESIGN: In vitro biomechanical assessment of site preparation, screw insertion, and shear failure test variables of bone screw stabilized simulated C3 slab fracture in paired cadaveric equine carpi. SAMPLE POPULATION: Eight pairs of cadaveric equine C3 without orthopedic abnormalities. METHODS: Standardized simulated C3 slab fractures were repaired with either AO or AT screws (AO/C3 and AT/C3 groups, respectively). Drilling, tapping, and screw insertion torques, forces, and times were measured with a materials testing machine for each screw type. Repaired specimens were tested in axially oriented shear until failure. Paired Students t-tests were used to assess differences between site preparation, screw insertion, and shear testing variables. Significance was set at P <.05. RESULTS: There were no significant differences in bone fragment measurements of the standardized simulated C3 slab fractures created for AO or AT screws. There were no significant differences for mean and maximum drilling torques; however, the tapered AT drill had greater maximum drilling force compared with the 3.2-mm and 4.5-mm AO drill bits. Mean insertion torque and force measured from the self-tapping AT screw were not significantly different compared with the 4.5-mm AO tap. There were no significant differences in maximum screw torque among constructs. Total procedure time was significantly longer for the AT group (5.8 +/- 1.6 minutes) compared with the AO group (2.9 +/- 1.1 minutes; P =.001). AT stabilized specimens had significantly greater mean +/- SD initial shear stiffness (3.64 +/- 1.08 kN/mm) than AO specimens (1.64 +/- 0.73 kN/mm; P =.005). All other shear mechanical testing variables were not statistically different among screw types. CONCLUSION: The 4/5 Acutrak insertion technique was accurate and safe, and the AT screw effectively stabilized simulated equine C3 frontal plane slab fractures. When tested in shear, this screw type was mechanically comparable to the 4.5-mm AO screw; however, AT constructs had greater initial shear stiffness. Initial shear stiffness was likely an indirect measure of interfragmentary compression, and thus may indicate that the AT screw provides a more rigid fixation for frontal plane C3 slab fractures in horses. CLINICAL RELEVANCE: Considering the comparable mechanical behavior, greater initial shear stiffness for AT screw stabilized C3 slab fracture fragments, the ability to accurately insert the screw with the aid of a guide pin, and the potential for less persistent soft tissue irritation with the headless screw design, the 4/5 tapered AT screw is an attractive alternative for repair of C3 slab fractures in horses.  相似文献   
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OBJECTIVE: To compare isolated limb retrograde venous injection (ILRVI) and isolated limb infusion (ILI) for delivery of amikacin to the synovial fluid of the distal interphalangeal and metacarpophalangeal joints and to evaluate the efficacy of use of an Esmarch tourniquet in standing horses. ANIMALS: 6 healthy adult horses. PROCEDURES: Horses were randomly assigned in a crossover design. In ILRVI, the injection consisted of 1 g of amikacin diluted to a total volume of 60 mL administered during a 3-minute period. In ILI, the infusion consisted of 1 g of amikacin diluted to 40 mL administered during a 3-minute period followed by administration of boluses of diluent (82 mL total) to maintain vascular pressure. During ILI, the infusate and blood were circulated from the venous to the arterial circulation in 5-mL aliquots. Synovial fluid and serum samples were obtained to determine maximum amikacin concentrations and tourniquet leakage, respectively. RESULTS: Both techniques yielded synovial concentrations of amikacin > 10 times the minimum inhibitory concentration (MIC) for 90% of isolates (80 microg/mL) and > 10 times the MIC breakpoint (160 microg/mL) of amikacin-susceptible bacteria reported to cause septic arthritis in horses. These values were attained for both joints for both techniques. Esmarch tourniquets prevented detectable loss of amikacin to the systemic circulation for both techniques. CONCLUSIONS AND CLINICAL RELEVANCE: Both techniques reliably achieved synovial fluid concentrations of amikacin consistent with concentration-dependent killing for bacteria commonly encountered in horses with septic arthritis. Esmarch tourniquets were effective for both delivery techniques in standing horses.  相似文献   
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Daily multiplication factor (number of daughter lesions per mother lesion per day) values were experimentally measured in four replications of a monocyclic experiment on angular leaf spot (ALS) of bean, where sources of inoculum were artificially established within a bean canopy, on the ground (defoliated infected leaves), or both. Daily multiplication factor of lesions in the canopy (DMFRc) was higher than that of infectious, defoliated tissues (DMFRd) in all replications. Both DMFRc and DMFRd were strongly reduced under dry compared to rainy conditions. Under rainy conditions for spore dispersal DMFRd was about two to three times smaller than DMFRc. Defoliated leaves may nevertheless represent a significant source of infection, depending on the amount of infectious tissues. Mother lesions within the canopy generated more daughter lesions in the medium (or lower) layers of the canopy than at its upper level (DMFRc higher at the medium and lower layers of a canopy), whereas DMFRd values seemed to decrease with height in the canopy. A mechanistic simulation model that combines host growth and disease-induced defoliation was designed to simulate the respective contributions of the two components of the dual inoculum source of a diseased canopy (infected foliage and defoliated infectious tissues), and varying infectious periods in both sources. Simulations suggest that higher DMFRc values have a large polycyclic effect on epidemics whereas that of DMFRd is small, and that large effects of the infectious period of lesions in the canopy are found when DMFRc is high. Simulations using experimentally measured DMFRc and DMFRd values indicated much stronger epidemics in rainy compared to dry conditions for spore dispersal, but disease persistence in the latter. The implications of considering a dual source of inoculum in the course of a polycyclic process are discussed with respect to epidemic thresholds.  相似文献   
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A 5-year-old Hereford cow was donated to Oregon State University, College of Veterinary Medicine. Two weeks before presentation the cow was treated by a left-flank laparotomy to correct a uterine torsion that revealed an excessive amount of abdominal fluid and a full term dead fetus. Ultrasonographic evaluation of the right cranioventral thoracic cavity was performed owing to physical examination (muffled heart sounds, areas of silence) and thoracocentesis findings suggestive of pleuritis. Ultrasonography revealed hypoechoic pleural effusion and a mass of mixed echogenicity visible within the right atrial lumen extending into the cranial vena cava. A diagnosis of cranial vena cava thrombosis was demonstrated at necropsy. The clinical, ultrasonographic, and pathological features of this less common condition (cranial vena cava thrombosis) in cattle are discussed.  相似文献   
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Progression from the juvenile to mature phase in woody plants is accompanied by changes in characteristics as diverse as adventitious rooting capacity, leaf morphology, canopy architecture, wood anatomy and reproductive development. Many concepts of phase change, the intensity and duration of changes that occur during the phase transition, and the practical consequences of plant maturation for growth and development, are poorly understood. Little is known about the physiological and environmental control of maturation in woody plants compared with herbaceous plants, and reliable markers of phase state have only been developed for a few species, mainly conifers. Understanding the mechanisms and forms of phase change is a prerequisite for achieving maturation or rejuvenation for applications such as seed production or clonal propagation. This review describes concepts, terminology and consequences of phase change, combining theoretical and practical aspects of tree maturation that relate to clonal forestry.  相似文献   
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Carrot root oil (SCO), obtained by supercritical fluid carbon dioxide (SC-CO2) extraction, was characterized and compared to a commercial carrot oil (MCO) and a virgin olive oil (VOO) (cv. Coratina). SCO showed much higher contents of carotenes, phenolics, waxes, phytosterols, and sesquiterpene and monoterpene volatiles. In SCO, the most prominent components present in the fully investigated analytical fractions (fatty acids, triglycerides, waxes, phytosterols, long-chain aliphatic alcohols, superior triterpene alcohols, and volatiles) were, respectively, linolenic acid, trilinolein, waxes C38, beta-sitosterol, campesterol and stigmasterol, 1-hexacosanol, 24-methylencycloartanol and cycloartenol, beta-caryophyllene, alpha-humulene, alpha-pinene, and sabinene. In VOO, the major constituents of the above analytical classes were, respectively, oleic acid, trilinolein, waxes C36, unsaturated volatile C6 aldehydes (trans-2-hexenal most markedly), and the same prominent sterols and superior alcohols found in SCO. In MCO, which also contained a proportion of unknown plant oil, several components showed magnitudes that were lower compared to SCO but higher with respect to VOO. The last had the aliphatic and triterpene alcohol concentration higher compared to that of both SCO and MCO. Several chemometric methods, applied to different analytical data sets, proved to be effective in grouping the three oil kinds.  相似文献   
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ABSTRACT

This work aimed at increasing the content of calcium and the quality of fatty acid composition of food mixtures developed with by-products from Nile tilapia fed with flaxseed. Mixes using cassava flour and by-products were submitted to analyses of proximate composition, fatty acids and minerals quantification, and sensory assessment. The lipid and protein fractions were higher for the mix containing 30% addition of fish meal. There was an incorporation effect of essential fatty acids in the mix of flours containing fish fed with flaxseed. Calcium had the highest concentration among minerals. Sensory acceptance range was 55–65% for formulations with fish by-products.  相似文献   
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