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51.
The future of radiography will be digital. In exotic pet radiography, where some of the animals have a very low body weight and anatomic structures can be small, detail rendition plays an important feature in image quality. Veterinarians should be familiar with the technical principles, image quality criteria, and radiation exposure issues associated with the various types of digital systems currently available. This article discusses basic principles of digital radiography, technical solutions, and selected parameters characterizing detectors, processing, and monitors. An overview of reported experiences is given, and results from experimental clinical studies are reviewed to evaluate the current options and limitations in applying digital radiography to exotic pet medicine.  相似文献   
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The potential acidity associated with dews,frosts, and fogs   总被引:1,自引:0,他引:1  
Acidity associated with special meteorological events such as dews, frosts, and fogs may cause significant environmental effects ranging from increased leaching of plant metabolites to material corrosion. In addition, dews, frosts and fogs occur with much greater frequencies than rain or snow in most areas. Due to these facts, a theoretical study was conducted to determine the potential acidity associated with these events. Results from this study showed the potential acidity associated with these events to be significant. Values of fog pH are extremely sparse, but indicate that they are slightly acidic. However, these experiments have probably under-estimated the actual acidic potential of dew and frost. Theoretical calculations indicate that synergistic acidity from dew or frost in combination with dry deposition may result in very strong localized acidities.  相似文献   
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This study was conducted in 36 indoor 40‐L fibreglass aquaria to determine the weight gain and survival of Litopenaeus vannamei fed different dietary levels of fish (FM) and squid meal (SM) and to evaluate the potential of phytoplankton to reduce FM and SM levels in shrimp feeds. Six experimental isonitrogenous (35% protein) and isocaloric (17.5 kJ g?1) diets were formulated to contain either 5%, 10% or 20% SM combined with either 6.5% or 12% FM. Dietary effects on growth and survival were compared in two systems: a ‘CLEAR water system’ (CWS) without the presence of microalgae and a ‘GREEN water system’ (GWS) with microalgae in the culture water. Shrimp cultured in the GWS had 28–57% greater weight gain than those cultured in the CWS, regardless of dietary treatment. However, survival was not different. Shrimp cultured in the CWS or the GWS, and fed diets containing combinations of FM and SM did not show differences in weight gain and feed conversion ratio. These results suggest that under the conditions existing during this research, 6.5% FM and 5% SM can be used as a cost‐effective combination in commercial feeds for shrimp production and that growth can be enhanced in the presence of primary productivity.  相似文献   
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A flea larval bioassay was developed by an international team of scientists to monitor the susceptibility of fleas (Ctenocephalides felis) to imidacloprid (Advantage, Bayer HealthCare). The assay was validated using laboratory and field isolates of C. felis. Flea eggs representing different field isolates of C. felis were collected by veterinarians in the United States, United Kingdom, and Germany. Of the 972 flea isolates obtained during the 5-year study, 768 contained sufficient numbers of eggs to conduct the larval bioassay. Greater than 5% survival occurred for only six of the field isolates evaluated. Further evaluation and analysis of these isolates demonstrated that they did not differ significantly in their susceptibility to imidacloprid from the reference strains used to develop the assay. Collections of field flea isolates will continue in an attempt to detect and document any change in the susceptibility of field flea populations to imidacloprid.  相似文献   
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Loss of pigs during or after transport is a welfare concern, but also an economic concern for producers. Transport losses include animals that are dead on arrival (DOA) at the plant, pigs that are injured, and pigs which are not obviously injured but unwilling or unable to walk (non-ambulatory, non-injured or NANI). The objective of this research was to assess the health of non-ambulatory, non-injured (NANI) pigs relative to control pigs at the processing plant by looking at a range of measures, including complete blood chemistry, anatomy, and pathology to determine potential factors associated with pigs going down. Data were collected from NANI and control pigs at five plants in the midwest USA. Feet and legs and internal organs were inspected and the severity of the pathology scored. Alveolar macrophages were collected and counted. Blood was collected for analysis of hematology, blood chemistry and cortisol concentrations. Titers to common porcine respiratory viruses were measured in pigs from one plant. Hoof and pad problems did not differ overall between control and NANI pigs, however the percentage of severe foot problems was greater (P < 0.05) in NANI compared with control pigs at plants A and E. The percentage of total ulcers, rhinitis, and empty stomachs differed (P < 0.05) between control and NANI pigs at individual plants, but not overall. Blood hematology and chemistry differed (P < 0.05) between NANI and control pigs. Cortisol concentrations did not differ between NANI and control pigs. Titers to swine influenza virus (SIV) H1N1 and H3N2 and porcine circovirus (PCV) were lower (P < 0.01) among NANI compared with control pigs. However, more (P < 0.01) NANI pigs were positive for SIV H1N1 and H3N2 compared with control pigs. Blood hematology, chemistry, and pathology indicate a large difference between NANI and controls pigs. No single health problem was higher among NANI pigs compared to plant-matched control pigs. Rather, several problems appear to contribute to pigs becoming NANI which may differ from one plant too another.  相似文献   
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OBJECTIVE: To determine whether atropine altered the degree of mucosal eversion during jejunal resection and anastomosis in the dog. STUDY DESIGN: Part I: Prospective, blinded, randomized, controlled study using a therapeutic dose (0.04 mg/kg systemic) of atropine. Part II: Prospective, unblinded, assigned, controlled study using a pharmacologic (0.04 mg/kg local arterial) dose of atropine. ANIMALS: Part I: Twenty-two young adult female Beagle dogs used during a nonsurvival third-year veterinary student surgical laboratory (small intestinal resection and anastomosis). Part II: Ten young adult female Beagle dogs used immediately after completion of a nonsurvival third-year veterinary student orthopedic surgical laboratory. METHODS: Part I: Dogs were randomly assigned to receive either atropine (0.04 mg/kg), or an equal volume of saline, given intramuscularly (premedication) and again intravenously prior to intestinal resection. Part II: In each dog, atropine (0.04 mg/kg)/saline was alternately given in the proximal/distal jejunum. RESULTS: Part I: There was no clinically or statistically significant difference between systemic atropine and saline solution on the degree of jejunal mucosal eversion after resection. Part II: There was a statistically significant decrease in jejunal mucosal eversion with atropine compared with saline solution when injected into a local jejunal artery. CONCLUSION: Systemic atropine (0.04 mg/kg) does not alter the degree of jejunal mucosal eversion during resection and anastomosis. Jejunal intraarterial atropine (0.04 mg/kg) reduced jejunal mucosal eversion during resection and anastomosis. CLINICAL RELEVANCE: The clinical usefulness and consequences of jejunal arterial atropine administration to reduce mucosal eversion remain to be determined.  相似文献   
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OBJECTIVE: To compare temperature readings from an implantable percutaneous thermal sensing microchip with temperature readings from a digital rectal thermometer, to identify factors that affect microchip readings, and to estimate the sensitivity and specificity of the microchip for fever detection. DESIGN: Prospective study. ANIMALS: 52 Welsh pony foals that were 6 to 10 months old and 30 Quarter Horses that were 2 years old. PROCEDURES: Data were collected in summer, winter, and fall in groups 1 (n = 23 ponies), 2 (29 ponies), and 3 (30 Quarter Horses), respectively. Temperature readings from a digital rectal thermometer and a percutaneous thermal sensing microchip as well as ambient temperature were recorded daily for 17, 23, and 19 days in groups 1 through 3, respectively. Effects of ambient temperature and rectal temperature on thermal sensor readings were estimated. Sensitivity and specificity of the thermal sensor for detection of fever (rectal temperature, >or= 38.9 degrees C [102 degrees F]) were estimated separately for data collection at ambient temperatures 15.6 degrees C. RESULTS: Mean ambient temperatures were 29.0 degrees C (84.2 degrees F), -2.7 degrees C (27.1 degrees F), and 10.4 degrees C (50.8 degrees F) for groups 1 through 3, respectively. Thermal sensor readings varied with ambient temperature and rectal temperature. Rectal temperatures ranged from 36.2 degrees to 41.7 degrees C (97.2 degrees to 107 degrees F), whereas thermal sensor temperature readings ranged from 23.9 degrees (75 degrees F) to 42.2 degrees C (75 degrees to 108 degrees F). Sensitivity for fever detection was 87.4%, 53.3%, and 58.3% in groups 1 to 3, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: The thermal sensor appeared to have potential use for initial screening of body temperature in equids at ambient temperatures > 15.6 degrees C.  相似文献   
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