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Over the past decade, there has been an increase in the development and/or in the improvement of emerging reproductive technologies in pigs. Among emerging reproductive technologies with potential short-term application in pig production are: artificial insemination with low number of spermatozoa, cryopreservation of spermatozoa and embryos, sperm sexing, and non-surgical embryo transfer. The following review will give emphasis to recent advancements in these reproductive technologies that are starting to show possibilities of serious applications under field conditions.  相似文献   
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OBJECTIVE: To characterize attitudes toward and perceptions of free-roaming cats among individuals living in Ohio. DESIGN: Cross-sectional study. SAMPLE POPULATION: Households in Ohio. PROCEDURES: A random-digit-dial telephone survey was performed, and 1,250 households were contacted. RESULTS: 703 of the 1,250 (56.2%) households completed interviews. Five hundred fifty-three (78.7%) participants reported seeing free-roaming cats at least occasionally, and 184 (26.2%) reported having fed free-roaming cats during the previous year. However, only 42 (22.8%) participants who fed free-roaming cats had ever taken one to a veterinarian, and 43 (23.4%) participants who fed free-roaming cats reported that at least one of the free-roaming cats had produced a litter in the preceding year. Differences existed between cat owners and other participants and among urban, suburban, and rural residents in regard to their attitudes toward free-roaming cats and the need for government regulations. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that free-roaming cats were common in Ohio, but that attitudes toward and perceptions of free-roaming cats differed between cat owners and other participants and among participants grouped on the basis of residential area. Thus, developing statewide approaches for regulating free-roaming cats may be challenging or unrealistic.  相似文献   
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The objective of this study was to describe a new technique for urinary catheterisation of female dogs using a novel catheterisation device (NCD) and to compare the time taken to place a catheter using this technique with traditional techniques. A secondary objective was to survey participants on which of the techniques they preferred. Female canine cadavers of varying sizes were utilised and veterinary students who had not previously placed a urinary catheter were enrolled. Each participant performed three catheterisation techniques, Visual with speculum (SPEC), Blind Palpation (BP) and catheterisation with NCD on three sizes of dog. Time required using each technique was compared using Kaplan–Meier plots and mixed models Cox Proportional Hazards regression. Median times to catheterisation were 300 s (IQR 261–417 s) with the SPEC method, 420 s (IQR 253–545 s) with the NCD method and 725 s (574–1032s) with the BP method. Both SPEC and NCD methods were significantly faster compared to the BP method, with Hazard Ratios of 3.66 (95% CI 1.94–6.91, P < 0.001) and 3.57 (95% CI 1.87–6.81, P < 0.001), respectively. Six of nine participants found the NCD the easiest technique, 5/9 of the participants found the palpation technique most difficult and 4/9 found the speculum technique most difficult. BP appears to be the technique of least preference and increased time requirement. The novel urinary catheterisation device may provide a simpler method of visualisation of the urethral papilla and may provide a more sterile way of placing the catheter, although further investigation is needed to confirm this.  相似文献   
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The sources of variability in variability of scintigraphic measurements of glomerular filtration rate (GFR) have not been determined. The day to day variability of GFR was studied in 18 healthy beagle dogs. The renal uptake of 99mTc-diethylenetriaminepentaacetic acid (DTPA) of each dog was measured using a scintigraphic technique three times at intervals of 5-26 days. GFR was calculated from a regression equation relating uptake to plasma clearance, derived in our laboratory. The mean GFR was 3.97 +/- 0.72 (SD) ml/min/kg with values from 2.66 to 5.67 ml/min/kg. Analysis of variance (ANOVA) using a linear mixed model showed that most variability is a result of the dogs, less because of day to day variability and very little to the measurement variability. The repeatability coefficients for the day to day variability and measurement variability were 1.06 and 0.21 ml/min/kg respectively. The day to day variability can be caused by physiological homeostatic adjustments by the kidneys needed because of fluctuations in food and fluid intake, each dog's individual capacity to adjust, and to intrinsic errors in the measurement method. These results should be considered when using the scintigraphic method for clinical evaluation and research.  相似文献   
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Unlike annual crops where reclamation leaching of salts can be readily conducted between cropping, leaching of salts in permanent crops that are drip irrigated pose challenges. A need exists to formulate and test a management-type of salinity model for drip irrigation of table grapes. The model reported herein predicts the distribution of salts along the vine row and between the rows during the growing season, as affected by reactivity of salts of the applied irrigation water as well as rate and duration of drip application. The calibrated model reproduced the initial field salinity profiles after repeated irrigation cycles by adjusting only the routing factor α which is the ratio of horizontal to vertical water flow. After eight cycles the profiles stabilized and the calibrated horizontal to vertical flow routing ratio was 0.6. There is remarkable agreement between measured and simulated salinity. Corresponding soil moisture profiles show the expected high water content with depth at the emitter, the decrease in surface water content with radial distance and the increase with depth, at the distal end of the wedge. Although the model is location specific it can be applied knowing soil, initial and boundary conditions, as well as irrigation application quantity and quality and as such can be applied location by location in order to assess flow and quality of deep percolation recharging the groundwater system. With this capacity the model can predict soil water quantity and quality outcomes for possible land and water management scenarios.  相似文献   
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