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Andrea M. DeLuke Dave A. Allen Eric R. Wilson Jayce A. Lineberger Terry W. Lehenbauer Michelle Fabiani Brian A. Poteet 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(10):1095-1099
Radiographic osteoarthritis scores were determined in 60 dogs up to 3 years following tibial plateau leveling osteotomy. Radiographs taken immediately following surgery and at long-term follow-up 1 to 3 years later were evaluated by 2 certified radiologists using a modified 32-point osteoarthritis scale. Changes in osteoarthritis scores were evaluated by paired t-tests and regression analysis. Sub-groups of dogs were formed to evaluate if osteoarthritis scores changed differently for follow-up periods of < 24 months compared with those > 24 months. There was a significant increase in osteoarthritis score from post-operative to follow-up evaluations for all dogs studied. Regression analysis of the relationship of months after surgery to change in osteoarthritis score was not significant. These results indicate that osteoarthritis did progress following tibial plateau leveling osteotomy, but not in a linear fashion over time. 相似文献
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Rees EE Merrill EH Bollinger TK Hwang YT Pybus MJ Coltman DW 《Preventive veterinary medicine》2012,104(1-2):149-159
Chronic wasting disease (CWD) is a fatal disease of North American cervids that was first detected in a wild, hunter-shot deer in Saskatchewan along the border with Alberta in Canada in 2000. Spatially explicit models for assessing factors affecting disease detection are needed to guide surveillance and control programs. Spatio-temporal patterns in CWD prevalence can be complicated by variation in individual infection probability and sampling biases. We assessed hunter harvest data of mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus) during the early phases of an outbreak in Saskatchewan (i.e., 2002-2007) for targeting the detection of CWD by defining (1) where to look, and (2) how much effort to use. First, we accounted for known demographic heterogeneities in infection to model the probability, P(E), that a harvested deer was infected with CWD given characteristics of the harvest location. Second, in areas where infected deer were harvested we modelled the probability, P(D), of the hunter harvest re-detecting CWD within sample units of varying size (9-54 km(2)) given the demographics of harvested deer and time since first detection in the study area. Heterogeneities in host infection were consistent with those reported elsewhere: mule deer 3.7 times >white-tailed deer, males 1.8 times>females, and quadratically related to age in both sexes. P(E) increased with number of years since the first detection in our study area (2002) and proximity to known disease sources, and also varied with distance to the South Saskatchewan River and small creek drainages, terrain ruggedness, and extent of agriculture lands within a 3 km radius of the harvest. The majority (75%) of new CWD-positive deer from our sample were found within 20 km of infected deer harvested in the previous year, while approximately 10% were greater than 40 km. P(D) modelled at 18 km(2) was best supported, but for all scales, P(D) depended on the number of harvested deer and time since the first infected deer was harvested. Within an 18 km(2) sampling unit, there was an 80% probability of detecting a CWD-positive deer with 16 harvested deer five years after the initial infected harvest. Identifying where and how much to sample to detect CWD can improve targeted surveillance programs early in the outbreak of the disease when based on hunter harvest. 相似文献
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The purpose of this study was to determine whether the strength properties of a composite board containing waste paper as a core material, could be improved by the prior prepressing of the core material before pressing the product to final thickness. Results indicated that intermediate cold prepressing of the core layer had no effect on the bending strength and MOE and can thus be eliminated. Flakeboard containing Kraft waste paper appears to be superior to commercial particle boards, with regard to thickness swelling in water. Results so far obtained indicate that waste paper can be utilized for flakeboard manufacture. 相似文献
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Dave O. Jirsa Kevin R. Stuart Guillaume P. Salze Melanie A. Rhodes D. Allen Davis Mark A. Drawbridge 《Journal of the World Aquaculture Society》2014,45(6):681-690
Three trials were run to identify the limiting dietary amino acids in practical, soy‐based formulations for California yellowtail juveniles. In the first trial, four diets were formulated with 20% fish meal and 43% soy protein concentrate. The basal diet was supplemented with methionine, lysine, and taurine (MLT), and each supplement was then individually deleted in three additional diets (LT, MT, and ML). A significant decrease in growth was only seen in fish fed the ML diet. The second and third trials were designed to test graded levels of dietary taurine and methionine, respectively. Dietary taurine ranged from 0.32 to 1.5%, and methionine levels ranged from 0.95 to 1.19% of the diet with constant levels of cysteine (0.73%). While weight gains were considered adequate to detect a dietary amino acid deficiency, there was no significant effect of graded levels of either taurine or methionine on final weights, growth rates, survival, or feed efficiency. In conclusion, the practical diets tested required taurine supplementations, but did not require lysine or methionine supplementation. While these data are insufficient to determine the taurine or methionine requirement of California yellowtail, it provides minimum levels likely to meet these requirements. Additional research is necessary to determine taurine and methionine requirements precisely in this species. 相似文献
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Guillaume P. Salze Kevin R. Stuart Dave O. Jirsa D. Allen Davis Mark A. Drawbridge 《Journal of the World Aquaculture Society》2018,49(1):113-126
Although taurine has been identified as a required nutrient in several Seriola species, there are no available quantitative data on dietary taurine requirements for these commercially important species and recommendations are highly variable. Therefore, juvenile Seriola lalandi were fed one of eight practical diets supplemented with graded levels of taurine (0.11–1.08% of the dry diet, analyzed) to estimate their taurine requirement. Response in growth rate, feed efficiency, and nutrient deposition were evaluated using a broken‐quadratic model and 4‐ and 5‐parameter saturation kinetic models (4‐SKM and 5‐SKM) Blood serum composition was analyzed using linear models. Requirement estimates based on growth rates (thermal‐unit growth coefficient) and protein deposition were similar at 0.26% (95% confidence interval [CI]: 0.23–0.28) and 0.29% (95% CI: 0.25–0.34) dietary taurine, respectively. Feed and protein deposition efficiencies were optimized at 0.26–1.02% and 0.26–1.00% dietary taurine, respectively. Taurine deposition in the animal was maximized at higher dietary levels (0.64%). Levels of serum taurine increased in response to dietary levels and peaked at around 0.80% dietary taurine. Concomitantly, serum urea and total amino acid levels decreased with increasing dietary taurine levels, suggesting a reduced amino acid catabolism relative to the aforementioned improvement in protein deposition efficiency. 相似文献
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