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The accepted paradigm of foreign animal disease preparedness in Canada, the emergency for which to prepare, starts with identification of the exotic viral agent in a Canadian farm animal population. This narrative focuses on the containment of the infectious agent, within diseased animals, on infected premises. Framing the emergency as a disease incursion limits rational imagination to only one version of one potential animal emergency. This framing of the problem directs the carcass disposal solutions to consider only methods to dispose of viral infected material. However, in all documented responses to catastrophic swine diseases in the past three decades, the number of uninfected animals caught up in movement control zones and killed greatly exceeds the number of infected animals killed. The temporary closures of slaughterhouses in spring 2020 due to COVID-19 transmission resulted in thousands of healthy market hogs surplus to market; an unanticipated emergency of healthy pigs. This paper proposes an alternate carcass disposal option for material from uninfected farms. “Excarnation by exposure” is a natural process of debulking and dehydrating carcasses by blow fly larvae, mitigating financial costs of final disposal. Excarnation by exposure is a reasonable and possibly necessary additional option for the management of uninfected carcasses in a catastrophic emergency response in commercial pigs. 相似文献
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Hermer JV Bush MA Whiting C Langley-Hobbs SJ 《Veterinary and comparative orthopaedics and traumatology》2012,25(2):155-159
Two kittens aged between four and five months were presented having sustained patellar fractures. In both cases, healing was subsequently documented radiographically; this has not been reported previously in the literature. One kitten had bilateral patellar fractures - the symptomatic right stifle was treated with a pin and tension-band-wire which later failed, at which point partial patellectomy was performed. The fracture of the left patella was minimally displaced and was treated conservatively. A radiograph of the left patella taken eleven months after initial presentation showed complete healing of the fracture. The second case was treated surgically with a circumferential wire; healing of the fracture was demonstrated radiographically at twelve weeks postoperatively. Radiographic images taken five weeks postoperatively had shown some narrowing of the fracture gap. These two cases demonstrate that bony union of patellar fractures can be documented, given a long enough duration of radiographic follow-up; circumferential wire was an effective treatment in a displaced fracture, and conservative treatment resulted in complete healing of a minimally displaced fracture. 相似文献
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Terry L. Whiting Rosemary C. Postey Seylene T. Chestley Gustave C. Wruck 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(11):1173-1180
Cattle death by starvation is a persistent annual event in Manitoba. Herds with more than 10% overwinter death loss are usually identified in the late winter or early spring. Field and postmortem findings suggest that there is complete mobilization of fat followed by inability to maintain adequate thermoregulation and death by cardiac arrest. Carcasses show only mild evidence of muscle catabolism and are in excellent preservation if located prior to or around the time of spring thaw. A forensic diagnosis of death by starvation-induced exposure can be made with a high level of confidence when considering field data, whole carcass appearance, and postmortem evaluation of residual fat stores. 相似文献
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Donald F. Charles Donald R. Whitehead Dennis S. Anderson Raymond Bienert Keith E. Camburn Robert B. Cook Thomas L. Crisman Ronald B. Davis Jesse Ford Brian D. Fry Ronald A. Hites Jeffrey S. Kahl John C. Kingston Russell G. Kreis Jr. Myron J. Mitchell Stephen A. Norton Linda A. Roll John P. Smol P. Roger Sweets Allen J. Uutala Jeffrey R. White Mark C. Whiting Robert J. Wise 《Water, air, and soil pollution》1986,30(1-2):355-365
The PIRLA project is an interdisciplinary paleoecological study designed to provide reconstructions of the recent acidification histories of a representative set of lakes in four acid-sensitive regions in North America. We are trying to determine if lakes in the study regions have acidified, and if so, to what extent, over what time period and why. Sediment cores from 5 to 15 lakes in each region are being analyzed for several characteristics. Diatoms and chrysophytes are being used to reconstruct lakewater pH. Results for three Adirondack lakes with current pH of 4.8 to 5.0 indicate a decrease in pH beginning in the 1930's–1950's. Increased atmospheric deposition of strong acids appears to be the primary factor responsible for the pH decline. Two lakes (pH 4.4 and 4.7) in New England show clear evidence of acidification probably due to acidic deposition. Preliminary reconstructions for two lakes in Michigan (pH 4.4 and 5.6), one in Wisconsin (pH 5.3), and one in Minnesota (pH 6.8) suggest no recent pH decrease. For, the one Florida lake (pH 4.4) analyzed, inferred pH decreases by about 0.5 unit, beginning in the 1950s; the cause has not been determined. 相似文献