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A newly recognized syndrome, characterized by sudden death of farmed deer that are in good to excellent nutritional condition, with lesions of small intestinal mucosal hemorrhage and splenomegaly, is described. Other frequently observed lesions were small intestinal mucosal necrosis, abomasal hemorrhage, random hepatic necrosis, and multifocal hepatic congestion. Clostridium perfringens type A was isolated in high numbers from the intestines of many of the deer affected by the syndrome; however, the numbers were not significantly different from those of control deer. The syndrome did not appear to be related to dietary or any other specific management factors and a definitive cause of the syndrome was not identified.  相似文献   
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Hendra virus (HeV) is a zoonotic virus from the family Paramyxoviridae causing fatal disease in humans and horses. Five-week-old Landrace pigs and 5-month-old Gottingen minipigs were inoculated with approximately 107 plaque forming units per animal. In addition to fever and depression exhibited in all infected pigs, one of the two Landrace pigs developed respiratory signs at 5 days post-inoculation (dpi) and one of the Gottingen minipigs developed respiratory signs at 5 dpi and mild neurological signs at 7 dpi. Virus was detected in all infected pigs at 2–5 dpi from oral, nasal, and rectal swabs and at 3–5 dpi from ocular swabs by real-time RT-PCR targeting the HeV M gene. Virus titers in nasal swab samples were as high as 104.6 TCID50/mL. The viral RNA was mainly distributed in tissues from respiratory and lymphoid systems at an early stage of infection and the presence of virus was confirmed by virus isolation. Pathological changes and immunohistochemical staining for viral antigen were consistent with the tissue distribution of the virus. This new finding indicates that pigs are susceptible to HeV infections and could potentially play a role as an intermediate host in transmission to humans.  相似文献   
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It was hypothesized that horses exhibiting crib-biting (CB) have a greater degree of gastric mucosal damage and higher serum gastrin response to concentrate feeding than non-crib-biting (NCB) horses. Eighteen mature horses, 9 CB and 9 NCB, were used to determine prevalence and severity of gastric mucosal damage and effect of concentrate feeding on circulating gastrin. Horses were maintained on pasture with free access to hay and fed a pelleted concentrate diet twice daily. Number of crib-bites and duration of cribbing bouts were recorded in a 24-hour period. Endoscopic examinations (EE) of the squamous mucosa were performed and gastric fluid sampled after 24 to 28 hour feed removal. Following EE, horses were returned to pasture for 72 hours. Blood was collected following 12-hour feed removal (0 minutes), and at 60 and 120 minutes after consuming 1 kg of concentrate. Mean number of crib bites in 24 hours was 1,558 ± 303 with CB peaking prior to and during the afternoon feeding (3:30 PM, P < .05). There were no differences in the number or severity of ulcers, prevalence of hyperkeratosis, or baseline gastric pH between CB and NCB. Serum gastrin concentration at 60 and 120 minutes was greater (P < .05) and tended to be greater (P < .06), respectively, in CB than in NCB horses following feeding of concentrate. Crib-biting behavior in horses maintained on pasture was not associated with gastric mucosal damage; however, consumption of concentrate feed resulted in greater serum gastrin concentration in CB horses.  相似文献   
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Changing climate and fuel accumulation are increasing wildfire risks across the western United States. This has led to calls for fire management reform, including the systematic use of prescribed fire. Although use of prescribed fire by private landowners in the southern Great Plains has increased during the past 30 yr, studies have determined that liability concerns are a major reason why many landowners do not use or promote the use of prescribed fire. Generally, perceptions of prescribed fire ? related liability are based on concerns over legal repercussions for escaped fire. This paper reviews the history and current legal liability standards used in the United States for prescribed fire, it examines how perceived and acceptable risk decisions about engagement in prescribed burning and other activities differ, and it presents unanticipated outcomes in two cases of prescribed fire insurance aimed at promoting the use of prescribed fire. We demonstrate that the empirical risk of liability from escaped fires is minimal (< 1%) and that other underlying factors may be leading to landowners’ exaggerated concerns of risk of liability when applying prescribed fire. We conclude that providing liability insurance may not be the most effective approach for increasing the use of prescribed fire by private landowners. Clearly differentiating the risks of applying prescribed fire from those of catastrophic wildfire damages, changing state statutes to reduce legal liability for escaped fire, and expanding landowner membership in prescribed burn associations may be more effective alternatives for attaining this goal. Fear of liability is a major deterrent to the use of prescribed fire; however, an evaluation of the risks from escaped fire does not support perceptions that using prescribed fire as a land management tool is risky. Prescribed burning associations and agencies that support land management improvement have an important role to play in spreading this message.  相似文献   
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