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181.
The black-backed woodpecker (Picoides arcticus) is a species of management concern in California. As part of a study of black-backed woodpecker home range size and foraging ecology, nine birds in Lassen National Forest (Shasta and Lassen Counties, California) were radio-tracked during the 2011 breeding season. One of the marked birds was found dead after being tracked for a 10-wk period in which it successfully nested. A postmortem examination of the dead bird revealed that it was emaciated and autolyzed, with the presumptive cause being numerous spiruroid nematodes of the genus Procyrnea in the gizzard. This first observation of Procyrnea nematodes in a black-backed woodpecker is notable because the Procyrnea infection was considered lethal and because Procyrnea has been implicated in substantial die-offs in other bird species, including woodpeckers.  相似文献   
182.
Exotic animals, including small herbivores, are increasing in popularity as companion animals. Commonly owned exotic herbivores include guinea pigs, chinchillas, and rabbits. These animals fall into the category of prey species with an inherent instinct to hide their illness until severely affected by the disease process. Therefore, any of these animals presented as an emergency case must be carefully evaluated for chronic underlying illness. Cardiovascular emergency and critical care principles are similar across all mammalian species. However, specialized techniques and adaptations are occasionally required because of the unique physiology and natural behaviors of these animals. It is essential to evaluate and stabilize these patients before attempting definitive diagnostic plans. Emergency cardiovascular presentations, as in other mammals, consist of congestive heart failure, arrhythmias, pericardial effusion, and toxicities that can result in cardiac and pulmonary arrest. Cardiac disease is a relatively common finding in small exotic mammals, but there are few peer-reviewed reports regarding diagnosis and treatment of heart disease in these species. Diagnostic testing and treatment options are generally based on knowledge of small animal medicine.  相似文献   
183.
OBJECTIVE: To evaluate postoperative complications, limb function, and tumor control after intercalary resection and reconstruction for preservation of limb and joint function in dogs with high-grade malignant tumors of diaphyseal bone. STUDY DESIGN: Retrospective study. ANIMALS: Seventeen client-owned dogs. METHODS: The bone tumor database and medical records were reviewed (1986-2002) for dogs with diaphyseal tumors treated with intercalary resection and reconstruction with either an allograft or irradiated autograft. Clinical presentation, diagnostic findings, surgical management, and outcome were determined from medical records and telephone interviews with veterinarians and owners. Statistical analyses included chi2 to test associations between intra- and postoperative variables with complications, and Kaplan-Meier survival analysis for disease-free interval, metastasis-free interval (MFI), and median survival time. RESULTS: Intercalary limb-sparing surgery was performed in 17 dogs with diaphyseal tumors: osteosarcoma (OSA) (15), histiocytic sarcoma (1), and solitary metastasis from a pulmonary adenocarcinoma (1). One dog was excluded from further analysis when the spared limb was amputated 4 days postoperatively because of incomplete tumor resection. In 16 dogs, limb function was good to excellent. Complications occurred in 5 dogs (31.3%) and included superficial infection in 2 dogs (12.5%) and implant failure in 4 dogs (25%). All implant failures occurred in the ulna and there was a significant association between implant failure and non-cemented allografts (P=.042). Non-union of 1 or both osteotomies was diagnosed in 10 dogs (83.3%) and, despite lack of clinical signs in all cases, was significantly associated with the use of intracavitary locally released cisplatin (P=.046) and cemented intercalary grafts (P=.046). Local tumor recurrence was diagnosed in 1 dog (6.3%) and metastatic disease in 12 dogs (75.0%), including 10 dogs with OSA. The median MFI was 137 days. The local disease-free and overall limb-salvage rate was 94% and 100%, respectively. Overall median survival time was 393 days and the median survival time for dogs with OSA was 449 days. CONCLUSION: Intercalary limb-sparing surgery results in better postoperative limb function with fewer and less severe complications than historical reports of dogs treated with non-intercalary limb-sparing surgery. CLINICAL RELEVANCE: In dogs with diaphyseal tumors, intercalary limb-sparing surgery preserves normal joint function and results in good to excellent limb use with few complications and good local tumor control.  相似文献   
184.
Fifteen dogs with appendicular osteosarcoma (presumptive diagnosis, n = 6 dogs; biopsy confirmed, n = 9 dogs) were treated with palliative radiotherapy. Treatment entailed a total of three 10 Gy fractions of 60Co radiation delivered over a three week period on days 0, 7 and 21, for a total dose of 30 Gy. Twelve dogs experienced improvement in limb function 7–22 days after the start of treatment. Long term followup was available for nine of the twelve responders. The duration of response was 17–288 days (n = 9 dogs; median = 130 days; mean = 116 days). Response duration did not appear to be related to initial tumor size. Palliative radiotherapy can result in improved limb function in dogs with appendicular osteosarcoma.  相似文献   
185.
Intervertebral disk extrusions into the spinal cord are rarely reported in veterinary medicine, and only necropsy findings are described in previous reports. It is hypothesized that a disk lesion results in forceful injection of disk material into the spinal cord. In the 3-year-old Miniature Doberman Pinscher of our report, acute clinical signs and results of magnetic resonance imaging were consistent with this disease and helped determine the extent and character of the lesions. Alteration in the appearance of the nucleus pulposus was important in determining that intervertebral disk disease may have been present in this dog. However, a definitive diagnosis of intramedullary disk extrusion can be made only via histologic examination of a biopsy specimen or at necropsy. The dog improved substantially after surgical decompression of the spinal cord, and histologic findings in a biopsy specimen of material found within the spinal cord were consistent with mature degenerate intervertebral disk material.  相似文献   
186.
A study of the actinosporean fauna of oligochaetes from a freshwater salmon farm in Northern Scotland was carried out from October 1996 to August 1998. Following the examination of 28,387 oligochaete worms belonging to the families Tubificidae, Lumbriculidae, Naididae and Enchytraeidae, five types of echinactinomyxon (four previously described), six types of raabeia (five previously described), three types of synactinomyxon (all previously described), four types of aurantiactinomyxon (three previously undescribed), one type of triactinomyxon (previously described), one type of neoactinomyxum (previously undescribed) and one type of siedleckiella (previously undescribed) were identified. The triactinomyxon type was released from unidentified immature oligochaetes. Of the twenty-one types of actinosporeans found, thirteen types were released from Tubifex tubifex (Müller), three types were released from Lumbriculus variegatus (Müller), three types from both L variegatus and T. tubifex and two types from immature oligochaetes.  相似文献   
187.
Three woody ornamentals were fertilized with 6 nitrogen sources, each applied at 100, 200 and 400 mg/l N. Toxicity was evident from ammoniacal sources, especially at the high rates. Nitrate sources were not injurious, except on viburnum at the highest rate. Doublefile viburnum was severely injured by all ammoniacal sources, while forsythia showed minimal injury and spreading cotoneaster none. Freezing-studies showed that all plants, whether visually affected by the ammoniacal sources or not, showed more freezing-injury than plants grown with nitrate sources. Nitrogen rate did not affect the degree of freeze injury. The impairment of metabolic processes by excess ammonium nutrition predisposed the plants to greater freeze injury.  相似文献   
188.
189.
Preferences for landscapes are critical because they can drive landscape changes over time. The mediating role of wildlife value orientations in influencing preferences for urban wetlands through the provision of ecological information (based on insectivorous bats) was experimentally tested. Residents (N = 198) were asked about their preferences for wetlands, as depicted in 27 photographs. Half of the participants were provided with ecological information. Urban wetlands of high habitat quality for bats were preferred by both groups. There was a significant influence of ecological information on preference, although unexpectedly, this was on wetlands of low quality habitat; people who received ecological information had lower preferences for wetlands that provided lower quality habitat for bats. This influence was mediated by wildlife value orientations (wildlife rights and recreational wildlife experiences). Results suggest that preferences for landscapes can be influenced by providing information that is consistent with value orientations.  相似文献   
190.
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