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61.
Sixteen sampling alternatives were examined for their performance to quantify selected attributes of overstory conifers in riparian areas of western Oregon. Each alternative was examined at eight headwater forest locations based on a 0.52 ha square stem maps. The alternatives were evaluated for selected stand attributes (trees per hectare, basal area per hectare and height to diameter ratio), using root mean square error, absolute percent bias, and mean absolute deviation as criteria. In general, rectangular strip designs outperformed fixed area circular or radial plots and variable area plots. Sampling 3.6 m wide strips perpendicular to the stream outperformed all other alternatives.  相似文献   
62.
To establish the prevalence, patterns and risk factors of animal-related injuries among veterinarians, self-administered questionnaires were given to 60 veterinarians practicing in metropolitan Kampala. The prevalence of animal-related injuries in metropolitan Kampala was 72% (95%CI, 57~84). Some veterinarians (34%) suffered multiple injuries with a mean and median of 2.1 and 2.0 injuries per veterinarian, respectively. Of a total of 70 self-reported animal related injuries, cattle accounted for 72%, cats for 25%, dogs for 23%, self inoculation for 15% and birds for 13%. Injuries associated with poultry did not require hospital treatment. The upper limb was the most the frequently (68%) injured anatomical body part of veterinarians, and vaccination of animals (25%) was the major activity associated with injury. Animal-related injuries are common among practicing veterinarians in metropolitan Kampala; however, they did not differ significantly based on the veterinarian''s gender, experience or risk awareness.  相似文献   
63.
Ectopic ureter is the most common cause of congenital urinary incontinence in the dog and cat. The occurrence of ectopic ureter in the dog has been estimated to be 0.016%. A 6-month-old ferret was evaluated for urinary incontinence and urine scalding around the perineal and inguinal areas. Ultrasonography showed a nondistended urinary bladder that contained a possible intraluminal blood clot. Excretory urography revealed a left ectopic ureter. The ferret was initially treated with oral amoxicillin-clavulanate and topical silver sulfadiazine ointment for the perineal and inguinal dermatitis associated with the incontinence. Because of the potential for complications and additional surgery with ureteral transplantation, a left nephroureterectomy was performed. Surgical recovery was uneventful and the incontinence improved, although a small amount of incontinence-associated dermatitis was still present 24 days after discharge. Phenylpropanolamine therapy was initiated to address a suspected dysfunction of the urethral sphincter. Urinary incontinence improved with the phenylpropanolamine therapy; however, a small amount of incontinence persisted throughout the 3 months in which the ferret was evaluated. To the authors' knowledge, this is the first report of an ectopic ureter in a domestic ferret.  相似文献   
64.
65.
Endoscopic tracheal lavage cytology was evaluated before and 24 hours after standing transendoscopic laser surgery of the upper airway in 18 horses (9 patients undergoing Neodymium:yttrium aluminum garnet [Nd:YAG] surgery and 9 non-patient horses undergoing argon surgery). Paired endoscopic tracheal lavages taken 24 hours apart were evaluated in six control horses to determine if the lavage technique influenced the cytology. After 24 hours, no inflammation was noted in three, mild inflammation was noted in six and suppurative inflammation in four surgically treated horses. Five of the surgically treated horses underwent general anesthesia prior to baseline tracheal lavage and had evidence of inflammation in pre-laser lavage samples; this made it difficult to assess the true incidence of laser-induced inflammation in horses in this report. Five of six control horses had a normal tracheal lavage at 24 hours. Six normal adult horses had baseline tracheal mucous clearance rates determined using scintigraphy followed one week later by tracheal mucous clearance rates two hours after either standing transendoscopic Nd:YAG ventriculectomy or standing transendoscopic argon cauterization of a 2 × 2 cm area of dorsal pharynx. The horses were left in pasture for three weeks, followed by a second baseline and post-laser tracheal mucous clearance rate using the opposite laser technique. There was no significant difference between the first and second baseline measurements. The order of laser treatments had no effect on the results obtained. There was no significant difference between the baseline tracheal mucous clearance rates (mean 1.65 ± 0.65 cm/min) and tracheal mucous clearance rates post-laser surgery (mean 1.62 ± 1.21 cm/min). Neither laser technique altered tracheal mucous clearance rates significantly (argon mean 1.57 ± 0.59 cm/min and Nd:YAG mean 1.67 ± .68 cm/min.  相似文献   
66.
Veterinarians in the United States and abroad are faced with growing public concern for the welfare of animals, particularly those in production. To prepare veterinarians to exert the leadership expected by the public and industry, steps should be taken to provide instruction in animal welfare at veterinary colleges. The ultimate goal is to offer courses in animal welfare in a consistent manner on a global scale, utilizing existing expertise in an efficient and cost-effective manner. Given the intense curricula of veterinary schools and the scarcity of instructors trained in animal welfare, a nontraditional approach is needed to educate veterinary students in the United States and abroad in animal welfare. Michigan State University (MSU) is developing a graduate-level, online interactive course in animal welfare assessment. The course will approach the topic of animal welfare education from a holistic, multidisciplinary standpoint (encompassing ethics, economics, and behavior) and address issues important to the general public and the international community. The MSU course will draw on renowned international animal welfare experts, allowing students to receive high-quality education that would be difficult in any other circumstance. The course will bridge an important gap in the veterinary curriculum and offer a complete and congruous education in animal welfare to veterinarians worldwide. The MSU course will also serve as a model for collaboration in content assembly and course delivery, by using technology to leverage global expertise in the interests of educational equity. In addition to innovative technology, such as the use of Web-collaboration software to create the course, a variety of media that enable students to interact with the material will also be incorporated throughout the course. Thus, the course will not only utilize the Internet to provide access to high-quality material, but will also require the active participation of the student, which is needed for effective learning.  相似文献   
67.
68.
Nestmate recognition in ants is based on cuticular hydrocarbons (CHCs), which are heritable and may also be acquired from the environment (i.e. diet and nest environment). In Argentine ants (Linepithema humile), diet and a homogenous environment have been shown to affect nestmate recognition by altering the CHC profile and consequently intraspecific aggression. In our study, Argentine ants were collected from field nests representing two supercolonies in South Africa. Individuals were paired in aggression assays and their CHC profiles analysed. The same nests used in the aggression assays were maintained in the laboratory for five months on a shared diet of crickets and sugar water, in soil-free nests. We predicted that aggression between previously aggressive paired individuals from different nests would decrease over time through the homogenisation of CHCs as a consequence of the shared diet and similar nesting environment. Our data showed that ants maintained in the laboratory readily absorbed prey-derived hydrocarbons and experienced a loss in the number of cuticular compounds compared with their original CHC profiles. However, the changes in CHCs did not impair nestmate recognition with non-aggressive paired interactions maintained while previously aggressive paired interactions persisted. The persistence of aggression between previously aggressive pairs despite environmental homogeneity supports the notion that intrinsic nestmate recognition cues are not overridden by extrinsic cues in the recognition system of Argentine ants.  相似文献   
69.
Histoplasmosis is one of the most common systemic fungal diseases in cats from the United States. It commonly causes respiratory or disseminated disease and is often associated with one or more cytopenias. Here, we describe 32 cats in which a Histoplasma‐like fungal infection was associated with concurrent hemophagia in at least one sample site, commonly spleen, bone marrow, liver, and/or lymph node. The degree of hemophagia was characterized as moderate or marked in the majority of cases, and in all cases, there was a predominance of phagocytized mature erythrocytes. A few cases also had macrophages with phagocytized erythroid precursors, platelets, and/or neutrophils. Complete blood count results were available for 25 cats, and cytopenias were common (20/25), including solitary anemia (10), anemia and thrombocytopenia (5), solitary neutropenia (2), pancytopenia (2), and anemia and neutropenia (1). Bone marrow samples were only available in a small subset of cases, preventing the further assessment of the causes of the cytopenias. Hemophagocytosis has been previously reported in cats with neoplastic diseases and a cat with calicivirus infection, and likely occurs with other conditions as well, such as hemorrhage or hemolysis. Results of this report suggest that systemic fungal disease is an additional differential to consider when there is hemophagia in a feline cytology sample.  相似文献   
70.
Objective of this study was to demonstrate the ubiquitous presence of glucose in urine of euglycemic cats by a highly sensitive glucose assay. The local electronic database was searched for results of quantitative urine glucose measurements in cats. A total of 325 feline urine glucose measurements were identified, of which 303 (93%) had been submitted by one of the co‐authors working in a near‐by small animal practice. After the exclusion of patients with kidney disease (n = 60), hyperthyroidism (n = 15), diabetes mellitus (n = 11), multiple diseases (n = 9) or steroid treatment (n = 3), as well as serial measurements (n = 87) and outliers (n = 8), the final study population consisted of 132 cats. Urine creatinine concentration was unavailable in five patients. Whereas all but one cat had glucose concentrations above the detection limit of the assay (0.11 mmol/L, Gluco‐quant Enzyme Kit/Roche Diagnostics), no positive glucose dipstick test result (Combur 9‐Test, Roche Diagnostics) was observed. The median (range) of urinary glucose concentration and the glucose‐to‐creatinine ratio (UGCR) was 0.389 (<0.11–1.665) mmol/L and 0.0258 (0.007–0.517) respectively. The UGCR was not affected by age, gender, breed or leukocyturia, whereas cats with hematuria had slightly higher values. Data show that so‐called “basal glucosuria” is present in the majority of cats and by no means diagnostic for diabetes mellitus or renal glucosuria. This has to be considered when using bio‐analytical methods with a low limit of quantification.  相似文献   
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