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1.
本文利用链烷烃技术对驼羊放牧采食选择性进行了研究.研究表明驼羊喜食禾本科牧草,且在日粮中的采食比例最大,平均达70%以上,其次为鼠尾草科,平均达10%以上.另外,研究还表明驼羊对其它牧草的采食程度也不一样.  相似文献   
2.
The aim of this study was to validate an automated immunoturbidimetric assay used to quantify human albumin in urine and to accurately measure canine albumin concentrations in both urine and cerebrospinal fluid. The partial homology existing between human and canine albumin limited the accuracy of the human assays in measuring canine albumin without method modifications. Thus, the assay was modified by calibrating the analyzer with calibrators made in the laboratory containing known concentrations of canine albumin. To prepare the set of calibrators, the albumin concentration of pooled sera of healthy dogs was assessed in 5 replicates using the BromocresolGreen assay. Pooled samples were aliquoted and serially diluted to obtain the expected concentrations of albumin (0.5, 1, 5, 13, and 30 mg/dl) for establishing the canine calibration curve. Thereafter, the performance was assessed by analyzing canine urine and CSF The modified assay accurately quantified canine albumin in both specimens, as indicated by the following. Intra- and interassay variability was 0.92% and 2.74%, respectively; recovery was 99.66% and 99.07% in urine and 105.02% in CSF No interference was detected when hemolysate and glucose were added to urine. The test was linear within the verified range (0-225 mg/dl). These results demonstrate that the modified human albumin immunoturbidimetric assay can be a useful tool in the veterinary diagnostic laboratory. It is accurate and tends itself to automatization on chemistry analyzers.  相似文献   
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4.
Thymoma is a relatively common tumor in rabbits. Treatment with surgery, radiation therapy, and chemotherapy alone or in combination has been reported with varying outcomes. Stereotactic volumetric modulated arc radiotherapy delivered in a hypofractionated manner allows high doses of radiation to be delivered to the target volume while allowing sparing of adjacent critical structures. This therapy is ideally suited for thymomas in rabbits given their size, the difficulty of multiple anesthesia episodes and the complexity of the radiotherapy plans required due to the tumor's proximity to the heart, lungs, and mediastinal structures. Fifteen rabbits with thymoma were prospectively recruited for this observational, single institution, single arm clinical study. All rabbits were imaged with both computed tomography (CT) and magnetic resonance imaging (MRI). A total dose of 40 Gy in six fractions was delivered using a single arc over an 11‐day period with repeat CT simulation done every other fraction for adaptive planning. Follow‐up evaluation was done through repeat CT and MRI imaging and revealed complete responses using the Response Evaluation Criteria in Solid Tumors (RECIST) criteria. Two rabbits had died at 618 and 718 days, 10 were alive and three were lost to follow‐up. Observed acute and late effects were graded according to the Veterinary Radiation Therapy Oncology Group (VRTOG) criteria and were found to be minimal.  相似文献   
5.
A bilateral and symmetrical neuronal vacuolation associated with spinal cord white matter degeneration and laryngeal neuropathy was observed in a 12-week-old male mixed-breed dog with a history of progressive pelvic limbs ataxia. On clinical examination, signs included inspiratory stridor, spinal ataxia, tetraparesis, and proprioceptive deficits more severe in the pelvic limbs. Examination of the larynx showed bilateral laryngeal paralysis and electromyography revealed fibrillation potentials restricted to the intrinsic laryngeal muscles. Clinical and pathological findings resembled the syndrome of neuronal vacuolation and spinocerebellar degeneration described in Rottweiler dogs. This is the first report of a similar disorder in a dog different from Rottweiler.  相似文献   
6.

Background

In order to improve the biological control agent (BCA) efficacy, stress factors threatening the viability of microorganisms during spray application need to be determined. The effect of spray mixture temperature and exposure time on Trichoderma harzianum T 22 and Bacillus amyloliquefaciens QST713 viability were tested. Concurrently the combined effect of mechanical and thermal stress effect on BCA viability were tested at two initial spray mixture temperatures (14 and 25 °C) by simulating a spray application using airblast sprayers featured by different tank capacity and a spray liquid circuit (without and with hydraulic agitation system). To assess the BCA microorganism viability, spray mixture samples were collected at time intervals along trials and plated to count the colony forming units (CFU).

Results

The critical temperature threshold that inhibited BCA viability was 35 °C with 30 min of exposure. The sprayer type, the initial temperature of the spray mixture and the temperature increment during the trials significantly decreased the number of CFU recovered. When simulating a spray application, the spray mixture temperature increase rate was determined mainly by the residual amount of spray mixture in the tank. Even if the tank capacity does not substantially affect the final temperature reached by the spray mixture, the higher residual spray mixture in bigger tanks can expose the BCAs for a longer time to critical temperatures.

Conclusions

Experimental trials allowed us to identify the effect of factors affecting the viability of tested BCAs, providing information about the actual chance to guarantee the biological efficacy of BCA treatments. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
7.
OBJECTIVES: To evaluate the accuracy of 2 radiographic methods used to assess tibial plateau slope (TPS) in dogs and evaluate effects of film digitization and radiographic beam placement on TPS measurements. SAMPLE POPULATION: 16 hind limbs from dog cadavers weighing > 20 kg. PROCEDURES: Radiographs of tibiae were made with the radiographic beam centered over the stifle joint and midshaft of the tibia. Tibiae were collected, the femorotibial contact area was determined, and slope of the medial tibial condyle in relation to the tibial shaft was measured. Radiographs were digitized. Slope of the medial tibial condyle was measured on printed and digitized radiographs read in random order by 6 examiners unaware of anatomic measurements. Three examiners used a conventional measuring technique, and 3 examiners used an alternative measuring technique. RESULTS: Anatomic measurements were significantly higher than radiographic measurements made by use of the conventional interpretation method but did not differ from radiographic measurements made by use of the alternate method. Measurements from printed radiographs were lower than measurements from digitized radiographs for the 4 most experienced examiners. CONCLUSIONS AND CLINICAL RELEVANCE: Measurements made by use of a line tangential to the cranial, linear portion of the medial tibial condyle at the femorotibial contact point were accurate measurements of the anatomic TPS. Measurements made by use of the conventional TPS measurement method underestimated the anatomic TPS. Measurements made on digitized radiographs were typically more accurate than measurements made on printed radiographs.  相似文献   
8.
Veterinary Research Communications - Canine parvovirus type 2 (CPV-2) is one of the most relevant pathogens associated with enteritis in dogs and is frequently reported in association with the...  相似文献   
9.
Photoinhibition of photosynthesis and photosynthetic recovery were studied in detached needles of cypress (Cupressus sempervirens L.) Clones 52 and 30 under controlled conditions of high irradiation (about 1900 micromol m(-2) s(-1) for 60 min; HL treatment), followed by 60 min in darkness. The degree of photoinhibition was determined based on the ratio of variable to maximum chlorophyll fluorescence (Fv/Fm), which is a measure of the potential efficiency of photosystem II (PSII), and on electron transport measurements. The Fv/Fm ratio declined in needles of both clones in response to the HL treatment. Minimal fluorescence (Fo) increased in HL-treated needles of both clones. The HL treatment decreased rates of whole-chain and PSII activity of isolated thylakoids more in Clone 52 than in Clone 30. In needles of both clones, PSI activity was less sensitive to photoinhibition than PSII activity. In the subsequent 60-min dark incubation, fast recovery was observed in needles of both clones, with PSII efficiencies reaching similar values to those in non-photoinhibited needles. The artificial exogenous electron donors diphenyl carbazide (DPC), hydroxylamine (NH2OH) and manganese chloride (MnCl2) failed to restore the HL-induced loss of PSII activity in needles of Clone 30, whereas DPC and NH2OH significantly restored PSII activity in photoinhibited needles of Clone 52. Quantification of the PSII reaction center protein D1 and the 33-kDa protein of the water-splitting complex following HL treatment of needles revealed pronounced differences between Clone 52 and Clone 30. The large decrease in PSII activity in HL-treated needles was caused by the marked loss of D1 protein and 33-kDa protein in Clone 30 and Clone 52, respectively.  相似文献   
10.
Carcinomas represent two‐thirds of canine nasosinal neoplasms. Although radiation therapy (RT) is the standard of care, the incidence of local recurrence following treatment is high. Cyclooxygenase‐isoform‐2 (COX‐2) is expressed in 71–95% of canine nasal carcinomas and has been implicated in tumor growth and angiogenesis. Accordingly, COX‐2 inhibition seems rational to improve outcome. Dogs with histologically confirmed, previously untreated nasal carcinomas were randomized to receive the combination of a selective COX‐2 inhibitor (firocoxib) and palliative RT (Group 1) or RT and placebo (Group 2). Patients were regularly monitored with blood tests, urinalysis, and computed tomography. Pet owners were asked to complete monthly a quality‐of‐life questionnaire. Twenty‐four dogs were prospectively enrolled. According to Adams modified system, there were five stage 1, five stage 2, three stage 3, and 11 stage 4 tumors. Two dogs had metastases to regional lymph nodes. Median progression‐free interval and overall survival were 228 and 335 days in Group 1 (n = 12) and 234 and 244 days in Group 2 (n = 12). These differences were not statistically significant. The involvement of regional lymph nodes was significantly associated with progression‐free interval and overall survival (P = 0.004). Quality of life was significantly improved in Group 1 (P = 0.008). In particular, a significant difference was observed for activity and appetite. Although not providing a significant enhancement of progression‐free interval and overall survival, firocoxib in combination with RT is safe and improved life quality in dogs with nasal carcinomas.  相似文献   
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