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111.
Immunoreactive corticosterone and corticosterone metabolites (ICCM) were quantified in excreta of permanently single housed (n = 10) and permanently pair housed (n = 20) roosters. The pair housed roosters were separated and single housed, and ICCM were quantified in the droppings before and during 15 days after separation. There was no statistically significant difference in ICCM excretion in the droppings between the permanently single or pair housed roosters. After separation, however, the previously pair housed roosters showed a significantly transient elevated excretion of ICCM in droppings the second day after separation indicating that the separation and relocation is associated with an activation of the hypothalamic-pituitary-adrenal axis.The excretion of ICCM in droppings was not correlated to the concentration of ICCM in droppings. It is thus important that excretion of ICCM be expressed as amount excreted per time unit since the total excretion is dependant on both concentration of ICCM and amount of droppings produced.  相似文献   
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Bovine viral diarrhoea virus (BVDV) is an important cattle pathogen that causes acute or persistent infections. These are associated with immunotolerance to the viral strain persisting in animals that became infected early in their intrauterine development. To this date, the epidemiology of BVD in Switzerland runs virtually undisturbed by control measures such as restrictions on animal traffic or vaccination. Here, we analysed the viral genetics of 169 Swiss isolates and carried out crossed serum neutralisation tests to assess the antigenic spectrum of BVDV strains present in the cattle population. Besides confirming the presence of BVDV type 1 subgroups b, e, h and k, a single "orphan" BVDV-1 virus was detected that does not belong to any known BVDV-1 subgroup. No BVDV type 2 viruses were detected, suggesting that they are rare or not present in the cattle population. Antigenic comparison revealed significant differences between the different subgroups, with anti-1k immune serum having up to tenfold lower neutralising activity against 1b, 1e and 1h subgroup viruses, which however may still suffice to protect 1k-immune animals against superinfection by viruses of those other subgroups. Serum from routinely vaccinated animals revealed generally low titres but good cross-neutralisation. A geographic information system revealed that the viruses of the different subgroups are distributed in an apparently randomised fashion in the cattle population. This geographic distribution pattern may reflect peculiarities of the management practice in the Swiss cattle industry that, especially through annual transhumance of up to 25% of the entire population in the alpine region, tend to optimise the spread of BVDV.  相似文献   
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Surgical management of postamputation orthopedic disease (PAOD) in canine amputees has rarely been documented, and no reports describing outcome of stifle surgery in canine amputees are available. The objective of this multisite retrospective case series was to describe cases and evaluate satisfaction with and outcome of postamputation orthopedic surgery in canine amputees. Data was obtained through medical records and owner survey responses; data included signalment, amputation cause, diagnosis, surgical treatment, timeframes, and outcome assessment. Outcome was categorized as acceptable or unacceptable, and complications were classified as catastrophic, major, or minor. Eleven thoracic limb amputees and 6 pelvic limb amputees with surgically treated PAOD were identified. Surgically treated PAOD was reported at a median of 9.7 months (range 0.5-110 months) after amputation. All 17 amputees were treated for pelvic limb disease, predominantly for cranial cruciate ligament disease that occurred in 11 of 17 dogs. Major complications following orthopedic surgeries performed in 3 thoracic limb amputees consisted of infection (n?=?2) and uncontrolled pain (n?=?1). No major complications were reported following orthopedic surgeries performed in pelvic limb amputees. Acceptable mid-to-long-term outcome was achieved in 16 of the 17 canine amputees. Surgical treatment of pelvic limb disease did not appear to be associated with a high number of major complications in this case series. These findings suggest that orthopedic surgery, specifically stifle surgery, in canine amputees might be considered a feasible treatment option. Although there are inherent methodological limitations of retrospective studies and owner surveys, our case series provides new information that might help guide surgical treatment decisions in canine amputees suffering from orthopedic disease. Prospective studies using objective outcome measures evaluating surgical management of PAOD are necessary to confirm the provided information.  相似文献   
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Objective— To identify surgical techniques performed by veterinary surgeons for the treatment of cranial cruciate ligament disease in large-breed dogs with excessive tibial plateau angle (eTPA), compare their outcomes, identify risk factors for postoperative complications, and compare outcome and complication rate with tibial plateau leveling osteotomy (TPLO) in dogs without eTPA.
Study Design— Multicenter, case–control study.
Animals— eTPA group (TPA≥35°)=58 dogs (78 stifles); control group (TPA≤30°)=58 dogs (72 stifles).
Methods— Control and eTPA group dogs were identified. Medical records, radiographic reviews, and pet-owner interviews were used to identify surgical treatments performed, their complications, and outcome. Odds ratios with 95% confidence intervals, χ2 tests, and t-tests were calculated to discern differences between eTPA and control-group dogs.
Results— TPLO was the most common treatment for eTPA. Owner-perceived outcome was superior for eTPA group dogs when TPLO resulted in TPA≤14° compared with those with postoperative TPA>14°. Loss of tibial plateau leveling during convalescence was the most commonly observed major complication; addition of ancillary implants to TPLO significantly reduced its incidence. Postoperative complications were more common in dogs with eTPA than in dogs without eTPA; however, no difference in owner-perceived outcome was identified.
Conclusions— Surgical treatment of dogs with eTPA has a higher complication rate, but comparable outcome to that of dogs without eTPA.
Clinical Relevance— Postoperative TPA≤14° and addition of ancillary implants are recommended when using TPLO to treat dogs with eTPA.  相似文献   
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As in many underdeveloped regions of the world, some African countries are at present going through stages of rapid economic changes. Such changes include relatively rapid increases in national income, urbanisation, proportion of population going to school in the ‘modern’ sense, etc. In other words, the traditional sectors of many countries are gradually being transformed into modern ones. In Nigeria such changes are accelerated by the present high world market prices for petroleum products and expanded drilling for petroleum in Nigeria which generate high growth rates for national income.These changes have important consequences for wood consumption because, as traditional economic activities decline and modern ones expand, demand for fuelwood and unprocessed wood salvaged and used on the farm declines and demand for processed wood produced commercially expands.Part I of this paper, in a general way, specifies aspects of the Nigerian forestry sector which should be considered in formulating the systems simulation model of the sector. Part II specifies an analytical model which can simulate the transfer of population from the traditional to the modern sector as economic conditions improve and enable the consequences of such a transformation on wood consumption to be traced through time. The analytical model is also tested in Part II by using the model to predict the annual consumption of various wood products in Nigeria by the year 1990.  相似文献   
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Ponder  Felix 《New Forests》1988,2(3):195-201
Eight years after planting in a hardwood clearcut, black walnut trees in plots with weed control had significantly better survival and were taller and larger in diameter than those in plots without weed control. Planting autumn-olive with walnut also significantly increased height and diameter of the walnuts but did not affect their survival.  相似文献   
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