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排序方式: 共有140条查询结果,搜索用时 468 毫秒
1.
The practice of catch-and-release fishing has been widely promoted by angling fraternities as a fisheries manage- ment tool. The aim of this investigation was to determine the physiological response of Orange-Vaal smallmouth yellowfish, Labeobarbus aeneus, to catch-and-release angling in the Vaal River, South Africa. Fish were collected using standard fly-fishing techniques, anaesthetised in clove oil and blood was drawn from the caudal vein; thereafter the fish were weighed, measured, revived and released. Blood plasma was analysed for concentra- tions of glucose, cortisol and lactate to determine the effects of angling duration, fish size and water tempera- ture. Larger fish were angled for a longer duration compared with smaller fish. Levels of glucose were affected by water temperature (influenced by time of year). Plasma glucose concentrations decreased with greater angling duration. Few individuals (n = 12) showed increased plasma cortisol concentrations. In extended-capture fish (angled for >1 min), lactate concentrations increased significantly above values for rapid-capture fish (angled for >30 s). These data suggest that catch-and-release causes physiological stress to fish, but nonetheless this practice can be a valuable fisheries management tool to ensure the sustainability of fish populations. Other factors beyond the ‘angling’ time are likely to contribute to physiological disruptions in homeostasis and therefore handling and air exposure of angled fish should be included in future catch-and–release angling studies. In addition, the longer-term impact of angling on fish health should also be determined. 相似文献
2.
A 6-mo-old female scarlet macaw (Ara macao) was presented after a 2-mo period of anorexia and weakness. The bird was reluctant to fly 1 wk before referral due to a painful left wing. Physical examination revealed a firm swelling around the left shoulder. On radiographs, the diaphysis and proximal metaphysis of the left scapula were radiolucent. Computer tomography revealed an osteolytic process, suggestive of a bone tumor, affecting the left scapula. Cytology of a fine needle aspiration biopsy of the mass showed erythrocytes, a proliferation of spindle-shaped mesenchymal cells, and multinucleated giant cells (osteoclasts) suggestive of a giant cell tumor. The left wing, including the scapula, was amputated. The bird showed a fast recovery but died 1 hr later. Findings during the pathological examination were compatible with shock due to blood loss. The shoulder process was characterized as a giant cell tumor. To our knowledge, this is the first complete report of a giant cell tumor of the bone in a bird. 相似文献
3.
Researchers have found that changes in infiltration characteristics that result from surged flow, often inferred from advance trajectories, vary considerably with site and management practices. Previously developed methods for adjusting the infiltration function for the surged effect are examined to better understand these effects. The easily implemented cycle ratio-time (CRT) surged flow infiltration function indicates that soil and management factors can impact surged flow effectiveness. If changes in flow rate result in changes in the on/off pulse patterns, the CRT function will reflect this with changes in infiltration characteristics; otherwise the model is insensitive to changes in flow rate. The duration of the first surge has a more pronounced effect than later surges, and soils that reach steady state infiltration quickly are less likely to exhibit decreased infiltration rates as a result of surged flow. Surged flow simulation runs are used to show that the CRT function predicts differences in performance on opposite sides of tee-type surge valves; the result of uneven off-times associated with expanding cycle times. 相似文献
4.
Malignant lymphoma is a common malignancy in birds. Paraneoplastic syndromes, which are commonly observed in domestic animals, have not been reported in association with lymphoma in birds. Hypercalcemia and hyperglobulinemia were found on plasma chemistry in two Amazon parrots, which were presented with aspecific symptoms. In both cases radiography and ultrasound demonstrated signs of hepatomegaly, which proved to be due to malignant lymphoma on postmortem examination. The hypercalcemia was found to be most consistent with a paraneoplastic effect of the malignant lymphoma in these birds. The exact origin of the hyperglobulinemia remains unclear. 相似文献
5.
6.
Protection of olive planting stocks against parasitism of root-knot nematodes by arbuscular mycorrhizal fungi 总被引:3,自引:0,他引:3
P. Castillo A. I. Nico C. Azcón-Aguilar C. Del Río Rincón C. Calvet R. M. Jiménez-Díaz 《Plant pathology》2006,55(5):705-713
The effects were investigated, under controlled conditions, of single and joint inoculation of olive planting stocks cvs Arbequina and Picual with the arbuscular mycorrhizal fungi (AMF) Glomus intraradices , Glomus mosseae or Glomus viscosum , and the root-knot nematodes Meloidogyne incognita and Meloidogyne javanica , on plant performance and nematode infection. Establishment of the fungal symbiosis significantly increased growth of olive plants by 88·9% within a range of 11·9–214·0%, irrespective of olive cultivar, plant age and infection by M. incognita or M. javanica . In plants free from AMF, infection by Meloidogyne spp. significantly reduced the plant main stem diameter by 22·8–38·6%, irrespective of cultivar and plant age. Establishment of AMF in olive plants significantly reduced severity of root galling by 6·3–36·8% as well as reproduction of both Meloidogyne spp. by 11·8–35·7%, indicating a protective effect against parasitism by root-knot nematodes. Infection by the nematodes influenced root colonization by AMF, but the net effect depended on the AMF isolate–olive cultivar combination. It is concluded that prior inoculation of olive plants with AMF may contribute to improving the health status and vigour of cvs Arbequina and Picual planting stocks during nursery propagation. 相似文献
7.
D. R. Eisenhauer 《Forest Pathology》1991,21(5):267-278
Taxonomy and pathogenicity of Ophiostoma piceae (Münch) Syd. in connection with dieback in sessile- and pedunculate oak stands of the Central German and the North Eastern German Diluvium Region. The loss of vitality resulting in the dying of oak forests is most probably caused by a complex of phytopathological factors. One part of this complex may be a vascular mycosis. In this connection Ophiostoma piceae (Münch) Syd. is one of the most discussed vascular fungi. Results of investigations on the variability of some morphological parameters, of cultural growth, of the pathogenicity and of the toxicity of metabolites are reported. 相似文献
8.
Tiebel Katharina Huth Franka Frischbier Nico Wagner Sven 《European Journal of Forest Research》2021,140(5):1299-1299
European Journal of Forest Research - The article “Restrictions on natural regeneration of storm-felled spruce sites by silver birch (Betula pendula Roth) through limitations in... 相似文献
9.
Amber M. Kameka Siamak Haddadi Fathima Jesreen Jamaldeen Prima Moinul Xiao T. He Fathima Hafsa P. Nawazdeen Stephan Bonfield Shayan Sharif Nico van Rooijen Mohamed Faizal Abdul-Careem 《Canadian journal of veterinary research》2014,78(4):274-282
Macrophages function as phagocytes and antigen-presenting cells in the body. As has been demonstrated in mammals, administration of clodronate [dichloromethylene bisphosphonate (Cl2MBP)] encapsulated liposomes results in depletion of macrophages. Although this compound has been used in chickens, its effectiveness in depleting macrophages has yet to be fully determined. Here, we show that a single administration of clodronate liposomes to chickens results in a significant depletion of macrophages within the spleen and lungs of chickens up to 4 d post-treatment. This finding suggests that, in order to obtain depletion of macrophages in chickens for greater than 5 d, it is necessary to administer clodronate liposomes 4 d apart. The study also showed that 2 treatments of clodronate liposomes at 4-day intervals resulted in the depletion of macrophages for up to 10 d. The findings of the present study will encourage more precise studies to be done on the potential roles of macrophages in immune responses and in the pathogenesis of microbial infections in chickens. 相似文献
10.
Chantal A.P.M. Verboven Sylvia C. Djajadiningrat‐Laanen Willem‐Jan P. Kitslaar Guy C.M. Grinwis Nico J. Schoemaker Michael H. Boevé 《Veterinary ophthalmology》2014,17(4):290-293
A 4‐year‐old intact male ferret was presented to the Ophthalmology Service of the Department of Clinical Sciences of Companion Animals of Utrecht University with chronic blepharospasm, epiphora, and conjunctivitis of the right eye. Examination of the eye revealed mild conjunctivitis and three hairs protruding from the openings of meibomian glands in the upper eyelid, providing the clinical diagnosis of distichiasis. The distichia were removed by transconjunctival unipolar electrocautery. Recovery was uneventful, but the original signs recurred 10 weeks after surgery. Ophthalmic examination revealed another distichia at a different location in the same eyelid and it was removed by full‐thickness wedge excision. Histopathological examination failed to reveal the exact origin of the distichia. To our knowledge, this is the first reported case of distichiasis in a ferret. 相似文献