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51.
Stepwise function of natural growth for Scylla serrata in East Africa: a valuable tool for assessing growth of mud crabs in aquaculture 下载免费PDF全文
Per‐Olav Moksnes David Oersted Mirera Emma Björkvik Muumin Iddi Hamad Humphrey Matalu Mahudi Daniel Nyqvist Narriman Jiddawi Max Troell 《Aquaculture Research》2015,46(12):2938-2953
Predicting growth is critical in aquaculture, but models of growth are largely missing for mud crab species. Here, we present the first model of natural growth in juvenile and adult mud crabs Scylla serrata from East Africa using a stepwise growth function based on data on intermoult periods and growth at moult from field mark‐recapture, pond and laboratory studies. The results showed a sigmoid growth pattern in carapace width and suggest that S. serrata in East Africa will reach 300 g and sexual maturity ~9.9 months after settlement, and a commercial size of 500 g after 12.4 months. Analyses of the literature identified several issues with the common praxis to compare standard growth measures between aquaculture studies with different initial size or growing periods. Using the new growth function to estimate the proportional difference between modelled and obtained growth as an alternative method, we show that growth rates of S. serrata cultured in cage systems, which are dominant in East Africa, was <40% of the estimated natural growth and growth obtained in pond systems. The analysis also indicated that growth rates of S. serrata in Southeast Asia was over 50% higher compared with similar culture systems in East Africa, and that different species of mud crabs had large differences in growth rates. This study shows that growth in the present mud crab aquaculture systems in East Africa is below their expected potential. Further work is needed to identify the factors behind this observation. 相似文献
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53.
Bauer NB Bassett H O'Neill EJ Acke E 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):123-125
A 6-year-old, intact female, Labrador Retriever/Terrier cross was presented to the University Veterinary Hospital, University College Dublin with a 3-week history of therapy-resistant cervical pain and intermittent fever. Physical examination findings included marked cervical pain resulting in neck extension and vocalization. Examination of the CSF revealed mild pleocytosis (total nucleated cells = 0.009 x 10(9)/L, reference interval <0.005 x 10(9)/L). Cytocentrifuged preparations of the CSF were of low cellularity, containing predominantly macrophages and occasional small lymphocytes. Several small- to medium-sized fragments of a slightly granular, amorphous, eosinophilic substance were observed. The majority of mononuclear cells were located within this material, in small groups of 3-13 cells. The amorphous foamy material stained positive with Luxol fast blue, suggestive of myelin-like material. The dog was euthanized and postmortem examination revealed intervertebral disk protrusion between C2 and C3. Hematoxylin- and Luxol fast blue-stained histopathologic sections of brain and spinal cord revealed only mild hemorrhage. The extracellular material in the CSF of this dog may have been caused by myelin degeneration or leakage of phospholipids from damaged cells. Because no histologic evidence of demyelination was observed with the disk extrusion, the myelin-like material in this case was thought to be the product of phospholipid breakdown from damaged cellular membranes. Three cases of dogs with spinal cord disease and myelin-like material in the CSF have been reported previously. The clinical significance of this finding is still unknown. 相似文献
54.
Damaris Godinez-Vidal Mario Rocha-Sosa Edgar B. Sepúlveda-García Joel Lara-Reyna Reyna Rojas-Martínez Emma Zavaleta-Mejía 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(3):299-303
We tested the hypothesis that PAL activity in chilli plants CM-334 inoculated with Nacobbus aberrans (Na) alone or in combination with Phytophthora capsici (Pc), is lower than in those inoculated only with Pc. At 21 days after nematode inoculation, inoculated plants showed a significant
(P < 0.01) reduction of 48% in PAL activity compared to those non-inoculated in two separate experiments. In two other tests,
where plants were inoculated with the oomycete 21 days after inoculation with the nematode, PAL activity at 2, 4, 6, 8 and
24 h after inoculation with Pc was significantly higher (Tukey, P < 0.01) in plants inoculated only with Pc than in plants inoculated only with Na or both pathogens (Na+Pc). 相似文献
55.
Over half of the endangered species in the United States depend on private lands for habitat. In 1982, Congress amended the Endangered Species Act (ESA) to address the conservation of endangered species on private lands through the introduction of Habitat Conservation Plans (HCPs). HCPs enable landowners to comply with the ESA and can foster creative partnerships between the federal government and local stakeholders. Researchers have investigated the scientifically biological merits of HCPs, but comparatively little attention has been given to social aspects despite an emphasis on stakeholder involvement in HCPs. We explore stakeholder perceptions of HCP development through 19 semi-structured key informant interviews. Findings include the influence of interpersonal themes, shared understanding and capacity on process outcomes, and the importance of the external context in which HCP development occurs. Our research highlights the central role of understanding social dimensions to achieve the desired outcomes from collaborative conservation planning processes. 相似文献
56.
Long‐term Treatment with Methylene Blue in a Dog with Hereditary Methemoglobinemia Caused by Cytochrome b5 Reductase Deficiency 下载免费PDF全文
J.A. Jaffey M.R. Harmon N.A. Villani E.K. Creighton G.S. Johnson U. Giger J.R. Dodam 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2017,31(6):1860-1865
A juvenile male mixed breed dog was presented for lethargy, exercise intolerance, and aggression when touched on the head. Cyanosis, tachycardia, and tachypnea were observed and persisted during oxygen supplementation. Arterial blood gas analysis by co‐oximetry identified an increased methemoglobin concentration (27%; normal, <2%) with normal arterial oxygen tension. The methemoglobinemia and associated clinical signs resolved after administration of methylene blue (1 mg/kg) IV, and the dog was discharged. The affected dog's whole‐genome sequence contained 2 potentially causal heterozygous CYB5R3 missense mutations suggesting that cytochrome b5 reductase deficiency was responsible for the methemoglobinemia. This hypothesis was confirmed by enzyme analysis that identified cytochrome b5 reductase activity in the affected dog's erythrocytes to only approximately 6% of that in a control sample. Clinical signs recurred 11 days after discharge but normalized and the methemoglobin concentration decreased with methylene blue administration PO (1.5 mg/kg, initially daily and then every other day). 相似文献
57.
Method comparison and generation of plasma biochemistry RIs for the White rhinoceros on a point‐of‐care and wet chemistry analyzer 下载免费PDF全文
58.
Harold E. Burkhart Amy M. Brunner Brian J. Stanton Richard A. Shuren Ralph L. Amateis Jerre L. Creighton 《New Forests》2017,48(4):479-490
Poplar species grow well across the temperate zone, but hybrid varieties have not previously been evaluated for planting in the Virginia Piedmont region. The top 12 clones in height growth and rust resistance from a screening trial involving 98 hybrid poplar varieties of three taxa (Populus deltoides × P. maximowiczii, DxM; P. deltoides × P. nigra, DxN; P. deltoides × P. trichocarpa, DxT) were selected for planting in replicated yield trials at two locations in the Virginia Piedmont. Results through the first four growing seasons showed that the DxM taxon had the most rapid height development. It was, however, the taxon most affected by a late spring frost at the Appomattox-Buckingham State Forest site and by Septoria stem canker at the Reynolds Homestead site. Analysis of variance of clonal and location effects showed highly significant differences among replicates within location and among clones within taxon. Among seven clones within the DxM taxon, pairwise comparison tests of height growth identified two groups: a group of four better clones that were significantly different (p = 0.05) from a second group of three. These early results suggest that multi-selection criteria, including growth, disease and frost resistance, are important when developing hybrid poplar clones for planting in the Piedmont region. 相似文献
59.
Emma J. STOKES 《Integrative zoology》2010,5(4):363-377
Wild tigers are in a critical state with an estimated population decline of more than 95% over the past century. Improving the capacity and effectiveness of law enforcement in reducing poaching of tigers is an immediate priority to secure remaining wild populations in source sites. From 2008–2010, standardized patrol-based law enforcement monitoring (LEM) was established under the Tigers Forever Program across 8 key tiger sites in order to improve and evaluate law enforcement interventions. Patrol-based monitoring has the distinct advantage of providing regular and rapid information on illegal activities and ranger performance, although, until recently, it has received relatively little scrutiny from the conservation community. The present paper outlines a framework for implementation of LEM in tiger source sites using MIST, a computerized management information system for ranger-based data collection. The framework addresses many of the technical, practical and institutional challenges involved in the design, implementation, sustainability and evaluation of LEM. Adoption of such a framework for LEM is a cost-effective strategy to improve the efficiency of law enforcement efforts, to increase the motivation of enforcement staff and to promote the accountability of law enforcement agencies in addressing threats to tigers. When combined with independent, systematic and science-based monitoring of tigers and their prey, LEM has great potential for evaluating the effectiveness of protection-based conservation investments. 相似文献
60.