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121.
Previous studies in avian species have reported time-dependent losses in muscle glycogen with prolonged feed withdrawal (FW). However, cervical dislocation was used to collect tissues, a method that results in significant involuntary muscle convulsions. In this study, cervical dislocation alone was found to reduce muscle glycogen by 23%, therefore, barbiturate overdose was used to collect tissue samples before and after FW, at the end of refeeding, and from continuously fed controls at each interval. Additionally, plasma samples from 6-wk-old male chickens were taken at the initiation and end of a 24-hr feed withdrawal, and at various times during refeeding. After 24 hr of FW, liver glycogen decreased markedly (77%; P < 0.05), whereas muscle glycogen decreased slightly and transiently, such that it returned to and remained at control levels, even after prolonged (72 hr) FW. Plasma glucose was decreased, whereas glucagon was elevated after a 24-hr feed withdrawal (P < 0.05), when compared with control concentrations. Muscle glycogen levels were not significantly increased over control levels after refeeding, but liver glycogen was increased by 380% (P < 0.05). Feed deprivation followed by refeeding resulted in increased circulating insulin and glucose levels when compared with control levels. Therefore, by using methods of tissue collection that ensure that muscle glycogen determinations are not confounded by artifactual degradation, these results verify that regulation of avian muscle glycogen stores is similar to that in mammals.  相似文献   
122.
Protein‐dependent aquaculture generates large amounts of nutrient‐rich residuals; a feasible way to develop sustainable production systems is to integrate Decoupled Aquaponic Systems (DAPS) with residual water bioprocesses, to combine Photoautotrophic Biofloc Technology (P‐BFT) aquaculture and hydroponic horticulture. This study describes the characteristics of residual water from Oreochromis niloticus aquaculture performed with P‐BFT inoculated with Chlorella microalgae, reared during the nursery (180 fish m3) and grow‐out (55 fish m3) phases. The experiment included five treatments: photoautotrophic BFT inoculated with Chlorella sp. (M), C. sorokiniana 2714 (CV), and C. sorokiniana 2805 (CS), and chemoautotrophic (Q) and heterotrophic (H) as controls. Elemental characteristics in liquid and solid residual fractions (15 macro‐ and micronutrients) were compared among treatments and against Hoagland & Arnon solution with hydroponics and used in Nutrient Film Technique (NFT) hydroponic horticulture including five plant species: lettuce (Lactuca sativa), pak‐choi (Brassica rapa subsp. chinensis), rocket (Eruca sativa), spinach (Spinacia oleracea) and basil (Ocimum basilicum). The physicochemical parameters were ideal for O. niloticus and plants. The relationship between N:P was ideal until weeks 16–22 in the photoautotrophic treatments, compared with hydroponic solutions. Micronutrient content was greater in the solid than a liquid fraction. The best BFT effluent regarding fish and plant growth was photoautotrophic treatments. Oreochromis niloticus BFT aquaculture in photoautotrophic mode using microalgae Chlorella inoculations provided residual water beneficial to hydroponic horticulture in DAPS located in coastal arid zones where freshwater is scarce, improving aquaculture performance and reusing water and nutrients.  相似文献   
123.
Wild capture fisheries produce 90 million tonnes of food each year and have the potential to provide sustainable livelihoods for nearly 40 million people around the world ( http://www.fao.org/3/a-i5555e.pdf ). After decades of overfishing since industrialization, many global fish stocks have recovered, a change brought about through effective management. We provide a synthetic overview of three approaches that managers use to sustain stocks: regulating catch and fishing mortality, regulating effort and regulating spatial access. Within each of these approaches, we describe common restrictions, how they alter incentives to change fishing behaviour, and the resultant ecological, economic and community‐level outcomes. For each approach, we present prominent case‐studies that illustrate behaviour and the corresponding performance. These case‐studies show that sustaining target stocks requires a hard limit on fishing mortality under most conditions, but that additional measures are required to generate economic benefits. Different systems for allocation allow stakeholder communities to strike a locally acceptable balance between profitability and employment.  相似文献   
124.
125.
The fatty acid (FA) composition of nine potentially important forage species was determined (n = 330): red drum (Sciaenops ocellatus), spot (Leiostomus xanthurus), spotted seatrout (Cynoscion nebulosus), striped mullet (Mugil cephalus), pinfish (Lagodon rhomboides), Atlantic croaker (Micropogonias undulatus), star drum (Stellifer lanceolatus), striped anchovy (Anchoa hepsetus), and brief squid (Lolliguncula brevis). Samples were collected from estuarine and nearshore coastal waters around Charleston, South Carolina, USA, from March 2002–February 2003. Twenty-nine of 125 identified FAs were included in multivariate analyses of FA profiles. Despite existing intraspecific variation, the PRIMER routine analysis of similarity (ANOSIM) indicated each species was distinct, and discriminant function analysis correctly classified 99.5% of the training data set samples (n = 221) and 98.2% of the validation samples (n = 109). Most species could be characterized by distinctive levels of a suite of FAs. Our results indicated FA profiles can be used to reliably distinguish even closely related forage species in this southeastern US estuarine ecosystem. The information gained from this study not only provides insight into the biochemical composition of these important species but also provides fundamental information to support studies on the feeding ecology of local higher-level predators. The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.  相似文献   
126.
Lesquerella fendleri is a developing oilseed crop suitable for temperate growing regions in the US. The seed oil is rich in lesquerolic acid (57%) and could serve as a domestic source of hydroxy fatty acids. A method for the analysis of fatty acids and total oil content of a half or single lesquerella seed was developed. Lesquerella seeds are small with 1000 seed weights around 0.6 g (half seed mass of 200–500 μg). Conventional analytical balances provide mass accuracy to ±40 μg which fails to provide sufficient accuracy/precession (4–40% mass error) for the initial seed mass. A microbalance which measures to ±2 μg provided good reproducibility in initial seed weights but was not suitable for mass balance of the extracted oil. A normal phase HPLC coupled to an evaporative light scattering detector gave good response for oil in the mass range of 22 μg to 110 μg/mL. Therefore, micelle concentrations from single or half seed extractions could be determined with good reproducibility. This method was then evaluated on bulk seed that had been fractionated on a gravity table. Gravity table fractionation of L. fendleri seeds obtained from a large field plot provided seven fractions with increasing bulk density. These fractions were then analyzed in sets of 30 individual seeds and as an aggregate of 50 seeds. Oil content for individual seeds varied widely (15.6–44.2%) as did lesquerolic acid content (42.2–63.7%). The mean oil content increased (27–33%) with increasing bulk density (684–745 g/L). The mean lesquerolic acid content did not correlate with bulk density.  相似文献   
127.
The value of comparative oncology has been increasingly recognized in the field of cancer research, including the identification of cancer-associated genes; the study of environmental risk factors, tumor biology, and progression; and, perhaps most importantly, the evaluation of novel cancer therapeutics. The fruits of this effort are expected to be the creation of better and more specific drugs to benefit veterinary and human patients who have cancer. The state of the comparative oncology field is outlined in this article, with an emphasis on cancer in dogs.  相似文献   
128.
The West Nile (WN) virus, present in the United States since 1999, is a cause of encephalomyelitis in birds, alligators, humans, and horses. No data exist regarding detection of anti-WN virus immunoglobins in equine cerebrospinal fluid (CSF). The aims of this study were to evaluate the blood-brain barrier (BBB) in WN virus-infected (WNE) horses, to compare diagnostic testing in serum and CSF, and to describe the immunoglobulin M (IgM) response in serum and CSF of vaccinated horses. CSF was collected from the lumbosacral (LS) space (n = 13) or the allanto-occipital (AO) space (n = 14) of WNE horses. The albumin quotient (AQ) and IgG index were calculated, and the IgM-capture-enzyme-linked immunosorbent assay (MAC-ELISA) was used to detect anti-WN virus IgM in serum and CSF. CSF collected from the LS site had a higher (P < .02) IgG index compared to the AO site (0.34 +/- 0.04 versus 0.22 +/- 0.04 [mean +/- SE], respectively). The mean AQ, irrespective of collection site, did not exceed reference values. There was 100% agreement between CSF and serum testing for IgM by MAC-ELISA testing. However, the positive to negative antigen ratios were higher (P < .001) in CSF (34.5) versus serum (8.5), indicating lower nonspecific reactivity in CSF samples. Horses vaccinated against WN virus did not develop an IgM response at 1:400 mg/dL in serum; however, a few horses developed a weak IgM response in serum but not in CSF. In conclusion, MAC-ELISA testing of serum and CSF were equivocal. Also, examination of CSF data from WNE horses suggests a normal BBB integrity and increased intrathecal production of antibodies.  相似文献   
129.
This report describes a 3-year-old female Doberman pinscher dog with ligneous conjunctivitis and a protein-losing nephropathy not associated with underlying plasminogen deficiency. Glomerulonephropathy in this circumstance had a positive outcome.  相似文献   
130.
In this retrospective study, a chemotherapy protocol using dexamethasone, melphalan, actinomycin D, and cytosine arabinoside (DMAC) was evaluated for efficacy and adverse event profile as a first line rescue protocol in 86 client-owned dogs previously treated with a CHOP-based protocol. Forty-three dogs (43%) achieved remission (16% complete remission, 27% partial remission), and 57% were non-responders. The median overall progression-free survival (PFS) was 24 days. Adverse events included thrombocytopenia in 41% of dogs, neutropenia in 17% of dogs, and gastrointestinal toxicity in 13% of dogs. Overall, 16% (13/79) dogs experienced grade III to IV thrombocytopenia, 8% (6/74) dogs grade III to IV neutropenia and 1% (1/79) dogs grade III to IV gastrointestinal toxicity. The efficacy of the DMAC protocol is similar to that of other rescue protocols in dogs with relapsed lymphoma but is associated with shorter PFS. The main toxicity is thrombocytopenia, which may limit treatment.  相似文献   
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