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51.
The traditional whedo system involves the digging of large ditch-like ponds that fill seasonally with flood water, trapping fish which are subsequently harvested during the dry season. Although whedos are well described in the South of Benin, basic information necessary for their management in the North is lacking. Since 1998, the commune of Malanville has experienced a kind of ‘blue revolution’ because up to now, approximately 500 whedos (known locally as tschifi dais) have been constructed covering a total surface area of 9.3 ha, thus reflecting the high acceptance of the practice among the local population. Despite the fast development this system has received little attention from national development planners and international agencies, but in view of the disastrous state of the river Niger's fishery, sustainable aquaculture, fully relying on local species should be supported to release pressure on natural fish stocks. Instead of focussing all efforts on the introduction of modern aquaculture, it is important to enhance the existing system because of the knowledge and acceptance by the local population.

This paper characterizes the current management and the technical as well as economical features of the tschifi dais in the commune of Malanville, northern Benin.  相似文献   
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Substitution of fish meal (FM) as a protein source in aquaculture diets is required to reduce cost and promote a sustainable industry. Potential protein sources include a range of traditional products from agricultural production such as plant or animal proteins. However, there are also a number of manufacturing coproducts, including bacterial dried fermented biomass (DFB,) for which there is an increased interest. Hence, the objective of this study was to evaluate DFB as a replacement for FM in practical diets for Florida pompano, Trachinotus carolinus. Four diets were prepared in which different levels of FM (15%, 10%, 5%, and 0% of the diet) were replaced with DFB (0%, 4.27%, 8.54%, and 12.82%) on an iso-nitrogenous and iso-lipidic basis, to contain 40% crude protein and 10% lipid. A 10-week growth trial was conducted in a recirculating system consisting of 12 indoor 1.0 m3 tanks, stocked with 20 juvenile pompano (mean initial weight 8.1 g) per tank. There were no significant differences in final weight (64.5 g?79.5 g), survival (81.7%–96.7%), percent weight gain (711.6%–879.0%), FCR (2.1–2.0), or thermal-unit growth coefficient (0.1013?0.1149), regardless of the levels of dietary FM or DFB tested. Based on these results, it is recommended that DFB can be included up to 12.8% in practical diets for Florida pompano without significantly reducing growth performance. The response to higher levels of DFB inclusion should be evaluated.  相似文献   
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The objective of this study was to develop two methods to predict the volume of whole Alaska pollock and to compare the results with the experimentally measured volumes. One hundred fifty-five whole pollock, obtained from a Kodiak processor, were individually immersed in a graduated cylinder equipped with an outflow tube to catch the displaced water as a result of immersion. The weight of the water was recorded. Then the fish were placed in a light box equipped with a digital video camera, and the side view and top view recorded (2 images for each fish). A reference square of known surface area was placed by the fish. A cubic spline method to predict volume by integration of cross-sectional area slices based on the top and side views and an empirical equation using dimensional (length L, width W, depth D) measurements at three locations of the fish image were developed. The R2 value for the correlation between the L × W × D versus measured volume was 0.987. The best R2 for the correlation of the predicted volume by the cubic spline method versus the measured volume was 0.99. Image analysis can be used reliably to predict the volume of whole Alaska pollock.  相似文献   
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A 13‐year‐old, castrated male Maine Coon cat was presented to Oklahoma State University Boren Veterinary Medical Teaching Hospital for yearly echocardiographic examination monitoring hypertrophic cardiomyopathy (HCM) diagnosed in 2003. Physical examination revealed a heart murmur and premature beats, likely related to HCM, but was otherwise unremarkable. A biochemistry profile revealed a hyperglobulinemia (6.3 g/dL). Cytologic examination of fine‐needle aspirates from liver and spleen revealed increased numbers of plasma cells and mast cells, confirmed with subsequent histologic examination. Immunohistochemistry (IHC) for c‐kit in the spleen and liver showed mast cells predominantly exhibiting type I staining pattern, with moderate numbers exhibiting type II pattern in spleen, and scattered cells exhibiting type II and III patterns in liver. Bone marrow cytology and core biopsy documented approximately 22% plasma cells. Cutaneous masses on the cat's left shoulder and right carpus were cytologically confirmed mast cell tumors. Serum protein electrophoresis with immunofixation confirmed an IgG monoclonal gammopathy. This is an example of 2 hematologic neoplasms occurring simultaneously in a cat. Concurrent pathologies may be overlooked if a single disease is diagnosed and suspected of causing all clinical signs. Both neoplasms were well differentiated, and neoplastic cells could have easily been interpreted as a reactive population had a full workup not been performed. Missing either diagnosis could result in a potentially lethal outcome. Eleven months after diagnoses, the cat was clinically doing well following a splenectomy and oral prednisolone and chlorambucil chemotherapy. Globulins decreased to 4.9 g/dL.  相似文献   
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A 4-week-old male Pomeranian was presented with eyes that had remained closed since birth. Clinical examination of the orbits revealed that globes were bilaterally absent, suggesting clinical anophthalmos. Following ultrasound imaging of the orbits, a diagnosis of severe bilateral microphthalmos was made, a condition of rare occurrence with an etiology that is not fully understood.  相似文献   
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Objective – To evaluate the tolerance of a continuous positive airway pressure (CPAP) mask in tranquilized dogs and compare PaO2 in arterial blood in dogs receiving oxygen with a regular face mask or CPAP mask set to maintain a pressure of 2.5 or 5 cm H2O. Design – Prospective, randomized clinical study. Setting – University teaching hospital. Animals – Sixteen client‐owned dogs without evidence of cardiopulmonary disease were studied. Interventions – Eight animals were randomly assigned to each of 2 treatment groups: group A received 2.5 cm H2O CPAP and group B received 5 cm H2O CPAP after first receiving oxygen (5 L/min) by a regular face mask. Animals were tranquilized with acepromazine 0.05 mg/kg, IV and morphine 0.2 mg/kg, IM. An arterial catheter was then placed to facilitate blood sampling for pHa, PaO2, and PaCO2 determinations before and after treatments. Direct mean arterial pressure, heart rate, respiratory rate, and temperature were also recorded after each treatment. Measurements and Main Results – CPAP administration was well tolerated by all animals. The mean arterial pressure, heart rate, respiratory rate, temperature, PaCO2, and pHa, did not differ at any time point between groups. Differences were seen in oxygenation; in group A, PaO2 significantly increased from a mean of 288.3±47.5 mm Hg with a standard mask to a mean of 390.3±65.5 mm Hg with the CPAP mask and in group B, PaO2 increased similarly from 325.0±70.5 to 425.2±63.4 mm Hg (P<0.05); no differences were detected between the 2 CPAP treatments. Conclusions – In healthy tranquilized dogs noninvasive CPAP is well tolerated and increases PaO2 above values obtained when using a regular face mask.  相似文献   
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Journal of Crop Science and Biotechnology - Rice has been grown as a staple food in South Korea for several millennia. However, its status has not stayed constant as a result of changes in South...  相似文献   
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