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The marine copepod species Oithona nana is considered as one of the most successfully mass cultured Cyclopoida species in marine hatcheries. This study investigated the effects of four feed diets (soybean, yeast, rice bran, and corn starch) on the population growth, growth rate, population composition, fecundity, and fatty acid composition of native isolated Cyclopoida copepod species O. nana. The experiment was continued for 15 days and the copepods were fed on one of the four diets with a concentration of 1 g 10-6 individual day-1. The results revealed that corn starch was found to be the most supportive diet for population growth and population growth rate. For nutritional value, copepods fed on rice bran were detected to have the highest content of MUFA, PUFA, and the lowest SFA and SFA/UFA ratio; more importantly, the rice bran diet was the only treatment that showed C20:5ω3. Moreover, copepods fed on rice bran showed the highest significant female fecundity, copepodite, and nauplii percent. Finally, the protocols described in the current study concluded that the dry feeds, especially corn starch, are very useful and applicable in hatcheries for maximizing the fecundity and density of Cyclopoida copepod species, O. nana.

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This study evaluated the effects of different levels of dietary lipids on the growth performance, feed utilization, body composition and cold tolerance of Nile tilapia (Oreochromis niloticus) fingerlings (7.33 ± 0.12 g fish-1). Four isonitrogenous (275 g kg-1 crude protein), isocaloric (18.5 MJ kg-1) diets containing a mixture of fish oil and corn oil (1:1 ratio) at different levels (70, 85, 110 and 130 g kg-1) were prepared and fed to Nile tilapia reared at a fixed water temperature 25 ± 1 °C for two months. After the feeding trial, the fish were exposed to a cold challenge. The best growth rates and feed utilization were achieved at 70 and 85 g kg-1 dietary lipid, whereas the lowest results were recorded at higher lipid levels (110 and 130 g kg-1). The ability of Nile tilapia to survive the acute cold stress was significantly improved as the lipid level increased from 70 to 110 g kg-1 and decreased with further increase in lipid levels. During the cold stress, saturated fatty acids (SFA) significantly decreased, while unsaturated fatty acids (UFA) tended to increase. Thus, this study demonstrates, to a certain level, that high dietary lipid levels have a positive effect on the cold tolerance of Nile tilapia fingerlings.

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This study was carried out to evaluate the effects of dietary lipid sources on growth performance, fatty acids composition and cold tolerance of Nile tilapia (Oreochromis niloticus) fingerlings (7.00 ±â€¯0.50 g/fish). The fish were fed four isonitrogenous (28% crude protein), isocaloric (500 kcal/100 g) diets containing four lipid sources; fish oil (FO), corn oil (CO), coconut oil (COCO) or fish oil/ corn oil mixture (1:1 ratio) (oil mix). The diets were offered to the fish at a daily rate of 3% of their body weights (BW), twice a day for two months. After the feeding trial, the fish were exposed to decreasing water temperature from 25 °C until the appearance of death symptoms. The results revealed that FO-based diets (FO and oil mix) produced the best growth rates and feed efficiency, followed by corn oil diet, while COCO resulted in the lowest performance. Fish fed on CO and oil mix showed higher body unsaturated fatty acids (UFA) and lower lethal temperature than those fed on FO- or COCO-based diets. These results indicate that cold shock can modify the lipid metabolism in Nile tilapia by lowering total body saturated fatty acids and raising n-6 and n-3 UFA. This finding suggests that the inclusion of high levels of plant oils in Nile tilapia feeds can enhance their cold tolerance.

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Coastal aquaculture is faced with extreme variation in water quality. The Deeba Triangle on Lake Manzala is the largest marine coastal aquaculture-producing area on the Egyptian Mediterranean. Samples from 16 ponds were taken during four seasons (2014-2015), to investigate the variation of 12 water quality parameters at that region. We tested the hypothesis that there is no spatial or temporal variation in water quality of the fish ponds. Fish ponds were statistically clustered into three groups (p = 0.0005) coincident with their geographical location. Hypersaline and transparent waters characterized the western ponds; higher dissolved oxygen and higher nutrients characterized the central region. These spatial differences were principally due to variations in salinity and nutrients of the water sources used for irrigation of the ponds and to differences in the aeration management styles. Strong seasonality was seen in water temperature (following air temperature), nutrients, and turbidity (following the seasonal cycles of various water sources from the Lake Manzala and the seasonality of the petrochemical plants effluents close to these ponds). We conclude that municipal effluents significantly affected, spatially and temporally, the quality of the irrigation water used for coastal aquaculture purposes, which consequently might affect fish yield.

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OBJECTIVE: To examine the in vitro antimicrobial effect of a 20% Miswak extract against a mixture of Candida albicans (C. albicans) and Enterococcus faecalis (E. faecalis) using the dilution tube susceptibility test, which allows direct contact between the tested material and the microorganisms. METHODS: The study samples were collected and processed between August 2009 and January 2010 in the College of Dentistry, King Saud University, Riyadh, Saudi Arabia. Each microorganism was obtained in a suspension and exposed to a 20% Miswak extract in plastic tissue culture clusters containing 24 wells. Six wells were used per group. The Miswak extract was incubated with the microorganisms for one, 6, and 24 hours. RESULTS: This in vitro study showed that Miswak extract was an effective antifungal and antibacterial agent at all tested experimental time periods, except one hour exposure of a 20% Miswak extract to E. faecalis and a mixture of E. faecalis and C. albicans, which was ineffective in inhibiting their growth. CONCLUSION: Twenty percent Miswak extract is an effective antifungal and antibacterial agent against C. albicans and E. faecalis.

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OBJECTIVE: This study was a prospective evaluation of surgical indications and outcomes for unilateral and bilateral bronchiectasis according to hemodynamic (functional and morphologic) classification. METHODS: Between January 1998 and January 2004, the morphologic features (cystic versus cylindric) by chest computed tomography and the hemodynamic features (perfused versus nonperfused) by lung ventilation/perfusion scan were determined in 66 patients with bronchiectasis (53 unilateral and 13 bilateral). The indication for surgical resection in both groups was the presence of localized areas of cystic, nonperfused bronchiectasis. RESULTS: In the unilateral bronchiectasis group, there were 28 female and 25 male patients with an average age of 37.5 +/- 3.8 years (range 6-40 years). Pneumonectomy was performed in 10 cases (8 left and 2 right), and lobectomy or bilobectomy was performed in 43. In the bilateral group, there were 7 male and 6 female patients with an average age of 42 +/- 5.4 years (range 9-55 years). Pneumonectomy was performed in 2 cases, lobectomy in 5, and bilateral staged lobectomy in 6. There was 1 postoperative death (1.5%), and morbidity was 18% (12 patients). Four patients required reexploration for bleeding, 4 had prolonged air leak develop, 3 acquired pulmonary infections, and 1 had localized empyema develop. During a mean follow-up of 52 months (range 24-82 months), 48 patients were considered cured (73%) and 17 had symptomatic improvement (26%). Pseudomonas infection and underlying chronic obstructive airway disease were poor prognostic factors (P < .05). CONCLUSION: The hemodynamic (functional and morphologic) classification provides an accurate functional classification for bronchiectasis. Its application in determining the indications and extent of surgical resection is superior to morphologic classification alone. Curative resection can be achieved in both unilateral and bilateral bronchiectasis with acceptable morbidity.

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We report two cases of unusual presentation of rib exostosis. The first patient presented acutely with hemorrhagic shock due to massive hemothorax, and the second patient presented with repetitive chest infection complicated by empyema. In both patients, preoperative computed tomographic (CT) scan of the chest revealed rib exostoses, necessitating thoracotomy and rib resection.

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