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21.
Abdel-Fattah M. El-Sayed Cathrine R. Mansour Altaf A. Ezzat 《Aquaculture (Amsterdam, Netherlands)》2003,220(1-4):619-632
Effects of dietary protein level and water salinity on spawning performance of Nile tilapia broodstock and growth of their larvae were studied. Four isocaloric (400 kcal/100 g) diets containing 25%, 30%, 35% and 40% crude protein were prepared. The diets were fed to broodfish (25.7 g) reared at three water salinities (0‰, 7‰ and 14‰) at a female/male ratio of 3:1, to satiation twice a day for 195 days. The size at first maturation increased with increasing dietary protein at all salinities. At 25% and 30% protein levels, broodstock reared at 0‰ reached their sexual maturity at bigger sizes than those reared at 7‰ and 14‰. At 0‰, spawning intervals were not significantly affected by dietary protein levels. At 7‰ and 14‰, spawning intervals significantly decreased with increasing dietary protein level. Spawning frequency and number of eggs per spawn were increased with increasing dietary protein level. The total number of spawnings per female and absolute fecundity were better in fish fed 40% protein in freshwater than at 7‰ and 14‰ salinity. The relationship of dietary protein and water salinity on egg size was significant, but showed irregular patterns. The chemical composition of broodstock muscles, eggs and fry were not significantly affected by dietary protein and water salinity, except for body water and crude protein of broodstock which were significantly affected; but showed irregular trends. At each water salinity, egg hatchability was linearly increased with increasing dietary protein level. Eggs produced from broodstock fed 25% protein at 7‰ and 14‰ needed more time for hatching and yolk-sac absorption and resulted in poorer larval weight than those reared in freshwater. Fry growth was improved with increasing protein level at all salinities. This result revealed that 40% dietary protein is required for optimum spawning performance of Nile tilapia reared at 0‰, 7‰ and 14‰ salinity. It also indicated that spawning performance and larval growth were better in freshwater than at 7‰ and 14‰. 相似文献
22.
High performance fibers have distinguished properties such as high tensile strength, good thermal and chemical resistance, dimensional stability, lightweight, and high electrical conductivity. Due to these superior properties, high performance fibers made it to the scene of broad range of applications such as aerospace, automotive, windmill, fiber reinforced composites, high strength tethers, tendons for scientific balloon, tension structures, protective clothing, and marine. Examples of such fibers are Zylon®, Kevlar®, and Vectran®. However, the fibers lose their strength significantly upon exposure to Ultraviolet (UV) and visible light. In this research, UV protective films from extruded low density polyethylene (LDPE) loaded with different content of UV stabilizers (TiO2 nanoparticles and White PE CC®) were investigated. To assess the degree of UV blockage of each extruded protective film, their transmittance to UV and visible (UV-VIS) light was measured. Additionally, Zylon® braids were sheathed with the protective films and the strength of the braids and yarns raveled from braids was measured before and after UV exposure for different number of days. LDPE loaded with White PE CC® and 10 % TiO2 showed the least transmittance to UV-VIS and their yarns and braids exhibited highest strength retention after exposure to artificial UV. Strength retention of braids was higher than that of individual yarns due to weak link effect and braid structure assistant. 相似文献
23.
L. A. R. Sallam A. H. El-Refai M. Edrees A. F. Abdel-Fattah 《Plant foods for human nutrition (Dordrecht, Netherlands)》1974,24(1-2):159-162
Sterols were found to consitute 26% of the unsaponified lipid fraction of pigmented onion skins. Chromatography on alumina column did not achieve separation of onion sterols. By preparative thin-layer chromatography on silica gel G three onion sterols were isolated, i.e. stigmasterol, cholesterol and -sitosterol. Acetylation and benzoylation of these sterols were successfully performed on plates using silica gel G impregnated with silver nitrate.
Résumé Sterols ont été trouvés constituer 26% de l'unsaponifiable lipide fraction du peru des oignons pigmentés. Chromatographie sur le colonne d'alumina n'a pas accomplit la相似文献
24.
A field experiment was conducted on a sandy soil at Salhia El-Gdida, Al Sharqia government, Egypt, to study the effect of Moringa leaf extract on yield and nutrient uptake of wheat plants (Triticum aestivum cv.). Foliar spraying of Moringa leaf extract was done at 40, 70, and 90 days after planting at a rate of 0%, 1%, 2%, 3%, and 4%. Treatments of Moringa extract significantly increased straw and grain yield, biological yield, 1000 grain weight, yield efficiency, protein content, and nutrient uptake as compared to untreated plants in the both seasons. The highest values of straw and grain yield, quality yield, and nutrient uptake by plants were obtained with 4% of Moringa extract, while the lowest values were obtained with untreated plants. Also, the highest percentage increase in grain yield of 71% and 88% was recorded from the treatment 4% of Moringa extract in first and second seasons, respectively. 相似文献
25.
Souleymane Sanogo Mohamed Momani Shaker Hamidou Nantoumé Abdel-Fattah Z. M. Salem 《Tropical animal health and production》2012,45(1):305-310
The aim of this study was to evaluate milk yield and its composition during the preweaning period for Sahelian goats (SG) and Anglo-Nubian (AN) crossbred depending on some factors. The experiments were conducted from January to December 2008 for 44 suckled and hand-milked does, randomized, and divided into two equal groups: SG (n?=?22) and F1 Anglo-Nubian × Sahelian goats (1/2AN; n?=?22). The does and their offsprings were kept in a pen where they stayed indoors for 45 days before they were allowed outdoors when the weather was suitable. Each category received supplemental feeds depending on the season (rainy season, dry cold season, and dry hot season). The average daily milk yield was recorded weekly from parturition to 100 days of age. Individual milk samples were taken for chemical analysis in connection with the yield measurements twice per month from the fourth week of lactation throughout the different seasons (rainy, cold dry, and hot dry). The daily milk yield differed between breed types (P?=?0.001) during the preweaning, while the effect of kids' sex on daily milk production was not significant. Litter size affected milk yield up to day 60 (P?=?0.032) where does with twins producing more milk than those with single kid. However, at day 100, both groups had similar (P?=?0.001) milk production. Total milk yield at weaning increased by 103 % in 1/2AN over SG. The highest concentration of total solids of milk was (12.76 %) recorded in the hot dry season. The results of this study indicate that crossbreeding native Sahelian goats with high potential Anglo-Nubian buck improved milk production and its composition. 相似文献
26.
A F Abdel-Fattah E H Mohamed E S Mohamed G Ramadan 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(7):811-817
The effects of crude thymus extract on the immune response and protection against challenge with virulent infectious bursal disease virus (IBDV) were studied in one-day-old chick. Oral administration of thymus extract (1 ml/kg) markedly and significantly increased the total protein, albumin, globulin, Tri-iodothyronine (T3), Thyroxine (T4) and the body weight gain in one-day-old chick. In addition, it increased the total lymphocytic count over four weeks after administration. Although vaccination also increased total protein, globulin, T4 and the total lymphocytic count but it significantly decreased the body weight gain of the chick and administration of thymus extract, before, during or after vaccination markedly improved the vaccination effectiveness with significant elevation of the globulin level and body weight gain of the chick. It also prevented the decrease in the relative weights of bursa, spleen and thyroid gland which commonly prevailed during vaccination. Chicken administered thymus extract and vaccinated with infectious bursal disease (IBD) vaccine showed 100% protection against challenge with IBDV. Meanwhile the vaccinated non-thymus treated group exhibited 80% protection against IBDV challenge. These results indicate a potentiating effect of thymus extract on the immune system in baby chick. These findings are supported by ELISA results that showed a marked increase in antibody titers in thymus treated groups. Additionally, microscopical examination of the bursa and the existent lymphoid hyperplasia in thymus treated groups but not vaccinated group support our findings. 相似文献
27.
Despite the advances in woven fabrics, CAD systems, and weaving technologies, the process of weave/color selection for each area of a Jacquard pattern still requires the intervention of the CAD system operator and/or designer, who works from color gamut. Relying on the designer subjective assessment, multiple weaving trials may be needed to produce a fabric that matches the target artwork or sample. In this paper, a general geometric model is provided to predict the color contribution of warp and filling yarns of a given woven fabric in terms of warp and pick densities, warp and filling yarns sizes, weave, size of the color repeat of warp and filling yarns, and the number of yarns of different colors. Such geometrical modeling, combined with sound existing color mixing equations, paves the road for the automation of the process of weaves and color selection and thus dramatically reduces the production cycle. 相似文献
28.
M. Edrees M. M. Abbassy A. F. Abdel-Fattah 《Plant foods for human nutrition (Dordrecht, Netherlands)》1974,24(1-2):55-60
Lupinus termis seeds contain appreciable amounts of lipids and sterols. The lipid and sterol contents varied with the variety of seeds and the extracting agent. Cholesterol, stigmasterol and -sitosterol have been shown to be the main sterol compounds of the seeds. The presence of vitamin A, B1 and C inL. termis seeds has also been demonstrated.In Egypt,Lupinus termis seeds are mainly used for edible purpose. In a preceding paper (Abdel-Fattah et al. 1973) we reported on some constituents of these seeds, including carbohydrates, proteins and amino acids. For a further evaluation ofL. termis seeds we now report on their sterols and vitamins.
Zusammenfassung Lupinus termis Samen enthalten merkliche Mengen an Lipiden und Sterolen. Die Lipidund Sterolgehalte der Samen hängen von der Sorte und dem jeweiligen Extraktionsmittel ab. Cholesterol, Stigmasterol und -Sitosterol sind die Hauptsterolkomponenten der Samen. Außerdem wurden Vitamin A, B1 und C in den Samen vonLupinus termis nachgewiesen.
Résumé Les grains deLupinus termis contiennent des appreciables quantités de lipides et de stéroles. Les contenants de lipide et de stérole sont variés selon la varieté des grains et l'agent de l'extraction. Cholesterole, stigmasterole et -sitosterole ont été parus être les contenants essentials du stérole des grains. La présence de vitamines A, B1 et C dansL. termis a été encore démonstrée.相似文献
29.
Mohammad Al Amoudi Abdel-Fattah M. El-Sayed Ahmed El-Ghobashy 《Journal of the World Aquaculture Society》1996,27(4):456-461
Abstract.— The effects of thermal and thermo/haline shocks on the tilapias Oreochromis mossambicus and O. aureus × O. niloricus hybrids were investigated. Fingerlings were transferred abruptly from 25 C fresh water to fresh water or salt water (26 ppt) maintaining temperatures of 15, 20, 30 and 35 C. In fresh water, fish survival was not affected by temperature shock, but they suffered from a chill coma and developed fungal infection at 15 C. In salt water, thermo-haline shock did not affect the survival of O. mossambicus , while the survival rates of tilapia hybrids were 6.7, 100, 100, 70 and 59.7% at 15, 20, 25, 30 and 35 C, respectively. Plasma osmotic concentrations of O. mossambicus transferred to 15 and 35 C salt water were quickly and sharply increased, but gradually decreased to lower levels. Osmotic concentrations of tilapia hybrids were also increased, but never returned to their initial (lower) levels over one week. This study revealed that these fishes are more tolerant to high rather than low temperature shocks and O. mossambicus are more resistant to thermo-haline shocks rather than tilapia hybrids. It also indicated that thermo-haline shocks should be minimized during fish transportation and acclimation. 相似文献
30.
This study was conducted to evaluate the effects of photoperiod on the growth, feed conversion ratio (FCR) and spawning performance of Nile tilapia (Oreochromis niloticus) broodstock. Duplicate groups of two males (66±3.04 g) and six females (50.5±1.58 g) were stocked in 0.4 m3 fibreglass tanks in a recirculating water system at a male:female ratio of 1:3. The fish were subjected to four photoperiod treatments: 24:0 light:dark (L:D), 18L:6D, 12L:12D and 6L:18D. Light intensity was kept constant at about 2500 lx throughout the study. The fish were fed a commercial tilapia diet (35% crude protein and 16.6 MJ GE kg−1) at a daily rate of 2–3% of tank biomass, twice a day, for 130 days. Males grew significantly faster than females under all photoperiod regimes. The best growth rate and FCR were attained at 18L:6D, followed by 24L:0D, 12L:12D and 6L:18D respectively. The number of eggs per female, number of eggs per spawn and number of spawnings per female were all significantly higher in the 12L:12D treatment than in all other photoperiod cycles. Interspawning intervals and days elapsed per spawn were also shorter in the 12L:12D treatment. The time to first spawning was slightly longer in the 24L:0D and 6L:18D than in 12L:12D and 18L:6D light phases. The 18L:6D and 6L:18D photoperiods produced the lowest spawning performance. It is concluded that a 12L:12D photoperiod regime should be adopted for maximum fecundity, seed production and spawning frequencies of Nile tilapia broodstock reared in intensive, recirculating systems. If maximum reproduction is desired, a near‐natural day length photoperiod should be used. 相似文献