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1.
Barbour E.K. Bouljihad M. Hamdar B. Sakr W. Eid A. Safieh-Garabedian B. 《Veterinary research communications》1999,23(3):191-200
The dynamics of the serum concentration of protein 27 (P27) of avian leukosis virus and transforming growth factor 2 (TGF-2) were compared during the period between 29 and 59 weeks of age in two flocks of broiler chicken breeding stock undergoing outbreaks of severe lymphoid leukosis (LL) associated with persistent high mortality (susceptible) and in another two flocks of breeding stock with the presence of avian leukosis virus in association with low mortality due to LL (resistant). The average mean concentration of serum P27 in the LL-susceptible flocks was significantly higher (<0.05) than that in the LL-resistant flocks in six out of seven samplings performed at 5-week intervals, between 29 and 59 weeks of age. The peak in the average rise of serum P27 in the LL-resistant flocks (309 pg/ml) was associated with the highest level of TGF-2 (1282 pg/ml) among all flocks and at all sampling times. The significance of TGF-2 in inhibition of lymphoid tumour development is discussed. 相似文献
2.
Sakr Nachaat Ducher Mireille Delmotte Francois Vear Felicity Tourvieille Jeanne Walser Pascal de Labrouhe Denis Tourvieille 《植物病害和植物保护杂志》2011,118(3-4):141-141
Journal of Plant Diseases and Protection - 相似文献
3.
Sabreen E. Fadl Ghada A. El‐Gammal Walied S. Abdo Mohamed Barakat Osama A. Sakr Eldsokey Nassef Doaa M. Gad Hamdy S. El‐Sheshtawy 《Aquaculture Research》2020,51(3):1120-1132
The present investigation aimed to evaluate the effect of dietary chitosan supplementation on growth performance, body composition, immune response and histopathology of Nile tilapia, and also the in vitro antibacterial activity of chitosan against Streptococcus agalactiae (S. agalactiae). About 180 fish (average body weight 39.3 ± 0.3 g) were randomly divided into three groups according to chitosan supplementation: control group (basal diet without chitosan), Ch3 group (3 g chitosan/kg diet) and Ch5 group (5 g chitosan/kg diet). Growth performance parameters and body proximate composition were measured before infection but biochemical parameters and lysozyme and antibacterial activities before and after experimental infection. Results of the present investigation showed dietary chitosan (5 g chitosan/kg diet) significantly (p < .05) improved growth performance parameters, body composition (dry matter, crude protein, ether extract, ash, and carbohydrate) and serum biochemistry (total protein, albumin, globulin, with no effect on AST, ALT, urea and creatinine) before infection in Ch5 group than the control. After infection, liver enzymes (serum AST and ALT) were maintained lower in fish fed Ch3 or Ch5 than the control. Serum lysozyme and bactericidal activities significantly increased (p < .05) in chitosan groups before and after the challenge. The mortality rate was markedly reduced in the Ch3 group and prohibited in the Ch5 group after the experimental infection. In conclusion, feeding 3 or 5 g chitosan/kg diet increased the growth rate and improved FCR of Nile tilapia. In addition, it reduced mortality by its antibacterial and immunostimulant effects. 相似文献
4.
Norhan E. Saleh Shymaa M. Shalaby Eman M. Sakr Asmaa I. Abd Elmonem Fady R. Michael 《Journal Of Applied Aquaculture》2013,25(3):197-207
Five different levels (0, 25, 50, 75, and 100 g kg?1) of algal (Ulva fasciata) meal were added to red tilapia feeds to examine its effect on growth and carcass biochemical content. Addition of ulva meal significantly improved growth performance, feed utilization, total crude protein content, and percentage of highly unsaturated fatty acids. Fish fed 75 g kg?1 or 100 g kg?1 of U. fasciata performed better than others. 相似文献
5.
Journal of Plant Diseases and Protection - Variability in aggressiveness was studied in seven Plasmopara halstedii (sunflower downy mildew) parental isolates of races 100, 300, 304, 314, 704, 710... 相似文献
6.
Alves G Ameglio T Guilliot A Fleurat-Lessard P Lacointe A Sakr S Petel G Julien JL 《Tree physiology》2004,24(1):99-105
We studied seasonal variation in xylem sap pH of Juglans regia L. Our main objectives were to (1) test the effect of temperature on seasonal changes in xylem sap pH and (2) study the involvement of plasma membrane H+-ATPase of vessel-associated cells in the control of sap pH. For this purpose, orchard-grown trees were compared with trees grown in a heated (> or = 15 degrees C) greenhouse. During autumn, sap pH was not directly influenced by temperature. A seasonal change in H+-ATPase activity resulting from seasonal variation in the amount of protein was measured in orchard-grown trees, whereas no significant seasonal changes were recorded in greenhouse-grown trees. Our data suggest that H+-ATPase does not regulate xylem sap pH directly by donating protons to the xylem, but by facilitating secondary active H+/sugar transport, among other mechanisms. 相似文献
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8.
Spatial activity and expression of plasma membrane H+-ATPase in stem xylem of walnut during dormancy and growth resumption 总被引：1，自引：0，他引：1
Alves G Decourteix M Fleurat-Lessard P Sakr S Bonhomme M Améglio T Lacointe A Julien JL Petel G Guilliot A 《Tree physiology》2007,27(10):1471-1480
Plasma membrane H+-ATPase (PM H+-ATPase) plays a key role in nutrient transport, stress responses and growth. To evaluate proton motive force differences between apical and basal parts of acrotonic 1-year-old shoots of walnut (Juglans regia L. cv 'Franquette') trees, spatial and seasonal changes in PM H+-ATPase were studied in mature xylem tissues. During both the dormancy and growth resumption periods, and in both the apical and basal parts of the stem, PM H+-ATPase activity showed positive correlations with the amount of immunodetectable protein. In spring, at the time of growth resumption, higher activities and immunoreactivities of PM H+-ATPase were found in the apical part of the stem than in the basal part of the stem. In spring, the decrease in xylem sugar concentration reflected the high sugar uptake rate. Our data suggest that PM H+-ATPase plays a major role in the uptake of carbohydrates from xylem vessels during growth resumption. These results are discussed in the context of the acrotonic tendency of walnut shoots. 相似文献
9.
There is an increasing trend towards the replacement of fish oil (FO) by vegetable oils in feeds for farmed fish, particularly marine carnivores. Previous researches on partial or complete replacement of FO by alternate vegetable oils for young gilthead seabream (Sparus aurata) were successful. The aim of the present study was to investigate the effects of different dietary vegetable oils on seabream growers' health and liver structure. Two dietary vegetable oil blends (Mix 1 and Mix 2), namely sunflower oil, cottonseed oil and either linseed oil (LO) or soybean oil (BO), were tested as 60% FO substitutes versus the 100% FO control (CTR) diet. Three isonitrogenous (∼47% CP) and isolipidic (18.2% L) diets were fed, twice a day, 6 days a week to apparent satiation, to triplicate groups of seabream growers (mean IW, 130.85 g) in PVC tanks. The growth trial lasted for 20 weeks at an average ambient water temperature of 27.0±1.8°C. At the end of the experiment, fish attained market size (300–400 g) and their health status was evaluated by blood analyses, head kidney prints and liver histology. Haemoglobin and haematocrit contents, erythrocyte (RBC) and leucocyte (WBC) count remained significantly unaffected by any dietary treatments. Despite the apparent relatively higher thrombocyte counts for fish fed vegetable oil diets, especially Mix 2 as compared with those of CTR fish, variations were found to be insignificant (P>0.05). However, a slight deformation in erythrocyte shape was noticed in the blood films of fish fed the vegetable oil diets. Inclusion of either dietary vegetable oil blend had also elevated the number of both developing myelocytes and phagocytes in fish head kidney prints examined compared with those of CTR fish particularly for Mix 2 group. Liver from seabream fed vegetable oils showed slightly swelled hepatocytes due to accumulation of oil droplets in the cytoplasm. In the liver sections investigated ultra‐structurally, nuclei and cytoplasmic organelles were shifted towards the cell periphery. Hepatocytes of fish fed Mix 2 diet showed relative shrinkage and picnotic nuclei, compared with those of CTR fish, suggesting an effect on lipid transport and/or metabolism in fish. The comparative hepatic features between experimental fish groups were described. Accordingly, Mix 1 diet (with LO) was considered better than Mix 2 (with BO) in terms of influence on seabream growers' health status. 相似文献
10.
Elham A. Wassef Stavros Chatzifotis Eman M. Sakr Norhan E. Saleh 《Journal Of Applied Aquaculture》2013,25(3):216-229
To improve the unnatural fade-pigmented skin of cultivated gilthead seabream, Sparus aurata, (if shown) the present study was initiated. The effects of either red bell-pepper (Capsicum annum) meal or carrot (Daucus carota) meal as a natural dietary carotenoid source, on growth and skin coloration of gilthead seabream growers were investigated. A basal/control diet (D1/CTR) was firstly formulated to contain 48% crude protein and 14% lipids, with no added-carotenoids. With this basal diet, two other test diets were similarly prepared and supplemented each with about 40mg/Kg total carotenoids from either red-pepper meal (D2) or carrot meal (D3). In a feeding trial, fish (mean IW, 94.86±0.3g) were fed one of the three diets (D1, D2, D3), in triplicates for each treatment, for 6 weeks in light-blue background PVC tanks supplied with natural seawater flow. Total carotenoids content of skin was determined spectrophotometerically at initiation and end of the experiment. Neither growth nor feed utilization were significantly (P<0.05) affected by the red pepper-added diet (D2) as compared to CTR diet. However, the carrot fed fish recorded the lowest and significant (P<0.05) weight gain (g/fish) and specific growth rate (SGR, %/d) among dietary treatments. There were no considerable (P>0.05) differences in major nutrients composition between fish fed the experimental diets. Total carotenoids content was significantly (P<0.05) increased, in the skin-opercle area, of fish fed the red pepper diet (D2) as compared to initial fish and to either carrot fed fish or CTR fish. Results have suggested that gilthead seabream can effectively bio-absorb natural carotenoid pigments (mainly capsansin and capsorbin) in red-pepper but not in carrot (mainly β-and α-carotene). 相似文献