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71.
Influence of Stocking Density on Growth and Physiological Responses of Beluga,Huso huso (Brandt, 1869), and Ship Sturgeon,Acipenser nudiventris (Lovetsky, 1828), Juveniles in a Flow‐through System
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Mohammad Yooneszadeh Feshalami Farokh Amiri Mansour Nikpey Seyed Abdolsaheb Mortazavizadeh Enric Gisbert Mansour Torfi Mozanzadeh 《Journal of the World Aquaculture Society》2017,48(4):611-622
The influence of three different initial stocking densities (low stocking density [LSD] = 1.5 kg/m2; medium stocking density [MSD] = 3 kg/m2; and high stocking density [HSD] = 6 kg/m2) in flow‐through systems was evaluated on growth and welfare in beluga, Huso huso, and ship sturgeon, Acipenser nudiventris, juveniles for 2 mo. Fish were kept in 18 concrete square tanks (2.0 × 1.0 × 1.2 m3) at 22.3 ± 0.4 C and under a natural photoperiod. In both species, the growth performance in terms of final body weight, weight gain, specific growth rate, and feed intake significantly decreased with increasing stocking density (P < 0.05). In both species, the percent of neutrophils increased after 60 d of trial (P < 0.05). Moreover, hematocrit and white blood cell counts increased after 60 d of trial in ship sturgeon (P < 0.05). Plasma immunoglobulin significantly decreased with increasing stocking density in both species. Plasma insulin‐like growth factor I decreased with increasing stocking density in beluga; however, it was not affected in ship sturgeon. Overall, these results showed that the LSD group in both species demonstrated more homogeneous and higher growth rate than the MSD and HSD groups. 相似文献
72.
73.
In this work, water-extraction of Vitis Vinifera L. (Black Grenache) leaves and analysis of aqueous extracts for anthocyanins were investigated. Vegetable leaves were cultivated in North of Tunisia at different dates. Anthocyanins were identified as main constituents in these natural dyeing materials using high performance liquid chromatography (HPCL). Dyeability of wool and its fastness properties using Vitis Vinifera L. leaves extract were also determined. Aqueous extract of Vitis Vinifera L. leaves has markedly yielded shades with good fastness properties. Thus, affordability is a point favorable for Vitis Vinifera L. leaves. Effects of dye bath pH and temperature on dyeability and fastness proprieties of wool fabrics by aqueous extract of Vitis Vinifera L. leaves were evaluated. Experimental results showed that fastness properties of dyed fabrics ranged from average to very good. Vitis Vinifera L. leaves extracts showed potential to dyeing wool fibers under highly acidic conditions (pH ≤2). The results obtained here revealed that natural dyes extracted from Vitis Vinifera L. leaves can be cost-effective for dyeing wool fabrics. 相似文献
74.
Yasser Trabelsi Foued Gharbi Abdessalem El Ghali Mansour Oueslati Mohammad Samaali Wahid Abdelli Souad Baccouche Malik Ben Tekaya Moncef Benmansour Lionel Mabit Nabiha Ben M’Barek Nafaa Reguigui Jose M. Abril 《Journal of Soils and Sediments》2012,12(5):784-796
Purpose
Ichkeul National Park, NW Tunisia, is a UNESCO Biosphere Reserve. Garaet El Ichkeul Lake is known for its seasonal variability in water level and salinity. In recent decades, the waterbody has been affected by the construction of new hydraulic structures. To reduce the impacts of dams and to maintain the sustainability of the ecosystem, a sluice was built at the outlet of the lake, and it operated for the first time in 1996. This paper describes an investigation of recent sedimentation dynamics in Ichkeul Lake, determined by radiometric dating of sediment cores.Materials and methods
A sediment core was collected with a UWITEC gravity corer at the deepest, central part of the lake in August 2009. Specific activities of unsupported lead-210 (210Pb) and caesium-137 (137Cs) were measured in the core, enabling calculation of recent sediment accumulation rates (SAR). Published radiometric data from nearby sediment cores, collected in 1997 and 1982, provide a comparison.Results and discussion
The measured excess 210Pb inventory was 5300?±?500?Bq?m?2, leading to an estimation of constant flux of 165?±?16?Bq?m?2?yr?1, a value higher than the best estimate for local atmospheric fluxes (123?±?12?Bq?m?2?yr?1) and the flux estimated from the core collected in 1982 (48?Bq?m?2?yr?1). The 137Cs inventory was 3550?±?120?Bq?m?2, two times higher than the historical 137Cs atmospheric deposition in the area. The 137Cs profile displayed a distinct peak, but the 137Cs depth-distribution did not follow the pattern expected from atmospheric deposition. Application of the constant rate of supply (CRS) model, with the reference point method, produced a chronology and SAR values comparable to those found in previous work. The whole 137Cs profile was quantitatively reconstructed from the historical records of atmospheric deposition, using the system-time-averaged (STA) model.Conclusions
The CRS and STA models provide consistent sediment accumulation results for the whole data set, considering the time resolution of the chronology (~6?years) and analytical uncertainties. Results from cores sampled in 1982, 1997 and 2009 reveal an increasing SAR trend, from ~0.25?g?cm?2?yr?1 in the early 1940s to ~0.67?g?cm?2?yr?1 at present. In the 13?years since installation of sluice gates at Tinja, SAR in the central Ichkeul Lake has not declined. Thus, if siltation continues at the present rate, shallowing of the lake will seriously affect the hydromorphology and ecology of this important lake. 相似文献75.
E. H. Mansour 《Plant foods for human nutrition (Dordrecht, Netherlands)》1996,49(4):271-282
The effects of germination, extraction (double extraction with 70% ethanol and water at isoelectric point) and -amylase treatments of chick pea seed flours on crude protein, total carbohydrate, protein efficiency ratio (PER), biological value (BV), true digestibility (TD), net protein utilization (NPU), essential amino acid composition, in-vitro protein digestibility (IVPD) and actual amino acid indices (essential amino acid index or amino acid score) were evaluated. Crude protein content was increased (8–149%), while total carbohydrate was decreased (11–62%) by germination, extraction and -amylase treatments. Alpha-amylase treatment was more efficient in reducing total carbohydrate and increasing the protein content than that of extraction treatment. The protein quality of chick pea flours as measured by PER, BV, TD, NPU, IVPD and corrected amino acid indices (actual amino acid indices×IVPD) was significantly improved by these treatments. The protein quality of germinated--amylase treatment was comparble with casein, while germinated--amylase treaded seeds appeared nutritionally superior to casein. The results indicate that the germinated--amylase and germinated--amylase-extracted treatments could be used successfully as a source of concentrated high quality protein for baby food production. The corrected amino acid indices gave better prediction of PER, BV, TD and NPU (r=93 to 97) than actual amino acid indices (r=45 to 71). PER was highly correlated with corrected amino acid score (r=0.93). The PER could be predicted from the following simple regression equation: PER=–1.827+0.0561×corrected amino acid score. 相似文献
76.
The southwestern Iran is one of the regions that are most prone to dust events.The objective of this study is the analysis of the spatial and temporal distributions of dust deposition rate as a key factor for finding the relative impact of the dust.First,the monthly mean aerosol optical thickness(AOT)from Moderate Resolution Imaging Spectroradiometer(MODIS)was analyzed and compared with the dust amount variations from ground deposition rate(GDR),and the results were further used to investigate the spatial and temporal distributions of dust events in southwestern Iran for the period between 2014 and 2015.Moving air mass trajectories,using the Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model,were proven to be a discriminator of their local and regional origin.The results from GDR analysis produced a correlation coefficient between dust event history and deposition rates at dust magnitudes of>0.93 that is meaningful at the 95%confidence level.Furthermore,the deposition rates varied from 3 g/m2 per month in summer to 10 g/m2 per month in spring and gave insight into the transport direction of the dust.Within the same time series,AOT correspondences with MODIS on Terra in four aerosol thickness layers(clean,thin,thick,and strong thick)were shown in relation to each other.The deepest mixed layers were observed in spring and summer with a thickness of approximately 3500 m above ground level in the study area.Investigations of ground-based observations were correlated with the same variations for each aerosol thickness layer from MODIS images and they can be applied to discriminate layers of aeolian dust from layers of other aerosols.Together,dust distribution plots from AOT participated to enhance mass calculations and estimation deposition rates from the thick and strong thick aerosol thickness layers using the results from GDR.Despite all the advances of AOT,under certain circumstances,ground-based observations are better able to represent aerosol conditions over the study area,which were tested in southwestern Iran,even though the low number of observations is a commonly acknowledged drawback of GDR. 相似文献
77.
Differences in susceptibility to the myxozoan parasite Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease (PKD), between four strains of rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta) were evaluated. Fish were exposed to water enzootic for the parasite in the field for 5 days and were subsequently transferred to the laboratory. Relative parasite load was determined after 2, 3 and 4 weeks post-exposure (wpe) by quantitative real-time PCR (qPCR) of kidney samples and number of parasite stages was determined in immunohistochemical stained sections of kidney, liver and spleen tissues. According to qPCR results, the highest amount of parasite DNA per equal amount of host tissue at all time points was measured in brown trout. Two of the rainbow trout strains showed lower relative parasite load than all other groups at the beginning of the experiment, but the parasite multiplied faster in these strains resulting in an equal level of relative parasite load for all rainbow trout strains at 4 wpe. A weak negative correlation of fish size and parasite load was detected. Only in samples of a few fish, single stages of T. bryosalmonae were found in sections stained by immunohistochemistry impeding quantitative evaluation of parasite numbers by this method. The results indicate a differential resistance to T. bryosalmonae between the rainbow trout strains investigated and between rainbow trout and brown trout. 相似文献
78.
Pompeo Suma Ramzi Mansour Agatino Russo Ivan La Torre Abdalbaset Abusalah Ali Bugila José Carlos Franco 《Phytoparasitica》2012,40(1):11-16
Laboratory studies assessing the degree of suitability of the mealybugs Planococcus ficus (Signoret), Planococcus citri (Risso) and Pseudococcus calceolariae (Maskell), towards the Sicilian ecotype of the encyrtid parasitoid Anagyrus sp. nr. pseudococci were carried out. All three species of mealybugs were shown to encapsulate the eggs of the encyrtid; however, significant
differences were revealed among them in rates of encapsulation and/or superparasitism. The level of aggregate encapsulation
and effective encapsulation of the parasitoid eggs by P. citri (74.95 ± 0.87 and 60.19 ± 1.70, respectively) was significantly higher than that recorded for P. ficus (aggregate encapsulation = 58.43 ± 0.83 and effective encapsulation = 31.31 ± 1.55) and significantly lower than the values
found in Ps. calceolariae (93.99 ± 0.97 and 88.61 ± 2.03, respectively). As such, rates of parasitism were significantly lower for P. ficus compared with both P. citri and Ps. calceolariae. The two latter species of mealybugs showed similar rates of parasitism by A. sp. nr. pseudococci. Moreover, a significantly higher rate of superparasitism was found for Ps. calceolariae compared with both P. citri and P. ficus, whereas no significant differences were found between the two species of Planococcus for this parameter. 相似文献
79.
Sources of resistance to tomato-yellow-leaf-curl-virus (TYLCV) in Lycopersicon species 总被引:2,自引:0,他引:2
Summary Sources of resistance to tomato-yellow-leaf-curl-virus (TYLCV) were investigated in 16 accessions of three Lycopersicon species and 55 commercial tomato hybrids and cultivars. All commercial hybrids and cultivars were highly susceptible. Accessions of L. hirsutum, L. hirsutum f. glabaratum and L. pimpinellifolium showed a wide range of reactions. Those of L. peruvianum, LA 385 of L. peruvianum f. humifusum exhibited very high levels of resistance indicating their potential use in local breeding programs. In contrast to earlier findings, back indexing showed that all symptomless genotypes in this investigation were carriers of the TYLCV. 相似文献
80.
M M Mansour J B Dixon T G Rowan S D Carter 《Veterinary immunology and immunopathology》1992,33(3):261-269
The effects of Ostertagia ostertagi infection and diet on antibody responses to O. ostertagi third stage larval (L3) antigen and to an unrelated antigen, Keyhole Limpet Haemocyanin (KLH) were determined in calves experimentally infected with 3000 L3 on alternate days for 6 weeks. Calves were given one of two diets, and were either infected or not infected with O. ostertagi L3. The diets were either high (H) or low (L) in protein/energy and were within the range of normal husbandry practice in the UK. Both IgG1 and IgG2, but not IgA, responses to L3 antigen were increased in the L-diet compared with the H-diet. IgA responses to L3 antigen were not affected by dietary treatment. The effects of diet and infection on anti-KLH IgG1 were independent of each other; IgG1 anti-KLH responses were decreased by infection and by the L-diet compared with the H-diet. The data suggest that there is a strong interrelationship between diet and immunity during nematode infections. 相似文献