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131.
Red sea bream Pagrus major (RSB) weighing 0.09 g were fed on test diets, composed of 65% fish meal supplemented with 0.49% Crataegi fructus (Cf) and a mixture of Massa medicata, Cf, Artemisia capillaries and Cnidium officinale (HM) or a control diet without herbs, in trial 1. After air exposure and anaesthesia treatment, higher stress tolerances were obtained in herbal groups than control group. Moreover, after challenge test with Vibrio anguillarum, mortalities of the herbal groups were lower than the control group. There was no significant difference in growth performance among the treatments. Feed efficiency (FE) of the test groups was 124–141%. In trial 2, RSB weighing 0.11 g were fed on diets composed of 35% fish meal and 30% enzyme treated fish meal (EFM) with the same herbal treatments as trial 1. The herbal groups revealed higher final body weight and specific growth rate (SGR) and lower daily feed intake than those of the control group. The FE of test groups was 172–203%. These results indicate that the dietary herbs supplementation acts not only as recovery enhancer for some rearing stresses but also as growth enhancer, which is accelerated with dietary EFM in the early juvenile stage of red sea bream.  相似文献   
132.
ABSTRACT

A 30-day experiment was conducted to assess the effect of tryptophan-supplemented diets on growth and survival of Pabda, Ompok bimaculatus fry. Fifty pabda fry (0.114 ± 0.02 g; 2.45 ± 0.13 cm) were stocked into each aerated aquarium following a completely randomized design consisting of four treatments with triplicate each. Four iso-proteinious purified diets were prepared with different levels of tryptophan—0%, 1%, 2%, and 3%—of the dry diet and were designated as Control, TRP1, TRP2, and TRP3 respectively. Fishes were fed with the experimental diet ad libitum four times a day. The results showed that fish fed with tryptophan-supplemented diets exhibited significantly (P < 0.05) lower cannibalism and higher survival than the control diet. Further, the tryptophan-supplemented groups showed a significantly lower coefficient of variation (%) and size heterogeneity (P < 0.05). However, the growth as measured by body weight gain, length increment, and specific growth rate of fry in tryptophan-supplemented groups was significantly lower than the control group (P < 0.05). Moreover, maximum survival (52.67 ± 1.76%) and minimum cannibalism (21.33 ± 5.70%) coupled with higher growth and performance index (0.38 ± 0.01) were recorded in the 2% tryptophan-supplemented group compared to other tryptophan-fed groups. Overall interpretation from the present study concludes that the dietary supplementation of 2% tryptophan is recommended for better survival of pabda fish, although growth was compromised.  相似文献   
133.
With the objective to develop an indoor tank seed rearing system for pearlspot (Etroplus suratensis), effects of three stocking densities in presence or absence of soil base were evaluated on growth, weight variation, survival and body composition in a 60‐day trial. The experiment had a 3 × 2 factorial design with three levels of stocking density (150, 300 and 450 fish m?3) and two levels of soil base (with and without) in triplicates. Pearlspot fry (27.5 ± 0.5 mm/0.39 ± 0.02 g) were stocked in experimental tanks (Length×Breadth×Height: 0.65 × 0.50 × 0.48 m) and fed with a formulated diet containing 29.85% crude protein. Increasing the stocking density from 150 to 450 fish m?3 significantly decreased the growth (average body weight and total length), daily weight gain, specific growth rate and survival (P < 0.001) and increased the feed conversion ratio (P < 0.01). Significantly lower growth and survival were observed in treatment having soil base compared with that of without soil base (P < 0.001). However, coefficients of variation at harvest weight and body composition of fingerlings were independent to stocking density and presence or absence of soil base (P > 0.05). A significant positive interaction effect of stocking density and presence or absence of soil base was observed on average body weight (P < 0.05) and survival (P < 0.001) of pearlspot fingerlings. This study suggests that stocking density of 150 fish m?3 without soil base in tanks would be appropriate for raising pearlspot fingerlings in brackishwater indoor seed rearing system.  相似文献   
134.
135.
We are reporting for the first time that the catecholamines (adrenaline and noradrenaline) inhibit the effect of nitric oxide (NO) on melanosome dispersion in freshly isolated scales of the freshwater snakehead fish, Channa punctatus. We studied the effect of NO and catecholamines on the pigment displacement by observing the changes in the melanophore index. The scales when treated with solution containing NO donor sodium nitroprusside (SNP) showed dispersion of melanosomes, whereas NO synthase blocker N-omega-Nitro-l-arginine suppresses this action of SNP. Treatment with adrenaline and noradrenaline on the isolated scales caused aggregation of melanosomes. Scales treated with solution containing catecholamines and SNP resulted in aggregation of melanosomes suggesting that catecholamines mask the effect of SNP. These results suggest that the catecholamines are inhibiting the effect of NO and causing the aggregation of the melanosomes may be via surface receptors.  相似文献   
136.
Attempts were made to identify the association between water quality parameters and the presence of Streptococcus agalactiae in cage cultured red hybrid tilapia, Oreochromis niloticus × O. mossambicus. Fish from commercial floating net cage‐culture systems in a river and lake were randomly sampled over a 24‐month period. Swabs from the brains, eyes and kidneys were streaked directly onto blood agar to isolate S. agalactiae. Water temperature, dissolved oxygen, pH, clarity, ammonia, nitrite, sulfide, rate of water flow and depth of water at sampling sites were measured at the same time of fish sampling. The prevalence of fish that were cultured positive to S. agalactiae was significantly higher in lake compared with river. The length and weight of the infected fish were between 9 and 33 cm, and between 20 and 760 g respectively. There was a significant and positive strong correlation between the presence of S. agalactiae and fish mortalities in lake. All water quality parameters showed significant differences between river and lake. However, only water temperature, clarity and pH of lake and the ammonia, temperature and dissolved oxygen in river showed significant correlation with the presence of S. agalactiae in the cultured fish. It was concluded that several unfavourable water quality in the fish farm influencing the presence of S. agalactiae in cultured red hybrid tilapia.  相似文献   
137.
A liquid nitrogen (N2) adsorption isotherm was employed to understand the differential pore-volume distribution (PVD) patterns of commercial Clinoptilolite (zeolite) fractions (<125 µ (Z8; fine or micro), 125–250 µ (Z9; medium) and >250 µ (Z10; coarse). The differential PVD of the fractions were calculated from the original Horvath-Kawazoe (HK) model. A full spectrum of pore volume distribution has exhibited “curves symmetric around the origin” irrespective of the Clinoptilolite fractions. However, the fractions exhibited a definite pattern of curves for each of the micro, meso and macropore region. Although, ultramicropores couldn’t be seen in any of the fractions, super micropore region exhibited uni-modal distribution curve with mono-disperse pores for all the fractions with varying pore volumes, while multimodal and tri-modal for meso and macro pore region respectively. Irrespective of the pore region, fine fraction (Z8) exhibited higher differential pore volume than other fractions. It was evident from the differential PVD that particle size has a major role in determining the textural properties of Clinoptilolite fractions.  相似文献   
138.
A simple and effective method for impregnation of p-aramid (Kevlar®) fabric with shear thickening fluid (STF) has been developed in this research. Kevlar fabric was impregnated with STF in two stages in a sequential manner. Three levels of pressure (0.5, 1 and 2 bar) were used in each stage of impregnation. It was observed that impact energy absorption by Kevlar fabrics, impregnated with STF in this newly developed method, increased significantly as compared to untreated Kevlar fabrics and Kevlar fabrics treated with STF in conventional way (single step impregnation). Better results were obtained when the first impregnation pressure was higher than that of the second, even with same combination of pressures. Such fabrics also showed a much higher STF add-on (~18 %) as compared to that of fabrics impregnated in single step (3-5 %). Low velocity ballistic tests also confirmed the advantages of the new method as sequentially impregnated fabric showed 124.8 % and 24.4 % increase in impact energy absorption compared to untreated and STF impregnated Kevlar fabrics in single step, respectively.  相似文献   
139.
Soil samples were collected and analyzed from 25 sites of three hilly regions (Rangamati, Banderban and Khagrachari) for an understanding of the impact of denudation and land use on soils in Chittagong Hill Tracts, Bangladesh. There were natural forests, bushy land, slashed sites, slashed and burnt sites, and the sites prepared for shifting cultivation, one year after shifting cultivation and two years after shifting cultivation. The soils were generally yellowish brown to reddish brown, sandy to sandy clay loam, strongly acid, and well to excessively drained on steep slopes with considerable variation among the sites and land use categories. Bulk density was the highest in sites of one year after shifting cultivation (1.52 g·cm-3) and the lowest in forested sites (1.38 g·cm-3). Water holding capacities were, however, statistically similar in all sites. Organic carbon varied from 0.54% (slashed and burnt sites) to 1.55% (forested sites) and total N ranged from 0.05% (shifting cultivation for one year) to 0.13% (forested sites). Available phosphorus (Bray & Kurtz-2 P) was the maximum in forested sites (12.32 mg·kg-1), and it did not differ significantly in other sites. Contents of available Ca, Mg and K were also higher in the bushy lands and forested sites than cleared and shifting cultivated sites.  相似文献   
140.
A study was conducted at the experimental farm of Faculty of Agriculture, Ain Shams University, Cairo, Egypt, during two successive summer seasons (2014 and 2015) to investigate the effects of arbuscular mycorrhizal fungi (Glomus irradicans 10% w/w), Bacillus megaterium (10?ml/pot) and brassinosteroids (24-EBL, C28H48O6; 2?µM) on growth, nutrient absorption, chlorophyll, proline content, antioxidant enzymes activity and fruit yield of sweet pepper plants (Capsicum annuum L.) cv. Marconi. Plants were grown under three levels of salinity (0, 25 and 50?mM). The obtained results showed that plants grown under non-saline water (0?mM NaCl), with or without treatments, significantly gave the most vigorous vegetative growth and had the highest fruit yield compared with those grown under salt stress conditions. All anti-salinity treatments (Mycorrhiza, Bacillus and Brassinosteroids) improved growth when compared with untreated plants (control). Plants inoculated with mycorrhiza or treated with brassinosteroids showed better vegetative growth and shoot biomass (total fresh and dry weight per plant), chlorophyll a and b concentrations, antioxidant content expressed as total soluble phenols and proline concentrations at all studied salinity levels followed by plants inoculated with Bacillus megaterium compared with control plants which showed severe growth retardant especially under higher salt concentration (50?mM). Carotenoids concentration increased proportionally with the increase of salinity concentration. The maximum leaf relative water content (LRWC) and lowest values of membrane permeability (MP) were significantly observed with mychorhiza inoculated plants and brassinosteroid application respectively, followed by Bacillus inoculated plants. Antioxidant enzyme activity were highest in plants irrigated with moderate saline water (25?mM) than plants under high salinity irrigation water (50?mM) except polyphenol oxidase (PPO) as compared with unstressed plants (0?mM). Mycorrhizal inoculated plants accumulated higher K and lower Na and Cl followed by plants treated with brassinosteroids and then plants inoculated with Bacillus megaterium. Anti-salinity treatments positively enhanced fruit yield of sweet pepper plants under all salinity stress levels and the highest fruit yield were significantly observed with brassinosteroid application followed by mychorhiza inoculated plants and then Bacillus inoculated plants.  相似文献   
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