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61.
More than 40% of human food produced is wasted and much of it in restaurants. Two 8‐week feeding experiments were performed to evaluate the suitability of using restaurant food waste to supplement commercial feed (CF) in the aquaculture of Nile tilapia Oreochromis niloticus. In the first experiment, five feeding regimens in which CF was substituted by waste‐based feed at 0, 25, 50, 75 and 100% of daily offering were evaluated. Results show that 25% of the CF can be replaced with waste‐based feed without any significant effect on survival, growth, feed conversion, hepatosomatic, viscerosomatic (VSI) indices, haemoglobin, haematocrit and total plasma protein (TPP). In the second experiment, seven feeding treatments were evaluated in which daily offerings of CF were alternated with waste‐based feed in 6‐day cycles. Results suggest that replacement between 25% and 33% is feasible without significantly affecting survival or growth. Again, no significant differences were observed in growth, feed conversion ratio, VSI, haemoglobin, haematocrit and TPP. Findings suggest that around 25% replacement of CF with Lebanese restaurant waste‐based feed can be utilized in the culture of O. niloticus thus improving financial returns of farmers while reducing the environmental impact of food waste.  相似文献   
62.
The objective of this study was to determine the effects of foliar salicylic acid (SA) on salt tolerance of sweet basil seedlings by examining growth, photosynthetic activity, total osmoregulators, and mineral content under salinity. Salinity treatments were established by adding 0, 60, and 120 mM sodium chloride (NaCl) to a base nutrient solution. The addition of 60 and 120 mM NaCl inhibited the growth, photosynthetic activity, and nutrient uptake of sweet basil seedlings, and increased the electrolyte leakage and the plant contents of proline and Na. Sweet basil seedlings were treated with foliar SA application at different concentrations (0.0, 0.50, and 1.00 mM). Foliar applications of SA led to an increase in the growth, chlorophyll content, and gas exchange attributes. With regard to nutrient content, it can be inferred that foliar SA applications increased almost all nutrient content in leaves of sweet basil plants under salt stress. Generally, the greatest values were obtained from 1.00 mM SA application.  相似文献   
63.
ABSTRACT: Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14) and solvent-extracted soybean meal (n = 5) were obtained from People's Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2) and mechanically extracted (heated) soybean meal (n = 2) from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration when formulating ruminant diets.  相似文献   
64.
Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14) and solvent- extracted soybean meal (n = 5) were obtained from People’s Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2) and mechanically extracted (heated) soybean meal (n = 2) from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration when formulating ruminant diets.  相似文献   
65.
Parentage analysis is of vital importance for hatchery production and breeding programmes. Two multiplex PCR protocols including seven tropical spiny lobster (Panulirus homarus) microsatellites (Pho‐G06, Pho‐G25, Pho‐G53, Pho‐G62, Pho‐G74, Pho‐G89 and Pho‐G100) were introduced for parentage assignment. All loci were polymorphic with allele sizes from 113 to 337 base pairs (bp), observed alleles (k) from two to seven and polymorphic information content (PIC) of 0.25 to 0.73. Twenty‐four stage‐3 phyllosoma larvae (39 days posthatching) were collected for paternity exclusion study using selected microsatellites. Exclusion‐based parentage analysis unambiguously assigned 83% of fry (20 of 24) to a single female parent. Of ten putative female parents, five have contributed to the 20 allocated offspring, with one being true parent of 11. Four others were assigned to two or more potential female parents, probably due to genotyping error or the presence of null allele. The exclusion power (EP) for the seven loci varied between 13% and 54% with known genotypes of one parent (P1) and 19% and 71% for given the genotypes of both parents (P2). The theoretical combined parentage exclusion (cEP) power for all seven microsatellites was P1 = 95% and P2 = 99%. The power of discrimination for each locus varied between 0.18 and 0.86. This report presents the first study to utilize microsatellite markers for successful parentage assignment of P. homarus. The selected microsatellites provide a practical tool for parentage analysis in hatchery production of juveniles as well as in future commercial breeding programme of tropical spiny lobsters.  相似文献   
66.
Herein, a biodegradable and biocompatible composite comprising of support membrane based on crosslinked PVA/PEG film and curcumin loaded electrospun poly(lactic acid) (PLA) nanofiber mat is introduced. The membrane film was prepared from PVA/PEG blend followed by crosslinking with an optimum amount of citric acid, 15 wt.%. After then, PLA solutions with different curcumin content, 0-11 wt.%, were electrospinned on the prepared membrane substrate. The prepared film showed high water absorption, water vapor transmission rate and superior mechanical properties with improved elastic modulus, tensile strength and with an elongation of around 320 % with respect to the non-crosslinked one. Also, the scanning electron microscopy was revealed uniformly dispersed pores throughout the membrane film with a nearly narrow in size distribution centered at 36 μm. As well, a nanostructure porous morphology was found for the electrospun fibrous curcumin loaded PLA from the scanning electron microscopy micrographs and the average fiber diameter was decreased with curcumin content. In vitro drug release from the prepared flexible composite into the vertical diffusion cell was recorded by the measuring curcuminoids content using high performance liquid chromatography and drug release kinetic evaluations were revealed that the release pattern of all prepared samples, containing different content of curcumin, well fitted to the Higuchi’s model signifying diffusion-controlled release mechanism. As well, the determined release rate at the second release stages, i.e. steady state flux (J), was varied from 0.31 to 43.53 μg·cm-2·h-1 with increasing drug content from 1 to 11 wt.%. Regarding this results, this flexible composite by providing the moist environment along with miraculous healing properties of curcumin, can be potential candidate for transdermal drug delivery.  相似文献   
67.
In this study, central composite design (CCD) based on response surface methodology (RSM) was employed to optimize parameters of melt-spinning process of poly(ethylene terephthalate) partially oriented multifilament yarn (POMFY). On the basis of a four-variable CCD, RSM was used to determine the effects of spinning temperature, spinning pressure, take-up velocity and quenching air velocity on the levels of the elongation of POMFY as the response. The POMFY samples were also characterized by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. By applying a quadratic regression analysis, an equation indicating the effect of each variables on the response was developed. The predicted values of the parameters showed excellent agreement with the experimental values (R 2=0.9565, Adjusted-R 2=0.916). Moreover, the results confirmed that the CCD mathematical model was a suitable method to optimize the melt-spinning parameters of POMFY in an industrial scale.  相似文献   
68.
69.
As aquaculture evolves from extensive pond culture to intensive tank and cage systems, chemical dips and baths are increasingly being used to treat a concomitant increase in ectoparasitic and bacterial infestations. Some of the main disease‐causing agents are ectoparasites on the skin and gills of fish. Consequently, application of chemotherapeutics is increasing in aquaculture industries in order to control outbreaks of parasitic infestations. However, the toxic effect of commonly used chemotherapeutic agents on specific aquacultured fish species is often unknown. The present work was performed to test the effect of four commonly used chemical treatments on rabbitfish, Siganus rivulatus. The lethal concentrations for 50% of population (LC50) of formalin, copper sulfate, potassium permanganate, and hydrogen peroxide for S. rivulatus juveniles treated for 1 h were assessed. Formalin and potassium permanganate tolerance values were determined by calculating 72‐h LC50 values through probit analysis. The 72‐h LC50 values for the formalin toxicity tests were 551.0 and 1.68 mg/L, respectively. LC50 of copper sulfate and hydrogen peroxide could not be determined from the concentrations tested but were found to be >3 and >700 mg/L, respectively. Accordingly, treatment concentrations of formalin and potassium permanganate used for other fish species could be lethal to S. rivulatus, but the species appears to be quite tolerant to copper sulfate and hydrogen peroxide.  相似文献   
70.
In this study, we developed new method to prepare one-pot current collector/electrode plate to be utilized in the fuel cell technology. In situ preparation of zero-valent N-doped Co carbon nanofibers (Co/N-CNFs) as an immobilized thin film onto graphite disc was achieved by electrospinning technique, followed by calcination at 1100 oC in argon atmosphere. This catalyst was used for methanol electrooxidation in alkaline media. The effects of nitrogen doping and immobilization on the activity and stability of the prepared catalysts were studied using cyclic voltammetry and chronoamperometry, respectively. SEM, TEM, EDX, XRD, and TGA were used to characterize the morphology and composition of Co/N-CNFs catalysts. The results showed that the electrocatalytic activity as well as the stability of Co/N-CNFs towards methanol electrooxidation in alkaline media were significantly affected by both nitrogen doping and immobilization of the catalyst on the graphite disc. Moreover, the methanol concentration has also affected the electrocatalytic activity of Co/N-CNFs-supported immobilized onto graphite disc and Co/N-CNFs-unsupported graphite disc.  相似文献   
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