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41.
The functional properties of wheat powders depend largely on the surface characteristics of their particles. X-ray photoelectron spectroscopy (XPS) has been considered to investigate the surface composition of wheat powders. The objective of the present study is to evaluate the ability of XPS to discriminate wheat components and to calculate the surface composition of wheat powders. First, XPS surveys for the main wheat isolated components (starch, proteins, arabinoxylans, and lipids) were determined. XPS results demonstrate that it is able to distinguish wheat proteins, polysaccharides, and lipids, but it is not able to distinguish starch and arabinoxylan because of their similarity in chemical structure. The XPS analyses of simple reconstituted wheat flours based on two components (starch and protein) or three components (by adding arabinoxylan) demonstrated the ability of XPS to measure the surface composition of the wheat flours. The surface composition of native wheat flour demonstrated an overrepresentation of protein (54%) and lipids (44%) and an underrepresentation of starch (2%) compared to the bulk composition. Results are discussed with regard to difficulties in discriminating arabinoxylans and starch components.  相似文献   
42.
Twelve pelleted diets containing a range of protein and energy levels from 30% protein, 400 kcal gross energy per 100 g diet to 40% protein and 520 kcal gross energy per 100 g diet were formulated. A least-cost linear programming package was applied to determine the optimum inclusion levels of some locally available ingredients. The essential amino acid constraints applied to the diets were based on the essential amino acid content of the eggs of broodstock Macrobrachium rosenbergii (de Man). The study was undertaken using 13 one-tonne capacity fibreglass tanks, each with a water recycling system. Each tank was partitioned into three equal compartments by nylon netting; each compartment was stocked with six female and one male prawn which were fed with the various diets at 2% body weight daily split into three feedings at 0800, 1200 and 1800 h. The results indicated that prawn fed the 40% protein diet with an energy level of 400 kcal per 100 g diet attained the highest fecundity, producing 1355 eggs per gram body weight, followed by those fed P40 with a gross energy level of 440 kcal 100 g-1 (1354 eggs per gram body weight), and prawns fed control diet (30% protein with an energy level of 442 kcal 100 g diet-1) attained the lowest fecundity (1080 eggs per gram body weight). However, statistically, no significant differences in fecundity were observed among prawn fed 35% protein diet with an energy level of 473 kcal 100 g-1, 40 with energy levels of 400 or 440 kcal 100 g diet-1. The essential amino acids index (EAAI) were calculated and were found to be a possible method of evaluating the broodstock diet of M. rosenbergii as a higher index indicates higher egg production. Therefore, a diet containing 40% protein, with an energy level of 400 kcal 100 g diet-1 is recommended as a broodstock feed for M. rosenbergii in view of its superior performance and cost.  相似文献   
43.
The efficiency of indirect haemagglutination (IHA) and immunoelectrophoresis (IEP) as means of detection of cystic hydatid infection in camels was investigated. Both IHA and IEP showed very low detection rates of antibody in camel sera. The IEP showed 84 p. 100 specificity and 36 p. 100 sensitivity while the IHA showed 69 p. 100 specificity and 43 p. 100 sensitivity. These results are discussed.  相似文献   
44.
Bacterial growth (E. coli) in whey was studied by turbidometric technique during estradiol benzoate administration (0.02 mg/kg of body weight/day for 12-19 days) to 13 ovariectomized cows at three stages (early, mid and late) of the 1st- and 3rd-lactations. Whey samples from cows at early stage (60-90 days) of 1st-lactation promote the growth of E. coli during the estradiol treatment. This included a significant increase in the maximum turbidity and a decrease in the generation time. Bacterial growth was inhibited in whey from cows at other stages of lactation during the hormone treatment. The degree of inhibition varied at different stages of lactation. No significant alterations in the ability of whey to support bacterial growth were observed in 3 ovariectomized cows treated with the drug vehicle (arachis oil) alone. Majority of the quarters included in the present study were bacteriologically negative throughout the study.  相似文献   
45.
Infectious bronchitis virus (IBV) causes respiratory disease in chickens all over the world. IBV has many serotypes that do not confer cross protection against each other. Hemagglutination inhibition (HI) test has been used to determine the serotypes of IBV as a substitute to the more laborious virus neutralization test and the more sophisticated restriction endonuclease digestion or sequencing of the S1 gene. In Jordan, no previous studies have been carried out to determine the involvement of IBV in respiratory disease in chickens, or the serotypes of IBV that possibly exist. In this study, serum from different chicken flocks (n = 20) that suffered from respiratory disease were tested for IBV antibodies using commercial IBV antibody ELISA at time of the initial signs of the respiratory disease and repeated on serum samples from the same flocks 10–14 days later. ELISA titer for IBV increased in 14 out of 20 flocks (70%) after 10–14 days of the initial signs of the respiratory disease and this indicates a recent exposure to IBV. The second serum samples from these 14 flocks were further examined against a panel of five IBV antigens (Ark, Conn, DE-072, JMK, and Mass) by HI test to determine the serotype(s) of IBV they have been exposed to. The HI test results indicated that the exposure of some of these flocks were to Ark, DE-072, and Mass like serotypes. However, the HI titers against the antigens used in this study were relatively similar in 10 out of the 14 flocks (71%) and the serotype of IBV that these flocks were exposed to could not be determined and the possible causes of this are discussed.  相似文献   
46.
Genetic Resources and Crop Evolution - Soybean is a high-nutritional crop that provides a sustainable source of dietary protein and edible oil for human consumption and animal diet. In this...  相似文献   
47.
European Journal of Plant Pathology - A study of the effect of bioagents and dipotassium phosphate (DPP) and their combination on early blight disease reduction under greenhouse conditions was...  相似文献   
48.
Specific AFM analytical methods were tested to the surface evaluation of wheat powders at micrometric scale in dry conditions. The objective was to evaluate the adhesion properties of particles based on the main wheat endosperm components (starch, protein, and arabinoxylan) that are characterized by large diversity in terms of chemical composition and particle characteristics. Experiments were conducted by using the force spectroscopy mode to determine interactions generated by the surfaces of particles that were glued on AFM tips, and two reference flat and smooth surfaces, a glass and a polysine slide. Particular care has been devoted to characterize the surfaces in contact since local contact radius is a key parameter in the interpretation of the interactions. The statistical analysis of the normalized adhesion forces have shown the sensitivity of the AFM technique for hydrophobic wheat components and their correlation with the surface tension of the particles.  相似文献   
49.
This experiment was carried out to investigate the potential probiotic properties of Bacillus subtilis and suitable methods of administration to the commercial feed in juvenile Macrobrachium rosenbergii (de Man) from 25 August to 25 November 2008. Putative Bacillus subtilis bacterium isolated from juvenile M. rosenbergii intestine was added to commercial prawn feed as a probiotic. Five types of diets were prepared by mixing B. subtilis at level of 108 cells g?1 with commercial feed using different methods consisting mixing, soaking, spraying and bathing. After 60?days, the prawns fed diets at soaking method treated group, showed a higher mean weight gain (2.09) or 328.84% increase in growth over control. There were significant differences (P?<?0.05) in weight gain, feed intake and FCR among soaking method and other treated and control groups. There was significant difference (P?<?0.05) in survival among treated and control groups, but no significant difference (P?>?0.05) in water quality and biochemical composition among treated and control groups. Clearly, B. subtilis-treated diets appeared to enhance growth and survival of juveniles M. rosenbergii. It was concluded that the tested strain may be a promising probiotic for M. rosenbergii under soaking method of administration to the prawn commercial feed.  相似文献   
50.
This research involved testing the replacement of corn gluten protein concentrate in the diet of 1.5 g Nile tilapia with biofuel algae‐based or algae supplemented with phosphorus diets. Experimental diets were formulated to replace 50% of the gluten meal protein in the control diet with biofuel algae protein (Alga50) or Spirulina (Spirulina50) protein. In addition, dicalcium phosphate (P) was added to the Alga50 at a concentration of 3.8% or 7.74% to mitigate aluminium (Al) toxicity and designated as Alga50 + P, and Alga50 + PP respectively. After 9 weeks of the feeding experiment, fish fed diets supplemented with P, Alga50 + P and Alga50 + PP differed significantly (< 0.05) with respect to the feed conversion and protein deposition from the control. The mineral composition of the fish body showed a decrease in levels of Al and iron (Fe) due to the P supplements. The mineral composition of the faeces indicated that Al and Fe were excreted in the faeces and were not accumulated in the fish body. The effect of dicalcium P supplementation on the neutralization of Al in the diet resulted in improved fish growth and histological integrity of the gastrointestinal tract.  相似文献   
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