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1.
This experiment was designed to investigate and compare the egg production, fertility, hatchability and immune responses of some local developed Egyptian chicken strains under high ambient temperatures. A total of 108 (26 weeks old) laying hens of Matrouh, Silver Montazah, Mandarah and Inshas (9 hens × 3 replicates × 4 strains) were used to evaluate the impact of thermal stress (24-34ºC) during summer season (June, July and August) on egg production, fertility, hatchability and immune responses. The obtained results revealed that final body weight (FBW/g) and body weight change (BWC/g) among different chicken strains were not affected. The daily feed consumption (FC/g) and feed conversion ratio (FCR) for Silver Montazah and Inshas strains were significantly (p ≤ .05) higher than those of Matrouh and Mandarah strains. The mean egg production (EP/%) and egg mass (EM) for Silver Montazah and Inshas strains were significantly (p ≤ .05) higher than those of Matrouh and Mandarah strains. The highest percentages of hatchability of total eggs (HTE) and fertile eggs (HFE) were recorded in Inshas chickens, while the lowest value was recorded in Mandarah chickens. Also, the highest embryonic mortalities (p ≤ .05) and lowest chick weight at hatch (CWH/g) were recorded in Mandarah chickens compared with the other strains. The highest values for antibody titres against phytohemagglutinin-P (PHA-P) were recorded in Mandarah chickens, while the least values were recorded in Inshas chickens.  相似文献   
2.
The pathogenicities of RacL11 and Kentucky D strains of equine herpesvirus 1 in the hamster infection model are different from those of Ab4p and the Japanese isolates. Virus genome restriction fragment length polymorphism analysis and sequence comparison of an intergenic region, glycoproteins and tegument genes showed higher conservation but with some strain-specific differences. These results indicate that point nucleotide differences in RacL11 and Kentucky D might be responsible for their pathogenicity in rodent models.  相似文献   
3.
The viscosity of the soluble fibre, β-glucan, has been shown to influence its ability to lower serum cholesterol and postprandial blood glucose levels. The impact of various amylases, proteases and lipase on the solubility and resulting viscosity of β-glucan extracted from oat bran cereals with a range of β-glucan concentrations and molecular weights was investigated. Addition of enzymes increased the final viscosity of high molecular weight β-glucan in cereals by facilitating the release of β-glucan from the food matrix. For cereals with partially depolymerized β-glucan, the addition of digestive enzymes decreased the final viscosity by eliminating the contribution of starch and protein to viscosity. Final viscosity varied depending on enzyme combinations including pancreatin, salivary and microbial α-amylases, microbial protease, porcine protease, trypsin and α-chymotrypsin. Addition of lipase did not significantly affect viscosity or solubility of β-glucan extracted from oat crackers. Addition of lichenase showed that β-glucan was the major contributor of viscosity to the system, with negligible interference from other components. The viscosity of the optimized protocol was compared to physiological results previously obtained. The viscosity of β-glucan extracted with pancreatin plus microbial α-amylase (pH 6.9) was predictive of LDL-cholesterol reduction (R2 = 0.847) and glycemic response (R2 = 0.883).  相似文献   
4.
Leather finishing processes using toxic organic solvent based produce volatile organic compounds (VOC), chronic exposure to this chemicals effect on workers' health causing many diseases especially lung cancer. So, polyurethane waterbased was synthesized for application in leather finishing instead of organic solvent based because it’s economic and safety for industry and workers. Preparation of water-based polyurethane (PU) depends on the reaction of polyethylene glycol (PEG, 300) with isophorone diisocyanate (IPDI) and the reaction of IPDI-1,4-butanediol (BDO) together with dimethylolpropionic acid (DMPA), was synthesized by poly-addition polymerization reaction. PU was then modified with different amounts of silicon dioxide nanoparticles (1-5 % SiO2), used as a binder in leather finishing. Leather coated was characterized physically, chemically and thermally by FTIR, GPC, DLS, TEM, SEM and TGA. The results revel that, water vapor permeability (WVP) of leather coated with PU modified with SiO2 showed improvement due to the existence of SiO2 particles which increases the interspaces of the polyurethane coating. SEM showed that when the amount of SiO2 nanoparticles increases, there is uniform nanoparticles accumulated can be observed. EDX prove the presence of Si and O2 elements and the formation of SiO2 nanoparticles. Mechanical properties discussed that tensile strength; tear strength and elongation at break % increase with increase SiO2 concentration until 3 % SiO2 nanoparticles. TGA showed an improvement of thermal stability of coated leather modified with SiO2. Therefore, this study succeeded in preparation of safe, ecofriendly of water-based polyurethane binders which modified with SiO2 for using in leather finishing.  相似文献   
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6.
An experiment was conducted to evaluate semipurified test diets for Tilapia zillii fingerlings. Four isocaloric (300 kcal dietary energy/100 g) diets containing casein (at 30 and 39%). casein supplemented with L-arginine (Arg) and casein/gelatin mixture as protein sources were fed to triplicate groups of T. zillii fingerlings at a daily rate of 3% of their body weight for 6 weeks. When casein was fed as the sole dietary protein source at 30% level, fish growth, feed conversion efficiency (FC) and protein efficiency ratio (PER) were significantly reduced. Those variables were significantly improved when casein was supplemented with Arg. The group of fish fed casein/gelatin diet showed the best growth and feed utilization. When casein was increased to 39% to meet the Arg requirement, fish growth and feed conversion were not significantly different from those of fish fed casein/gelatin diet, while PER and protein production value (PPV) were significantly reduced. These results indicated that casein/gelatin is superior to casein or casein/Arg as a protein source in semipurified test diets for T. zillii fingerlings.  相似文献   
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Objective To determine in Australian pig herds the accuracy of French protocols for risk factor assessment.
Procedure Data on health indicators and risk factors were collected for three syndromes, 'pre-weaning diarrhoea', 'post-weaning diarrhoea' and 'respiratory problems', using the French protocols. The protocols were used on 118 occasions in 32 Western Australian pig herds during 3 years (1988 to 1991).
Results There was a wide variation in pre-weaning performance, for example growth rate was 107 to 273 g/day (< 200 g/day in 33% of herds). Respiratory lesions at weaning were associated with poor pre-weaning performance. Post-weaning (21 days after weaning) growth rate was 114 to 408 g/day (< 250 g/day in 54% of herds). In the grower herds, 91% of herds had pneumonia, and growth rate was 439 to 625 g/day (< 550 g/day in 54% of herds). Pleurisy as well as pneumonia was associated with reduced growth rate. The risk factor most closely associated with respiratory health status was air volume per pig.
Conclusion Risk factors were most accurate at predicting the health status in post-weaning problems. A weaning weight of at least 7.9 kg and weaning age of 30 days optimised weaner performance. Stocking densities and shed designs providing at least 3 m3 air volume and 0.6 m2 floor space per pig throughout the growing phase should be considered for an improved respiratory health status. Australian pig sheds often do not provide a satisfactory environment for optimum health. The technique of risk factor assessment as an aid to the maintenance of health in pig herds is applicable in Australia, but further research is necessary to determine the most important Australian risk factors.  相似文献   
10.
The aerial part of Leptadenia arborea has been shown to contain pinoresinol (1), syringaresinol (2), leucanthemitol (3) and E-ferulaldehyde (4). These known compounds are being reported for the first time from this plant. Among them, syringaresinol has shown an inhibitory effect against acetylcholinesterase. The IC(50) (the concentration of 50% enzyme inhibition) value of this compound was 200 microg/ml.  相似文献   
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