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141.
T. Ahmad T. Mushtaq M. A. Khan M. E. Babar M. Yousaf Z. U. Hasan Z. Kamran 《Journal of animal physiology and animal nutrition》2009,93(5):613-621
A 6‐week feeding trial was conducted to determine the effects of varying dietary electrolyte balance (DEB) on growth performance and physiological responses in broiler chicks reared during hot summer months (26.1–37.5 °C). The average minimum and maximum room temperatures recorded from 14 to 42 days of age were 26.1 and 37.5 °C, respectively, with relative humidity ranging from 51% to 55%. Five DEB treatments supplying 0, 50, 150, 250 and 350 (Na++K+–Cl?) mEq/kg of diet were prepared by adding NaHCO3 and/or NH4Cl to basal diet that contained 185 mEq/kg from 1 to 28 days and 172 mEq/kg from 29 to 42 days. These DEB diets were randomly offered to six experimental units of 20 chicks each. Improved 42‐day body weight gain (BWG), feed:gain (F:G) and reduced mortality was noted with DEB 50, 150 and 250 mEq/kg compared to DEB 0 and 350 mEq/kg. A quadratic effect of increasing DEB level was observed on BWG and F:G, whereas the effect was linear for feed intake, water intake and litter moisture. The DEB 50, 150 and 250 maintained better blood pH, pCO2 and HCO3 concentrations during acute heat stress periods than that of 0 and 350. The blood heterophil and lymphocyte percent as well as heterophil:lymphocyte were remained unaffected. The lowest DEB (0 mEq/kg) diet reduced the feed intake and promoted metabolic acidosis. At 350 mEq/kg DEB, water intake and metabolic alkalosis were promoted probably due to high levels of dietary NaHCO3. The study concluded that overall better performance was recorded with DEB 50, 150 and 250 mEq/kg. These results indicated that single optimal DEB value could not be recommended to combat heat stress in broilers. 相似文献
142.
Timbermont L Lanckriet A Gholamiandehkordi AR Pasmans F Martel A Haesebrouck F Ducatelle R Van Immerseel F 《Comparative immunology, microbiology and infectious diseases》2009,32(6):503-512
Since the ban on growth-promoting antibiotics in animal feed in the European Union, necrotic enteritis has become a major cause of mortality in broiler chickens. Despite the importance of the disease, the pathogenesis is still not completely understood. In the current study, Clostridium perfringens strains isolated from healthy flocks and isolates from outbreaks of necrotic enteritis were evaluated for the ability to cause gut necrosis in an intestinal loop model in laying hens and in an experimental infection model in broilers. High, intermediate and low alpha toxin producing strains were chosen from each isolation source. Only the isolates from field outbreaks induced necrotic gut lesions, independent of the amount of alpha toxin produced in vitro. It was also shown that alpha toxin producing isolates from calf hemorrhagic enteritis cases were not able to induce necrotic enteritis in poultry. These results suggest the presence of host specific virulence factors in C. perfringens strains, isolated from chickens with intestinal necrotic enteritis lesions. 相似文献
143.
Chusnul ARIF Budi Indra SETIAWAN Hanhan Ahmad SOFIYUDDIN Lolly Martina MARTIEF Masaru MIZOGUCHI Ryoichi DOI 《水稻科学》2012,19(2):143-152
The current study proposes a novel method using Excel Solver to estimate,from limited data,crop coefficient(Kc) in paddy fields under intermittent irrigation(II).The proposed method was examined in a field experiment conducted at Karang Sari Village,Bekasi,West Java,Indonesia during the first rice season of 2007/2008(December 2007 to April 2008) in the rainy season.As the control,continuous flooding irrigation(CF) was applied to the conventional rice cultivation fields.Based on the observed water storage,Excel Solver was used to estimate crop evapotranspiration.Estimated crop evapotranspiration was used to compute Kc value,then the average Kc values at each growth stage were compared with that for the CF treatment.The estimation method was evaluated by comparing estimated crop evapotranspiration and the crop evapotranspiration derived by the well established FAO procedure.Excel Solver estimated crop evapotranspiration accurately with R2 values higher than 0.81.Accordingly,more than 81% of the FAO crop evapotranspiration was described by the proposed method.Thus,Kc value could be well determined from those estimated crop evapotranspiration.Under the II treatment,the average Kc values were 0.70,1.06,1.24 and 1.22 for the initial,crop development,reproductive and late stages,respectively.These values were lower than those under the CF treatment for initial and crop development stages because of a minimal soil evaporation and intense dryness during these stages.However,average Kc values under the II treatment were higher than those under the CF treatment at the reproductive and late stages,indicating that the II treatment promoted more plant activity particularly for dry biomass production as indicated by a greater number of tillers per hill. 相似文献
144.
Cellulose fibres and cellulose nanocrystals were extracted from rice husk. Fibres were obtained by submitting the industrial rice crop to alkali (NaOH) and bleaching treatments. Nanocrystals were extracted from these fibres using sulphuric acid (H2SO4) hydrolysis treatment. The material obtained after each stage of the treatments was carefully characterized and its chemical composition was determined. Morphological investigation was performed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Fourier transform infrared (FTIR) spectroscopy showed the progressive removal of non-cellulosic constituents. X-ray diffraction (XRD) analysis revealed that the crystallinity increased with successive treatments. The thermal stability of the rice husk fibres and cellulose nanocrystals was also investigated using thermogravimetric analysis (TGA). 相似文献
145.
Mohammad H. Ahmad Amani M. D. El Mesallamy Fatma Samir Faten Zahran 《Journal Of Applied Aquaculture》2013,25(4):289-298
Four isonitrogenous (30% crude protein) and isocaloric (4.40 kcal/g) experimental diets were formulated to contain 0.0% (control), 0.5%, 1.0%, or 1.5% cinnamon. The diet containing 1% cinnamon resulted in significantly greater (P < 0.05) specific growth rate (SGR), feed conversion ratio (FCR), feed efficiency ratio (FER), protein efficiency ratio (PER), apparent protein utilization (APU), and energy utilization (EU). In regard to body composition, there was no significant difference in dry matter, protein, lipids, and ash (P > 0.05) contents due to cinnamon supplementation. Blood plasma profile showed an improvement in hemoglobin (HB), red blood cell (RBCS), hematocrite (PCV), total protein, and total lipids, while there was a decrease in creatinin, urea, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glucose in fish fed 1% cinnamon. Cinnamon was found to have an antibacterial activity antagonistic to Aeromonas hydrophila infection in fish. Performance and FCR improvement translated into a 10% decrease in feed costs associated with the 1% cinnamon diet. 相似文献
146.
Zabihallah Bahmani Masoud Rezaei Seyed Vali Hosseini Seyed Fakhreddin Hosseini Alireza Alishahi Mehraj Ahmad 《Journal Of Aquatic Food Product Technology》2013,22(6):542-551
Research has shown that fresh fish is an extremely perishable food as compared to other food commodities. In this study, quality deterioration during storage of golden grey mullet (GGM) iced for 0, 6, and 12 h after landing was monitored. Microbiological indices (total viable count, TVC; psychrophilic counts, PTC; lactic acid bacteria, LAB; and Enterobacteriaceae counts, EBC), chemical parameters (pH; total volatile basic nitrogen, TVB-N; peroxide value, PV; thiobarbituric acid, TBA; and free fatty acids, FFA) values increased over the preicing duration. Delayed icing did not lead to significant increases (p > 0.05) in TVC, PTC, LAB, and EBC throughout the period of storage. All chemical indices increased during storage (p < 0.05). This study showed that sensorial analysis of GGM correlated well with microbiological analysis. Results of this study based on the microbiological and raw fish sensorial data indicated that the shelf life of GGM stored in ice immediately after catch was approximately 10–11 days, while the 6- and 12-h delays in icing shortened the shelf life to approximately 6–7 and 2–3 days, respectively. 相似文献
147.
Farag Sallabi Moustafa FadelAhmed Hussein Ahmad JaffarHazem El Khatib 《Computers and Electronics in Agriculture》2011,76(1):28-37
Documentation is a major component of any traceability system where traceability is defined in the ISO Regulation 8402:1994 as the ability to trace the history, application and location of what is under consideration. Traceability systems are record keeping systems designed to track the flow of product or product attributes through the production process or supply chain. All international supply chains are forced to comply with traceability requirements. In this paper, we develop and implement an end-to-end mobile application prototype that traces the poultry production. This application consists of front-end and back-end systems. At the front-end, the worker uses a GPRS enabled handheld device (cell phone, PDA, etc.) to capture information on poultry operations collected at a remote chicken farm and transmit it to a back-end server in the main office. Through customized application the back-end server analyses all information received from the front-end and based on a built-in business process and business rules, intelligently updates various stakeholders of any breach of bio-security measures that requires immediate attention. The proposed system administrators can also access this application via Internet for management decision making. The back-end system consists of web server, defined business application logic and database server. 相似文献
148.
Shahid Iqbal Awan Muhammad Shahzad Ahmed Jehanzeb Farooq Syed Dilnawaz Ahmad Muhammad Ilyas Asad Hussain Shah Muhammad Fareed Khan Sardar Ali Lutful Hasan 《Frontiers of Agriculture in China》2011,5(4):486-496
An experiment was conducted to access the genetic variability among early vigour and quantitative traits under limited moisture
in F2 generation of a 5 × 5 diallel cross of bread wheat. The results indicated that there was significant genotypic variation
among the genotypes. Additive dominance model revealed full fitness of the data for RL, DSW, FRW, DRW, spike length, and 1000-grain
weight but was partially fit for SL, FSW, R/S, tillers per seedling, plant height, tillers per plant, spikelets per spike,
and grain yield per plant. The partially adequate models for these plant characters might be due to the presence of non-allelic
interaction, linkage, and non-independent distribution of the genes in the parents. Additive genes coupled with moderate to
high narrow sense heritability were involved in the heritage of all the traits, which indicated a higher scope of selection
in early generations. 相似文献
149.
Gregory F.L. Koay Teong-Guan Chuah Sumaiya Zainal-Abidin Salmiah Ahmad Thomas S.Y. Choong 《Industrial Crops and Products》2011,34(1):1135-1140
Crude dihydroxystearic acid was prepared from palm based oleic acid and was then solvent purified with isopropyl alcohol in a custom fabricated simultaneous batch crystallizer unit. The crystallized dihydroxystearic acid was a functional ingredient that acted as multipurpose intermediate for synthesis of various fine chemicals, cosmetics and personal care products. The effects of solvent quantity and concentration on particle size distribution, crystal habit and morphology, and resultant crystal purity were studied. The crystals were purer but smaller and the span of the distribution curve was wider at higher solvent quantity and concentration. Through scanning electron microscopy and X-ray diffraction, it was observed that the crystals agglomerated into plate-like (flaky) habit with triclinic crystal structure. Solvent crystallization with 80% IPA at 20 °C and solute:solvent ratio of 1.0:1.0 was the most optimized and efficient, producing β-DHSA crystals that has high resistance against fat exudation during vacuum filtration process. 相似文献
150.
Roziana Kamaludin Mohd Hafiz Dzarfan Othman Siti Hamimah Sheikh Abdul Kadir Ahmad Fauzi Ismail Mukhlis A. Rahman Juhana Jaafar 《Water, air, and soil pollution》2018,229(11):363
Bisphenol A (BPA) and reactive black 5 (RB5) dye are among the most persistent and non-biodegradable contaminants in water which require an urgent need for the development of effective removal method. The ubiquitous existence of both contaminants could interfere with the human health and aquatic environmental balance. Photocatalytic process as one of advanced oxidation processes (AOPs) has shown high performance for degradation of organic compounds to the harmless materials under sensible condition. Therefore, this study aims to develop a visible-light-driven photocatalyst that can efficiently degrade BPA and RB5 present in household water. N-doped TiO2 were successfully synthesized via simple and direct sol–gel method. The prepared TiO2 nanoparticles were characterized by field emission scanning microscope (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and Brunauere Emmette Teller (BET) analysis. The incorporation of nitrogen in TiO2 lattice exhibited excellent optical responses to visible region as revealed by UV–Vis–NIR spectroscopy absorption capability at 400–600 nm. The photocatalytic activity of the N-doped TiO2 nanoparticles was measured by photocatalytic degradation of BPA and RB5 in an aqueous solution under visible-light irradiations. Degradation of BPA and RB5 was 91.3% and 89.1%, respectively after 360 min illumination. The degradation of BPA and RB5 by N-doped TiO2 was increased up to 89.8% and 88.4%, respectively under visible-light irradiation as compared to commercial TiO2 P25. This finding clearly shows that N-doped TiO2 exhibits excellent photocatalytic degradation of BPA and RB5 under visible irradiation, hence have a promising potential in removing various recalcitrant contaminants for water treatment to fulfill the public need to consume clean water. 相似文献