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11.
Our objective was to evaluate life-cycle performance of flocks of two Egyptian breeds, Rahmani (R) and Ossimi (O), and their crosses with Finnish Landrace (F) in two management systems. Management systems were one mating season per year (1M) and three mating seasons per 2 yr (3M). Breeds and crosses studied included purebred R and O, F1 crosses 1/2F-1/2R (FR) and 1/2F-1/2O (FO), and inter se matings of 1/4 F-3/4 R (RFR) and 1/4 F-3/4 O (OFO). A dynamic computer model was used to simulate animal performance and enterprise efficiency and profit. Two measures of lifecycle feed conversion (biological efficiency) were computed: kilograms of TDN input per kilograms of empty body weight output (TDN/EBW) and kilograms of TDN input per kilogram of carcass lean output (TDN/CLN). Profit was measured as gross margin (income minus variable costs per ewe per year, GM/EWE). Input parameters for the model were obtained from published results and analyses of data collected from experimental flocks of the same genetic stocks in Egypt. Profit for FR and RFR was 42 and 6% higher in 1M than in 3M. However, profit for all other genetic types was 4 to 8% greater in 3M than in 1M. Breed rankings changed depending on the measure of evaluation (i.e., biological efficiency or profit). Maximization of system output did not necessarily improve efficiency. Under accelerated lambing systems, greater overhead costs associated with labor and feed offset gains in ewe productivity. Genetic stocks should be matched to resources and management systems. 相似文献
12.
Desneux Nicolas Han Peng Mansour Ramzi Arn Judit Brvault Thierry Campos Mateus R. Chailleux Anais Guedes Raul N. C. Karimi Javad Konan Kouassi Arthur J. Lavoir Anne-violette Luna Mara G. Perez-Hedo Meritxell Urbaneja Alberto Verheggen Franois J. Zappal Lucia Abbes Khaled Ali Abid Bayram Yunus Cantor Fernando Cuthbertson Andrew G. S. De Vis Raf Erler Fedai Firake Dnyaneshwar M. Haddi Khalid Hajjar M. Jamal Ismoilov Khasan Jaworski Coline C. Kenis Marc Liu Hao-tian Madadi Hossein Martin Thibaud Mazih Ahmed J. Messelink Gerben Mohamed Samira A. Nofemela Robert S. Oke Abiola Ramos Csar Ricupero Michele Roditakis Emmanouil Shashank Pathour R. Wan Fang-Hao Wang Ming-hui Wang Su Zhang Yi-Bo Biondi Antonio 《Journal of pest science》2022,95(1):17-39
Journal of Pest Science - The South American tomato pinworm, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), has invaded most Afro-Eurasian countries and is threatening worldwide tomato... 相似文献
13.
Abbaszadeh Akbar Mozanzadeh Mansour Torfi Qasemi Ahmad Oujifard Amin Nafisi Bahabadi Mahmod 《Aquaculture International》2022,30(2):653-676
Aquaculture International - A 56-day study was carried out to examine the addition of live foods a biofloc technology (BFT) system on Penaeus vannamei postlarvae performance (PL25, initial weight:... 相似文献
14.
Genetic Resources and Crop Evolution - Sumac (Rhus coriaria L.) has been used in human nutrition as an herbal drug to treat different diseases for centuries. In recent years, the genetic... 相似文献
15.
Microspore populations of eight Fhybrids of winter wheat (Triticum aestivum L.) whose parents had different levels of resistance to Fusarium were screened in vitro, using phytotoxins of Fusarium as biochemical probe. Two selection methods were compared for the in vitro selection: either embryoids and calli were first initiated from anthers in toxin-free medium and then grown on medium with 0.3—0.9 %Fusarium toxin; or anthers were immediately cultured in modified liquid potato-2 medium in the presence of 1.5, 2.0 and 2.5ml Fusarium toxin per liter culture medium, a concentration which reduced the number of calli and embryoids to about 10 % compared to the toxin-free controls. Microspores from donor hybrids which were produced from very susceptible cultivars were killed by lower toxin concentrations than micro-spores from hybrids of less susceptible parents. From surviving calli and embryoids, originally initiated from 242,000 anthers in both procedures a total of 375 green lines could be regenerated. The results indicate that it is possible to enrich the fraction of regenerating microspores by those which contain the gene complex responsible for reduced susceptibility to Fusarium by the use of a pathotoxin. 相似文献
16.
Amantadine: neuromuscular blockade by suppression of ionic conductance of the acetylcholine receptor 总被引:5,自引:0,他引:5
E X Albuquerque A T Eldefrawi M E Eldefrawi N A Mansour M C Tsai 《Science (New York, N.Y.)》1978,199(4330):788-790
Amantadine hydrochloride decreases the sensitivity of denervated mammalian muscle to iontophoretically applied acetylcholine. The drug depresses the amplitude of the end-plate current and reverses the slope of the relation between half-decay time and membrane potential suggesting that it alters the ionic conductance that is mediated by the acetylcholine receptor. Binding studies confirm that amantadine acts on the ion conductance modulator rather than the acetylcholine receptor. 相似文献
17.
B.M.M. Mansour 《Scientia Horticulturae》1975,3(2):129-135
Hibiscus sabdariffa L. was found to show an ambiphotoperiodic reaction, flowering both in short days and in extremely long days, but remaining vegetative (at least at 21–25° C) in a 16 h day. Flowering had a dual effect on growth. When floral induction was strong, lateral buds developed into flowers and the number of branches was proportionally reduced. The first stage of floral induction, however, was accompanied by a decrease of apical dominance. Plants shifted to long days after only a short stay at an inductive daylength, and plants moved to short days after a prolonged stay in long days, formed many more branches and a much greater vegetative mass than plants grown in continuous short days or long days.Plants were already sensitive to daylength in the cotyledon stage. Floral induction was not carried over from short days into long days. After marginal induction, floral buds reverted to vegetative shoots, or aborted and were replaced by a shoot from the axil of a bract.In short days, seedlings form shallowly three-lobed leaves until the generative stage, when only entire leaves are formed. In long days, the leaves are deeply five-lobed, also when the plant flowers. 相似文献
18.
Employing a purified lgG fraction of a polyclonal anti-AT1 receptor anti-body, raised against a synthetic octapeptide encompassing residues 14-21 of the first extracellular domain of the AT1 polypeptide, selective AT1 receptor expression was immunohistochemically demonstrable within renal structures in Sprague-Dawley (SD) rats and the desert rodent Meriones crassus. In both animal models, prominent AT1 receptor labelling was evident in renal vascular elements, particularly cortical inter-lobular arteries (IA) as well as vasa recta bundles in the inner stripe of the outer medulla. Less intense labelling was observed among peritubular capillary endothelia within the deep cortex, and at both the outer stripe and the inter-bundle regions of the inner stripe of the outer medulla. The binding of the anti-peptide anti-body was, however, lacking among glomeruli and, except for the intense labelling confined to basement membranes of Bowman's capsule of deep nephrons, was virtually absent in all renal tubular structures of both animal models. Structural assessment of the expressed AT1 receptors by two-dimensional Western blotting revealed that a spectrum of structurally distinct AT1 receptor isoforms is expressed in the renal tissues of both animal models. This spectrum was constituted by isoforms of equal size (70 kDa) but distinct pls in SD rats, and of both different sizes (67-73 kDa) and isoelectric points in M. crassus. In either species, the charge and/or size heterogeneity of AT1 receptor isoforms may be attributed in part to differential post-translational glycosylation mechanisms of the AT1 receptor polypeptide backbone. The potential for the differential glycosylation state of AT1 receptors to alter recognition properties may add another level of complexity to tissue-specific and/or species-specific mechanisms underlying angiotensin II interactions in the kidney. 相似文献
19.
Kim Jye Lee-Chang Matthew C. Taylor Guy Drummond Roger J. Mulder Maged Peter Mansour Mina Brock Peter D. Nichols 《Marine drugs》2021,19(7)
The Labyrinthulomycetes or Labyrinthulea are a class of protists that produce a network of filaments that enable the cells to glide along and absorb nutrients. One of the main two Labyrinthulea groups is the thraustochytrids, which are becoming an increasingly recognised and commercially used alternate source of long-chain (LC, ≥C20) omega-3 containing oils. This study demonstrates, to our knowledge for the first time, the regiospecificity of the triacylglycerol (TAG) fraction derived from Australian thraustochytrid Aurantiochytrium sp. strain TC 20 obtained using 13C nuclear magnetic resonance spectroscopy (13C NMR) analysis. The DHA present in the TC 20 TAG fraction was determined to be concentrated in the sn-2 position, with TAG (16:0/22:6/16:0) identified as the main species present. The sn-2 preference is similar to that found in salmon and tuna oil, and differs to seal oil containing largely sn-1,3 LC-PUFA. A higher concentration of sn-2 DHA occurred in the thraustochytrid TC 20 oil compared to that of tuna oil. 相似文献
20.
Mohammad Khajeh Mehrizi Sayed Majid Mortazavi Shadpour Mallakpour Seyed Mansour Bidoki Michel Vik Martina Vikova 《Fibers and Polymers》2013,14(10):1620-1626
In this study, cotton/nylon blended fabrics were treated with atmospheric air plasma at various times (30–60 s) and were subsequently printed with pastes containing carbon black nanoparticles. Properties of plasma treated fabrics such as visible-near infrared (Vis-NIR) reflectance, water contact angle, air permeability, and color fastness were measured. It was shown that increasing plasma treatment time decreases reflection level of treated fabrics in Vis-NIR region. Plasma treatment also enhanced the hydrophobicity of cotton/nylon fabrics observed by an increase in water contact angle. Plasma treated samples for 60 s demonstrated lower air permeability than those treated for 30 s. Furthermore, printed samples possessed acceptable levels of fastness against washing, light and crocking. 相似文献