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201.
202.
Diurnal and oviposition patterns of heart rate (HR), deep body temperature (BT) and locomotor activity (LA) in conscious and unrestrained Rhode Island Red hens were studied by a radiotelemetry system. Behavioral observations were also made on diurnal changes and during the pre‐ and post‐laying period. Heart rate, BT and LA showed characteristic diurnal changes synchronized with a photoperiod of 15 h light and 9 h dark. In the light period, HR, BT, and LA levels were significantly higher than in the dark period (P < 0.001). Furthermore, the highest levels of these parameters were recorded just after they were fed (08.30 hours), while the lowest level was measured after lights‐off and remained stable throughout the dark period. Behavioral observations indicated that during the light period the hens spent most of their time in very active movement, exhibiting various behavioral patterns. However, in the dark period the hens spent almost all their time resting. The present results suggest that performing various behavioral activities cause heat generated by muscle exertion, which plays a significant role in daily HR, BT, and LA in laying hens. However, during the 60 min before and after oviposition, LA appeared to have increased steadily toward the moment of laying, and then regressed gradually in the post‐laying period to a level significantly lower than in the pre‐laying period (P < 0.001). Furthermore, the pre‐laying behavior of hens indicated extreme restlessness and more activity, whereas the post‐laying period is characterized by less activity and increased relaxation. Consequently, laying behavior has a profound but transitory effect on HR and BT, suggesting that oviposition was probably associated with intense LA. 相似文献
203.
A battery trial was conducted to evaluate the comparative pathogenicity of five field strains of Eimeria tenella from Behera, Khafr El-Sheikh, Alexandria, Gharbia and Matrouh provinces in Egypt. Two-week-old broiler chickens were infected with 25×10(3) sporulated oocysts of each strain of E. tenella. The comparative pathogenicity of the strains was assessed by calculating body weight gain, feed conversion ratio, lesion scores, dropping nature scores, cecal scrapings, mortality percentage and oocysts count. Hematological parameters including hemoglobin (Hb) content, packed cell volume (PCV%) and total erythrocytic count, were also evaluated. There were different degrees of pathogenicity between the strains. 相似文献
204.
Cengiz Kaya Muhammed Ashraf Osman Sonmez Salih Aydemir Atilla Levent Tuna Mehmet Ali Cullu 《Scientia Horticulturae》2009
This study investigated the effects of arbuscular mycorrhizal (AM) colonisation by Glomus clarum on growth and fruit yield of pepper (Capsicum annum cv. 11B 14) grown at high salinity. The experiment was conducted in pots containing a mixture of perlite and sand (1:1, v/v) under glasshouse conditions. Treatments were: (1) no added NaCl without arbuscular mycorrhizae (NS-AM), (2) no added NaCl with arbuscular mycorrhizae (NS + AM), (3) added 50 mM NaCl without arbuscular mycorrhizae (S1-AM) and (4) added 100 mM NaCl without arbuscular mycorrhizae (S2-AM), (5) added 50 mM NaCl with arbuscular mycorrhizae (S1 + AM) and (4) added 100 mM NaCl with arbuscular mycorrhizae (S2 + AM). The NaCl treatments reduced pepper shoot and root dry matter, and fruit yield compared with the non-saline treatments. The concentrations of N, P and K, in the leaves were significantly reduced by salinity stress, however, mycorrhizal colonisation of the salt-stressed plants restored leaf nutrient concentrations to the levels in non-stressed plants in most cases. AM inoculation improved pepper growth under salt or saltless conditions and reduced cell membrane leakage. 相似文献
205.
Ashraf M. A.?Abdalla Noboru?SekinoEmail author Norikai?Jinbo 《Journal of Wood Science》2004,50(3):223-229
I-beams flanged with veneer strands with medium density fiberboard (MDF) or particleboard as web material were produced by hot pressing. The forming and pressing method used a special metallic mould that allowed flanges to be formed and bonded to the web at the same time. Many I-beams were able to be produced in a single hot pressing cycle and this method allows the utilization of residues and wastes from wood and wood-composite industries. The forming and pressing method was found to be technically suitable for the production of such I-beams. The fundamental properties of the specimens produced were assessed and the results indicated that the I-beams had promising mechanical properties; for example, the modulus of rupture ranged from 40 to 56MPa depending on the flange density. The bond quality between the web and flange was found to have a critical effect on the strength of the entire I-beam. The I-beams were found to have relatively high bond strengths between the web and flange, ranging from 3.3 to 5.0MPa in the parallel direction. The dimensional stability of the I-beams was found to be excellent in the thickness direction of the beam, but not in the compression (width) direction.Part of this paper was presented at the 53rd Annual Meeting of the Japan Wood Research Society in Fukuoka, March 2003 相似文献
206.
The balance of strength between the flange and web parts of veneer strand flanged I-beam was investigated by the following
methods: (1) use of different web material types, such as plywood, oriented strand board (OSB), particleboard (PB), and medium
density fiberboard (MDF), that have different strength properties; and (2) fabrication of I-beams with low-density flanges
using low-density strands with PB web material. Replacing PB or MDF with plywood showed slight significant improvement in
the modulus of rupture but not in the modulus of elasticity of the entire I-beam. However, PB and MDF showed competent performance
in comparison with OSB, thus strengthening the promising future of the use of PB or MDF as web material to fabricate I-beams.
Hot-pressing conditions used for I-beam production exerted slightly adverse effects on the bending properties of PB, but not
on MDF, OSB, and plywood web materials. The flange density of 0.60 g/cm3 was considered to be the lower limit that provides I-beams with balanced mechanical properties and dimensional stability. 相似文献
207.
Arshad Naji Alhasnawi Che Radziah Che Mohd Zain Ahsan A. Kadhimi Anizan Isahakb Azhar Mohamad Mehdi Farshad Ashraf Wan Mohtar Wan Yusoff 《Journal of Crop Science and Biotechnology》2016,19(5):353-362
Salt stress is considered to be the most important abiotic stress and is the main problem in the interruption of the metabolic processes of plants, thereby limiting crop production. The present study was carried out to examine the effects of exogenously applied mushroom polysaccharides (β-glucan) on the growth of two rice varieties of Oryza sativa L. (MRQ74 and MR269) seedlings grown in vitro in 200 Mm sodium chloride (NaCl). Growth characteristics, including shoot and root height, and fresh and dry weight of salt-stressed rice seedlings were inhibited by sodium chloride treatment, the degree of which depends on the rice variety. The negative effects of salinity stress resulted in an imbalance of N, K+ Na+ and Na/K ratios and biochemical analysis activities a degradation of chlorophyll content in the plants. However, treatment with exogenously applied polysaccharides (β-glucan) ameliorated the stress generated by NaCl and improved the parameters mentioned above. The significance of the changes in growth and metabolism to salt stress tolerance in rice seedlings are discussed in the paper. 相似文献
208.
Porcine intestinal mucosal mast cells (IMMC) were isolated from intestinal tissues of swine by enzymatic digestion and density gradient separation. Helminth-free swine and swine exposed to the nematode parasite, Ascaris suum, were used as a source of intestinal tissue. Up to 40% of the isolated intestinal cells stained metachromatically with toluidine blue pH 3.0, indicating the presence of IMMC. The histamine content of this cell population ranged from 2.9-8.9 pg per toluidine blue-positive IMMC, regardless of the animal source. Enrichment procedures that increased the proportion of toluidine blue-positive IMMC from the isolated intestinal cell population correlated with an increase in the amount of histamine detected in the cell population, indicating that toluidine blue-positive IMMC were the major source of histamine in this heterogeneous cell population. However, only cells isolated from the intestines of parasite-exposed swine released histamine in vitro after mixing with antigens derived from A. suum. Cells from the intestines of both helminth-free and parasite-exposed swine did not release histamine after mixing with a non-parasite hapten-protein molecule DNP-human serum albumin, but did release greater than 90% of their total histamine after lysis with Triton X-100 or with the Ca2+ ionophore (A23187). The stimulus for acquired responsiveness of IMMC to A. suum antigens in vitro was parasitic infection in vivo because helminth-free swine maintained in confinement on concrete yielded IMMC that specifically released histamine in the presence of parasite antigens only after 3 weeks of daily experimental inoculations with A. suum eggs. IMMC isolated from the entire length of the small intestines of infected pigs were responsive to antigens in vitro, but the relative number of IMMC isolated and their level of histamine release decreased from the anterior to the posterior end. IMMC isolated from infected swine were also stimulated to release histamine in vitro by viable second stage larvae of A. suum and by treatment with anti-swine immunoglobulin. Responsiveness to both parasite antigens and anti-immunoglobulin were totally eliminated, however, by a brief treatment of the cells with acidic buffer, suggesting that an acid-dissociable cell-bound antibody molecule was responsible for specific antigen-induced histamine release by IMMC. 相似文献
209.
Mohammed A. Elmetwally Alaa Samy Ashraf Eldesouky Yasser Y. Lenis Wael Eldomany 《Animal Science Journal》2021,92(1):e13563
This prospective study was designed to investigate the effects of maternal temperament on uterine blood flow, fetal heart rate, gestational length, and fetal birth weight in a goat experimental model. Based on the arena test, behavioral testing related to fear-eliciting stimulus, goats were divided into nervous (n = 13) and calm (n = 11) groups. After mating, the perfusion of maternal uterine arteries (UTAs) and its related Doppler parameters, blood flow volume (BFV), time-averaged mean velocity (TAMEANV), acceleration (Acce), and resistance impedance (S/D), were evaluated biweekly from week two until the end of pregnancy. Fetal heart rate (FHR) was investigated during the pregnancy in addition to the gestation length (GL) and fetal birth weight (FBW). The UTA-BFV and TAMEANV, as well as Acce and S/D, were influenced by maternal temperament (p < .05). The FHR showed no significant changes between experimental animals of different temperaments (p = .81). Both GL and FBW were increased in calm rather than nervous goats (p < .05). These results indicated that the maternal nervous (temperament) have negative impacts on uterine artery Doppler indices, fetal growth, and gestational length in a goat experimental model. 相似文献
210.
Journal of Plant Diseases and Protection - Fusarium oxysporum f. sp. capsici (Foc) induces wilt disease in chilli and affects its yield. Implementing microorganisms and plant extracts for plant... 相似文献