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81.
Mounir Louhaichi Sawsan Hassan Kathryn Clifton Douglas E. Johnson 《Agroforestry Systems》2018,92(5):1341-1352
Despite the importance of fodder shrubs to small ruminant diets and production in arid and semi-arid ecosystems, they are often not considered when quantifying grazing land potential. This oversight is mainly due to the time consuming and costly traditional techniques used to estimate shrub biomass. The shrub fodder component should be measured to avoid underestimation of the carrying capacity of rangelands. In this study, we present a fast, reliable and non-destructive method to estimate canopy vegetation cover to obtain aboveground shrub biomass. The experiment was conducted under field conditions in northwest Syria, where seedlings of seven shrub species were monitored for one year: Atriplex leucoclada (Moq.) Boiss., A. halimus L., A. lentiformis (Torr.) S. Watson, A. canescens (Pursh) Nutt., A. nummularia Lindl., Salsola vermiculata L. and Haloxylon aphyllum (C.A. Meyer) Bunge. The experimental layout was a randomized complete block design with five replications. We explored the effectiveness of digital vegetation charting technique (DVCT) for estimating shrub canopy cover. Aboveground shrub biomass was clipped to estimate the dry matter (DM) weight per species and to determine its relationship to canopy cover. In this study, an estimate of greenness (percent green vegetation cover) was extracted by way of greenness algorithms. Simple linear regressions between vegetation cover and biomass for 210 plots were performed. The cover of the seven species differed (P < 0.01): A. leucoclada had the highest vegetation cover (56%) and H. aphyllum the lowest (7%). Vegetation cover and DM biomass were positively correlated (P < 0.01) with R-squared ranging from 0.66 (H. aphyllum) to 0.84 (S. vermiculata). Our method provided reasonable estimations of canopy coverage which could predict aboveground phytomass. We conclude that DVCT offers a rapid, reliable and consistent measurement of shrub cover and biomass provided that shrubs have open architecture. This study shows the potential of digital cameras and image processing to determine cover/biomass in a non-destructive, timely and cost efficient way. 相似文献
82.
83.
Nawal Al-Hajaj Gregory W. Peterson Carolee Horbach Khaled Al-Shamaa Nicholas A. Tinker Yong-Bi Fu 《Genetic Resources and Crop Evolution》2018,65(8):2069-2082
Recent advances in next generation sequencing technologies make genotyping-by-sequencing (GBS) more feasible for molecular characterization of plant germplasm with complex and unsequenced genomes. Here we applied the GBS technology to assess the genetic diversity of 275 hexaploid oat wild relative (Avena sterilis) plants collected from 24 natural populations in Jordan. Total genomic DNAs were extracted and digested with restriction enzymes PstI and MspI. Three Illumina MiSeq sequencing runs generated 556 paired-end FASTQ files with 127,128,438 raw sequences. Bioinformatics analysis identified an informative matrix of 275 samples × 12,999 SNP markers. Analysis revealed 52.4% of SNP variation residing among 24 populations and eight major genetic clusters of the samples. Most samples were grouped together within their original populations. A significant association of pairwise population genetic distances was found with latitudinal or longitudinal differences. Two natural populations were highly differentiated from the others, and 30 highly distinct A. sterilis samples were identified from seven populations. These findings are useful for understanding genetic variability and conservation of natural A. sterilis populations, and they demonstrate the advances of the GBS application for germplasm characterization of crop wild relatives with complex genomes. 相似文献
84.
Ghada Baraket Olfa Saddoud Khaled Chatti Messaoud Mars Mohamed Marrakchi Mokhtar Trifi Amel Salhi-Hannachi 《Scientia Horticulturae》2009
Sequences of the internal transcribed spacers (ITSs) of nuclear ribosomal DNA (nrDNA) were analysed in a set of Tunisian fig (Ficus carica L.) cultivars. The size of the spacers sequences ranged from 200 to 279 bases for ITS1 and from 253 to 314 bases for ITS2. Variation of GC contents has been also observed and scored as 59–68% and 55–68% for ITS1 and ITS2, respectively. This data exhibited the presence of polymorphism among cultivars. The intra-specific variability level of the ITS sequences proved a variation both in the length and in the sequences studied. In fact, ITS1 and ITS2 sequences were considered as a useful tool to establish genetic relationships among cultivars. Our results indicate that the diversity detected among closely related genotypes supported strongly the efficiency of ITS sequences for establishing relationships between cultivars. ITS2 seems to be relatively more informative than ITS1 regarding length or GC contents. Considerable genetic diversity was observed among fig at intra and inter-cultivars levels. Two polyclonal varieties were identified. In addition, data proved that a typically continuous genetic diversity characterizes the local fig germplasm. The topology of the derived dendrogram strongly supported this assumption. In fact, genotypes are clustered independently from their geographical origin or the sex of trees suggesting a narrow genetic basis among the ecotypes studied in spite of their phenotypic distinctiveness. Implications of these results for management of fig germplasm collections are discussed. 相似文献
85.
Mohammed H. Belal Hosni S. M. Fahmy Mounir D. Abdallah Toson M. Awad 《Pest management science》1978,9(1):63-64
A study of phosfolan deposited from sprays indicated that most of it is degraded within a week in the presence of light and air. It disappears more rapidly on cotton leaves than on glass because much of it migrates into the leaf interior within 7 h of application. Degradation within the leaf proceeds more slowly than on the leaf surface or on glass. 相似文献
86.
Sameh S. Elhady Eman S. Habib Reda F. A. Abdelhameed Marwa S. Goda Reem M. Hazem Eman T. Mehanna Mohamed A. Helal Khaled M. Hosny Reem M. Diri Hashim A. Hassanean Amany K. Ibrahim Enas E. Eltamany Usama Ramadan Abdelmohsen Safwat A. Ahmed 《Marine drugs》2022,20(1)
Different classes of phytochemicals were previously isolated from the Red Sea algae Hypnea musciformis as sterols, ketosteroids, fatty acids, and terpenoids. Herein, we report the isolation of three fatty acids—docosanoic acid 4, hexadecenoic acid 5, and alpha hydroxy octadecanoic acid 6—as well as three ceramides—A (1), B (2), and C (3)—with 9-methyl-sphinga-4,8-dienes and phytosphingosine bases. Additionally, different phytochemicals were determined using the liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry (LC-ESI-HRMS) technique. Ceramides A (1) and B (2) exhibited promising in vitro cytotoxic activity against the human breast adenocarcinoma (MCF-7) cell line when compared with doxorubicin as a positive control. Further in vivo study and biochemical estimation in a mouse model of Ehrlich ascites carcinoma (EAC) revealed that both ceramides A (1) and B (2) at doses of 1 and 2 mg/kg, respectively, significantly decreased the tumor size in mice inoculated with EAC cells. The higher dose (2 mg/kg) of ceramide B (2) particularly expressed the most pronounced decrease in serum levels of vascular endothelial growth factor -B (VEGF-B) and tumor necrosis factor-α (TNF-α) markers, as well as the expression levels of the growth factor midkine in tumor tissue relative to the EAC control group. The highest expression of apoptotic factors, p53, Bax, and caspase 3 was observed in the same group that received 2 mg/kg of ceramide B (2). Molecular docking simulations suggested that ceramides A (1) and B (2) could bind in the deep grove between the H2 helix and the Ser240-P250 loop of p53, preventing its interaction with MDM2 and leading to its accumulation. In conclusion, this study reports the cytotoxic, apoptotic, and antiangiogenic effects of ceramides isolated from the Red Sea algae Hypnea musciformis in an experimental model of EAC. 相似文献
87.
Mounir Adnane Kieran G. Meade Cliona O’Farrelly 《Veterinary research communications》2018,42(4):255-263
Cervico-vaginal mucus (CVM), the product of epithelial cells lining the uterus, cervix and vagina, is secreted to facilitate uterine lubrication and microbial clearance. Predominantly composed of water and mucins, CVM also contains high levels of immuno-active proteins such as immunoglobulin A (IgA), lactoferrin and lysozyme which protect against infection by blocking adhesion and mediating microbial killing. The repertoire of cytokines, chemokines and antimicrobial peptides is predominantly generated by the secretions of endometrial epithelial cells into the uterine lumen and concentrated in the CVM. The quantity and relative proportions of these inflammatory biomarkers are affected by diverse factors including the estrus cycle and health status of the animal and therefore potentially provide important diagnostic and prognostic indicators. We propose that measuring molecular signatures in bovine CVM could be a useful approach to identifying and monitoring genital tract pathologies in beef and dairy cows. 相似文献
88.
Khaled Abo-EL-Sooud Gamal A. Swielim Samar M. EL-Gammal Meray Nabil Ramsis 《Journal of veterinary pharmacology and therapeutics》2020,43(4):313-318
The pharmacokinetics of marbofloxacin (MAR) was compared in geese (Anser Anser domesticus) after single intravenous (IV) and intramuscular (IM) (thigh and pectoral muscles) administrations of 5 mg/kg. Serum concentrations of MAR were determined with high-performance liquid chromatography (HPLC) method. Serum MAR concentrations versus time were analyzed by a noncompartmental method. After IV administration, MAR showed high volume of distribution at steady state (Vdss) of 5.24 ± 1.08 L/kg. The serum body clearance (Cl) and elimination half-life (T1/2λz) of MAR were 0.79 ± 0.07 L hr−1 kg−1 and 6.94 ± 1.12 hr, respectively. The peak of MAR serum concentrations Cmax achieved at one and 0.50 hr after thigh and pectoral IM sites of injections, respectively, were 1.20 and 0.91 μg/ml. Significant differences were found in the mean absorption time (MAT), the systemic bioavailability (F%), and elimination parameters of MAR between two sites of injections, indicating that the absorption was fairly slow and complete after thigh IM injection. The pharmacokinetics of MAR in geese diverged according to the site of IM injection following a parallel study design. We recommend the thigh muscle as IM site of injection to obtain maximum concentrations of the administered drug in geese. 相似文献
89.
The objectives were to evaluate the reproductive indices and survival analysis of pregnancy outcomes in multiparous repeat breeder Holstein cows (n = 557). The cows were synchronized to ovulate by Ovsynch, new controlled internal drug release device (N‐CIDRsynch), and once‐used CIDR device (U‐CIDRsynch). The pregnancy per AI at 28 days post‐insemination (P/AI 28) in the N‐CIDRsynch group (28.75%) was significantly (COR = 1.49; p = 0.011) greater than that reported in the Ovsynch (23.46%) and U‐CIDRsynch (21.73%) groups. Furthermore, the pregnancy per AI at day 75 post‐insemination (P/AI 75) in the N‐CIDRsynch group was significantly greater than the Ovysync group (COR = 1.35; p = 0.050). The repeat breeder cows received a N‐CIDR device had a significantly higher progesterone level on day 2 and day 4 of CIDR insertion (1.38 and 1.67 ng/ml, respectively) than those received a U‐CIDR device or the control group (p = 0.012 and 0.001, respectively). The Cox regression model recorded significant associations for synchronization protocols, THI at the TAI and season of calving with the hazard of P/AI 28 and P/AI 75 (p = 0.044 and 0.046; 0.001 and 0.005; 0.003 and 0.001, respectively). Multiparous repeat breeder cows (>3) had a lower hazard ratio (HR) of P/AI 28 than that reported in the reference (2nd parity) group (HR = 0.74, p = 0.050). The repeat breeder cows inseminated at 76–80 and >80 temperature‐humidity index (THI) had significantly lower HR of P/AI 28 than those inseminated at the baseline (<70) THI value (HR = 0.73 and 0.30, p = 0.036 and 0.001, respectively). The current results indicate that the use of N‐CIDR synch protocol may achieve satisfactory pregnancy outcomes in repeat breeder cows. 相似文献
90.
El-Dakhly KM El-Nesr KA El-Nahass el-S Hirata A Sakai H Yanai T 《Tropical animal health and production》2011,43(8):1549-1554
This study was performed for the purpose of investigating the prevalence of Sarcocystis spp. in buffaloes in Beni-Suef Governorate, Egypt. Both macroscopic (Sarcocystis fusiformis) and microscopic (Sarcocystis levinei) cysts were recognized, and were differentiated by their morphological features and location in the tissues. Of 379 buffaloes
examined in abattoirs in Beni-Suef, 299 were found to be infected, with an overall prevalence of 78.9%. Depending on age,
three categorized groups of naturally infected buffaloes were examined: male buffalo calves aged 1.5–2 years, adult females
aged 2–5 years, and females older than 5 years. Among these groups, infection rates were 74.5%, 82.3%, and 81.2%, respectively.
Organs examined included esophagus, tongue, and heart. Macroscopic cysts were examined by the naked eye through meat inspection
in abattoirs, while the pepsin-digestion method and the histological technique were applied to detect microscopic cysts. It
has been found that esophagus showed the highest rate of infection among the infected organs, with both macroscopic and microscopic
cysts seen in the infected buffaloes. Moreover, results of the pepsin-digestion method proved more accurate than those produced
by the histological technique in terms of infection rates for the microscopic cysts. Our findings indicated that infected
buffaloes aged 2–5 years showed the highest mixed infection rate (82.3%) for both types of cysts. The high prevalence of microscopic
Sarcocystis spp. in Beni-Suef Governorate reflects a significant role played by stray dogs, rather than cats, in the transmission of
these parasites. 相似文献