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1.
Tropical Animal Health and Production - Newcastle disease (ND) is a devastating disease and cause high t mortality and morbidity in poultry and nonpoultry avian species worldwide. An intensive...  相似文献   
2.
To investigate the nutritional value of the marine micro‐alga Isochrysis galbana Tahitian Isochrysis strain (T.iso) as an alternative feed for aquaculture during culture age, its biochemical composition was studied under autotrophic and controlled culture conditions at different growth stages: exponential phase, early and late stationary phases and decay phase. Analysis showed that C14:0, C16:0, C16:1, C18:4 (n‐3) and C22:6 (n‐3) were the most abundant fatty acids in this alga at different growth stages. The highest values of monounsaturated fatty acids were recorded at the late stationary and the decay phases. However, the highest levels of polyunsaturated fatty acids were observed at the early stationary phase. At all growth stages, I. galbana (T.iso) contained arabinose, xylose, mannose, galactose and glucose. Glucose represented the main sugar, and its content per dry alga biomass weight increased with increasing age of the culture and reached about fourfold in the decay phase. The maximum protein content was also observed during this last phase.  相似文献   
3.
The study here was conducted on nearly 12,000 apricot seedlings in the Malatya Region in the Eastern part of Turkey. This region is famous for its horticulture based mainly on apricot production and the Country's highest apricot production originates from this region. The flower and fruit characteristics of all populations, which include apricot seedlings, in the region were evaluated. Based on their horticultural performances, 13 genotypes were selected, of which seven were considered as apricots served in dried form and six as in table consumption form. Among the selected genotypes, the fruit weight ranged between 28.5 and 71.19 g, soluble solids ranged between 12.7 and 26.5%, while the range in total acidity was between 0.35 and 1.80% and fruit development period was between 87 and 183 days. To determine the selected genotypes performance in a similar environment, they were grafted on to 4-year-old rootstocks. The results from these combinations showed that there was some decrease, especially in fruit size and soluble solids, in the genotypes performance when compared to the results of the initial observations. Some differences were also detected in taste, fruit shape, pit shape, fruit flesh firmness, skin and flesh colors. The dry fruit yield was determined as 22.50–28.36% for the selected dry apricot genotypes. The dry fruit yield of all seven genotypes considered for dry consumption were similar to ‘Hacıhaliloğlu’ and higher than ‘Canino’, which were evaluated as control cultivars.  相似文献   
4.
Two new oleanene saponins were isolated from the MeOH extract of the shell of Argania spinosa.They possess protobassic acid and 16alpha-protobassic acid as aglycons. The disaccharide moiety linked to C-3 of the aglycon is made up of two glucose units; the pentasaccharide moiety linked to C-28 is made up of arabinose, xylose, and three rhamnose units. Their structures were elucidated by 1D and 2D NMR experiments including (1)H-(1)H (DQF-COSY, 1D TOCSY, and 2D HOHAHA) and (1)H-(13)C (HSQC and HMBC) spectroscopy along with mass spectrometry.  相似文献   
5.
Monitoring and assessment of agricultural land degradation is of vital importance for better land and water management planning and reclamation. It requires setting baseline information and basic analysis at specific time and space. About 33 geo-referenced soil sampling spots were selected in two agricultural production locations in the Kingdom of Bahrain to assess the status and preliminary causes of land degradation. Soil samples were taken from 13 sites in Diraz location while 19 samples were taken from Budayyi location. The samples were taken to 90 cm depth at 30 cm intervals. Standard procedures were followed to determine soil physiochemical properties. In addition, field observations on farm condition, distance from the sea, method of irrigation and irrigation water source were taken. Some of the soil samples were deliberately taken from outside the irrigated basins among trees compared with samples taken from inside the actively growing area for comparison. The results indicated that the salinity level was significantly (P 〈 0.001) higher at the 0-30 cm soil depth compared with 30-60 cm or 60-90 cm depths in both locations. The distance from the sea did not show clear correlation with surface soil salinity in Budayyi area compared with Diraz. Both locations showed significantly higher salinity levels on samples taken outside the actively growing areas compared with those taken from within. The effect is more prominent at the 0-30 cm depth. The observed variability on salinity levels may be attributed to farm management practices and deteriorating quality of ground water. Thus, agricultural land degradation in Bahrain cannot be attributed to ground water deterioration alone. The use of tertiary treated sewage water (TSE) may ease the pressure on ground water, but the pH of the TSE should be carefully monitored and managed with proper studies on leaching requirements to avoid further salinity complications.  相似文献   
6.
Genetic Resources and Crop Evolution - Cicer arietinum L. (chickpea) is one of the most significant legume crops domesticated in the Fertile Crescent. This study was aimed to characterize a diverse...  相似文献   
7.
Buffalo is considered short-day breeder in tropical and subtropical part of the world and seasonality and photoperiodism impart major influence on its fertility. However, its impact on in vitro embryo production (IVEP) remains elusive. Therefore, this study investigated the effect of seasonal variations and photoperiodism on morphological and molecular parameters of IVEP in buffalo. For this purpose, we conducted two different experiments on the oocytes obtained by aspirating follicles from abattoir derived ovaries. In Exp. I, retrospective analysis was performed for oocyte recovery, blastocyst and hatching rate, during four consecutive seasonal periods (i.e. January–March, April–June, July–September and October–December). In Exp. II, oocytes from peak breeding and non-breeding seasons were subjected to 24 hr in vitro maturation and evaluated for polar body extrusion to assess maturation rate. Results showed that embryo development was markedly low during second quarter (April–June) and maximum during fourth quarter (October–December) of the year; referred as non-breeding and breeding seasons, respectively. Comparative data analysis demonstrated that poor oocyte quality is major reason for lesser efficiency of embryo production during non-breeding season than peak breeding season as suggested by poor oocyte recovery (2.31 ± 0.10 vs. 3.65 ± 0.27) and maturation rate (33.32 ± 2.1 vs. 63.15 ± 7.31). Subsequently, comparative gene expression analysis of blastocysts during peak breeding season significantly upregulated pluripotency gene (OCT-4) and downregulated heat shock protein 90, as compared to non-breeding season. Therefore, it could be divulged from the present study that seasonal variations and photoperiodism have profound effect on oocyte quality and subsequent embryo development. It is recommended to find suitable additives for in vitro maturation that could mitigate seasonal effects.  相似文献   
8.
In this paper, we report on morphological diversity, ecology and flowering phenological records of an endangered and an endemic species of Morocco Pyrus mamorensis Trab. For this study, a survey was undertaken in North-Western Morocco (Mamora forest and Zaër region) whereby 67 accessions of P. mamorensis were sampled. A set of 33 genotypes of Pyrus spp. from the international collection INRA-Angers (France) of the genus Pyrus were also analyzed. The variability of the total of 100 accessions was assessed by twenty-six characters including fourteen qualitative and twelve quantitative traits. The results demonstrated high levels of morphological variation in the sampled accessions of P. mamorensis and established the relationships among the local germplasm using the UPGMA cluster analysis and the factorial discriminant analysis. Furthermore, we were able to distinguish three types of flowering in the Mamora forest: early, intermediate and late flowering type. Otherwise, the UPGMA classification comparing local accessions of P. mamorensis to the international collection led to the formation of four major groups showing the closest correspondence to their geographical origins: (1) The North African species represented by P. mamorensis, (2) The East Asian pea species, (3) The West Asian species and (4) The European species. These findings suggest the importance of implementing a conservation strategy preserving the genetic resources of wild pear in North-Western Morocco.  相似文献   
9.
This study was carried out to assess the effects of a blend of herbal essential oils (namely Thymus vulgaris, Mentha piperita, Rosmarinus offisinalis and Anethum graveolens) and different dietary lipid sources on the performance, ileal bacterial enumeration, intestinal histological alterations and immune responses in laying hens. For this purpose, a total of 150 laying hens were randomly allocated to six experimental treatments with five replicates of five birds each. Dietary treatments consisted of three levels of a mixture of essential oils (0, 100 and 200 mg/kg) and two sources of lipid (soybean oil and fish oil containing different ratios of n‐6 to n‐3 fatty acids) fed to the animals during an 80‐days feeding trial. Findings indicated that dietary administration of fish oil not only increased significantly the spleen relative weight (p < 0.01) and the antibody titre against Newcastle virus (p < 0.05) but also led to reductions in liver relative weight (p < 0.05) and feed conversion ratio (p < 0.05). Moreover, the mixture of herbal essential oils brought about declines in hepatic relative weight, heterophile to lymphocyte ratio (p < 0.05) and intestinal pathogen populations (p < 0.01). Mention must also be made of the improvements it made in spleen weight (p < 0.01), antibody titres against SRBC (p < 0.01) and Newcastle virus (p < 0.05), villus height to crypt depth ratio (p < 0.01), goblet cell numbers (p < 0.05), lamina propria lymphatic follicle diameters (p < 0.01) and feed conversion ratio (p = 0.06). It may be claimed that the enhancements observed in the performance of laying hens fed fish oil and 200 mg/kg of the blend of essential oils could have potentially been associated with improved intestinal health indices as well as cellular and humoral immune responses.  相似文献   
10.
Poultry litter (PL) is a significant source of nutrients, but a suitable amount of carbon needs to be added as a bulking agent during its composting to a stable nutrient source. Here, we characterized the transformation of phosphorus and other plant nutrients during aerobic composting of PL with sugarcane (SW) and cabbage waste (CW) for 120 d. Periodic samples were collected during composting and analyzed for total C, P (and its fractions), K, Ca, Mg, Cu, Fe, Zn, Mn, EC and pH. At the initial stage of composting (20 d), the P fractions varied in the order: water soluble P > NaHCO3-P (readily plant-available) > HCl-P (Ca+Mg-bound) > residual-P > NaOH-P (Fe+Al-bound). After 120 d, the order was HCl-P > residual-P > water-P > NaHCO3-P > NaOH-P. These variations suggested a transformation of labile Pi to more recalcitrant forms during composting. Water soluble P was the dominant fraction during the initial composting period. This declined progressively with time of composting, while the HCl-P increased, confirming the transformation of the more vulnerable water soluble P to the more recalcitrant HCl-extractable P. This indicated that the composting could be a useful way of managing manure for P stabilization and reducing its losses in runoff water following land application. The total C varied directly with the ratio of sugarcane and cabbage wastes in the manure but was inversely related to the duration of composting. Extractable K, Ca, Mg, and Na increased whereas trace elements concentrations decreased with time of composting. The higher availability of basic plant nutrients and reduced availability of heavy metals in the mature compost are valuable attributes for safe use in sustainable agricultural production.  相似文献   
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