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141.
Endocannabinoids are fatty acid amides (FAE; oleoylethanolamide and anandamide) which have orexigenic, anorexigenic or anti‐inflammatory properties. We examined mRNA expression via qPCR of endocannabinoid receptors (CNR1 and CNR2), enzymes that synthesize FAE (HRASLS5 and N‐acyl phosphatidylethanolamine phospholipase D), enzymes that degrade FAE [fatty acid amide hydrolase (FAAH), N‐acylethanolamine acid amidase (NAAA) and monoglyceride lipase (MGLL)], and the hormone precursor proopiomelanocortin (POMC) in liver at ?14, 7, 14 and 30 days around parturition from cows fed with a control (CON; NEL = 1.34 Mcal/kg) or moderate‐energy (OVER; NEL = 1.62 Mcal/kg) diet during the dry period. Expression of CNR2 and POMC was greater at 7 days in cows fed with OVER because of a decrease in expression between ?14 and 7 days in cows fed with CON. Cows fed with CON had an increase in expression of FAAH, HRASLS5, NAA, MGLL and POMC between 7 and 14 days; for FAAH and HRASLS5, such response led to greater expression at 14 days vs. cows fed with OVER. Cows fed with OVER vs. CON had a approximately twofold increase in expression of MGLL between ?14 and 7 days followed by a gradual decrease through 30 days at which point expression was still greater in OVER vs. CON. FAAH, MGLL and HRASLS5 were the most abundant genes measured. Expression of the hepatic endocannabinoid system and POMC was altered by plane of dietary energy prepartum particularly during the first 2‐week postpartum. Such responses may play a role in the physiological adaptations to the onset of lactation, including energy balance and feed intake. 相似文献
142.
Cauda epididymal spermatozoa were obtained from testicles collected from abattoir(s). The pooled sperm samples were divided into four aliquots. Each aliquot was washed separately with the buffer of respective extender and finally extended with the four extenders viz. egg yolk–citrate (EYC), egg yolk–citrate–fructose (EYCF), Tris–citric acid–egg yolk–fructose (TCEYF) and egg yolk–Mcillvaine glucose (EYMG) and preserved at 4°C. The per cent sperm motility for EYC, EYCF, TCEYF and EYMG at 0 h was 50.83%, 56.67%, 75.00% and 31.67%, respectively, and at 72 h was 24.17% (EYC), 30.83% (EYCF), 51.67% (TCEYF) and 7.50% (EYMG). The corresponding figures for live sperm count at 0 h was 83.17%, 86.33%, 90.42% and 81.75% and at 72 h was 64.75%, 73.92%, 76.00% and 57.67%. The corresponding figures for mean per cent intact acrosome at 0 h was 95.33%, 95.50%, 90.92% and 97.25% and at 72 h was 86.17%, 83.92%, 77.58% and 86.33%. The sperm motility was significantly (p < 0.05) higher for TCEYF at different h of preservation from 0 h through 72 h. The sperm motility, live sperm count and per cent intact acrosome declined significantly (p < 0.05) with the advancement of storage time in all the four extenders. Our study concluded that TCEYF was best out of the extenders studied for preservation of cauda epididymal spermatozoa after double centrifugation and extension at 4°C up to 72 h of preservation. However, EYCF also has better potential for the preservation of cauda epididymal spermatozoa as viability was in close proximity and acrosomal integrity was higher compared with TCEYF extender. 相似文献
143.
Md. Habibur Rahman Most. Jannatul Fardusi Bishwajit Roy Md. Mostafa Kamal Md. Jasim Uddin Mohammed Abu Sayed Arfin Khan 《Small-Scale Forestry》2012,11(2):207-221
Rattan, an important non-timber forest product, is a flexible palm used in weaving baskets or furniture. Rattan is light yet sturdy, making it suitable for furniture that can be moved often. Bangladesh has a large number of rattan-based enterprises. This paper reports a case study carried out in Sylhet City Corporation of north-eastern Bangladesh, exploring the production, financial profitability and marketing of rattan-based products, and the problems and priorities of rattan-based enterprises as well as their potential contribution to employment opportunity. A sample survey was conducted of 58 randomly selected rattan-based enterprises with entrepreneurs personally interviewed using a semi-structured questionnaire. Based on the total investment, the enterprises were divided into large, medium and small categories. Three origins of rattan (Local, Myanmar and Indonesia) and five species were used by the enterprises to produce 29 rattan-based product types. Rattan products were divided into three basic categories, viz. domestic utensils, domestic decorative articles and others for which uses are not specific. Among the three rattan origins, processing cost of local and Myanmar rattan species products was less and more articles were sold than for Indonesia rattan species. Financial analysis indicated that rattan-based enterprises are a profitable and attractive option for local socio-economic development. Entrepreneurs’ views on major problems and issues in rattan-based product trading and suggested measures to improve the condition of rattan-based enterprises also collected. Rattan-based enterprises will generate more domestic revenue, foreign exchange and employment if policies are adopted to provide the enterprises with a reliable source of raw materials and technical and financial assistance from Government to NGOs to sell the products, and expand market facilities in both local and international markets. 相似文献
144.
Khalid Saifullah Khan Tanja Müller Jens Dyckmans Rainer Georg Joergensen 《Biology and Fertility of Soils》2010,46(4):323-331
A pot experiment was carried out to monitor the recovery of a steaming-reduced microbial biomass (C, N, and P) and fungal
ergosterol by sucrose addition. The second objective was to investigate the recovery of a steaming-reduced microbial biomass
by white mustard (Sinapis alba) cultivation and its interactions with microbial residues, freshly formed from sucrose addition. Thirty days after steaming,
the soil microbial biomass C and N was still significantly reduced by 80%, leading to a rather constant microbial biomass
C/N ratio around 7 throughout the experiment. The steaming-induced decreases of microbial biomass P and ergosterol were only
roughly 50%, leading to a decrease in the microbial biomass C/P ratio and an increase in the ergosterol-to-microbial biomass
C ratio. Sucrose addition led to a 25% reduction in the ergosterol-to-microbial biomass C ratio. Mustard cultivation had significant
positive effects on microbial biomass C, N, P, and ergosterol, but the effects were smaller than those of sucrose addition.
Cultivating mustard had no significant effects on the C loss or on the incorporation of sucrose C into the microbial biomass.
In contrast, the application of sucrose led to a significant decrease in the mustard shoot biomass and especially in the mustard
root biomass. 相似文献
145.
Establishment of Protected Areas (PAs), in the face of rapid deforestation, forest degradation and climate change has been one of the key efforts in conservation of biodiversity worldwide in recent times. While Bangladesh has gained a degree of prominence in the world for its successful social forestry programs, the concept of collaborative protected area management is rather new in the country, initiated in 2004 by the Bangladesh Forest Department in five PAs with financial assistance from USAID. Based on empirical evidence from three of the pilot PAs, we examined the achievements and associated challenges and prospects for co-management. Our fieldwork revealed a number of challenges faced by co-management institutions: (1) institutions were dominated by the elite group, overshadowing the voice of the community people; (2) mutual trust and collective performance are key to good governance but had not taken root in the PAs; (3) encroachment onto forest land and subsequent conversion to agriculture remained a serious problem that discouraged forest-dependent people from participating actively in co-management initiatives; (4) legal provisions (including acts, rules and policies) were not clearly and adequately disseminated and understood at the community level; (5) there remained a degree of ambiguity regarding the roles and responsibilities of forest department (FD) and co-management committees (CMC) in field operations, and this was not enhancing transparency and accountability of the overall initiative; (6) the long-term sustainability of co-management institutions was another major concern, as the local intuitional structure was still in a nascent stage, and provisioning of resources (either internally or externally) remained somewhat uncertain. We offer recommendations for improvement. 相似文献
146.
Shisham (Dalbergia sissoo) is an important multipurpose tree with great economic importance, but this tree has been devastated by dieback disease. Seedlings and asexually propagated (cuttings) plants were artificially inoculated with four fungi (Fusarium solani, Botryodiplodia theobromae, Curvularia lunata and Ganoderma lucidum) to evaluate the potential role of these fungi in shisham dieback disease. Results at 2 years revealed that highest disease was caused by inoculation of F. solani (31.39%), followed by B. theobromae (19.042%) and C. lunata (12.22%), but no dieback disease was caused by G. lucidum. During both years, seedlings exhibited greater susceptibility to disease (17.24%) compared to cuttings (7.83%). In particular, F. solani caused more disease in seedlings (46.18%) compared to cuttings (16.61%). With the F. solani inoculations, maximum disease rate was observed at 8 weeks post‐inoculation both in seedlings (77%) and in cuttings (31%), but the maximum disease increase was observed at 4–5 weeks post‐inoculation. Analysis of variance showed significant differences among the different fungi and also between seedlings and cuttings. F. solani can be considered as a major fungal pathogen contributing to dieback disease of shisham, and asexual propagation can reduce the severity of dieback. 相似文献
147.
M. Arif N. W. Zaidi Q. M. R. Haq Y. P. Singh S. Khan U. S. Singh 《Forest Pathology》2013,43(6):478-487
Sissoo (Dalbergia sissoo), commonly known as shisham, is amongst the finest woods of South Asia, but ‘wilt’ disease has caused a rapid decline in this species. The cause of the disease remains uncertain. The aim of this study is to identify the causal agent of the disease and characterize isolates made from diseased trees, based on genomic data and variations in virulence. Samples of infected roots, stems and the ooze exuded from infected trees were obtained from plants showing symptoms in different geographical regions of India for the isolation of microorganisms. Isolates were used to inoculate healthy plants. Based on the morphological characteristics, genus‐ and species‐specific PCR, and in silico analysis of 5.8S rDNA‐ITS regions, of the 38 fungal isolates, 24 and 14 were identified as Fusarium solani and Fusarium sp., respectively. In a pathotyping study, eighteen F. solani isolates, isolated from roots and stem parts of symptomatic plants, induced typical wilt symptoms when inoculated through soil and roots on D. sissoo seedlings of 1–15 months in age. The population of F. solani was the highest in infected roots and the lowest in parts of stems, gradually decreasing with height, and was isolated constantly up to approximately 40% height of the seedling. F. solani isolates used in inoculations were successfully re‐isolated from the rhizosphere, infected roots and wilted stems, as confirmed using isolate‐specific DNA fingerprints. Molecular phylogenies based on rDNA‐ITS sequences showed that the 38 isolates fell into 2 groups. Group I comprised of F. solani isolates from D. sissoo and F. solani sequences in the NCBI GenBank database, whereas group II included Fusarium isolates other than F. solani. These results are helpful in developing integrated control measures for this highly variable pathogen and to establish a base for future population studies. 相似文献
148.
1. A study was designed to investigate the comparative effect of supplementary vitamin E, vitamin C, probiotics and dietary crude protein concentration on semen traits and seminal plasma biochemical parameters in male broiler breeders after Zn-induced moulting. 2. A total of 180 male broiler breeders were induced to moult at 65 weeks of age by mixing ZnO in diet at the rate 3000?mg/kg of feed. After moulting, the males were divided into six groups that were given feed supplemented with: vitamin C (500?IU/kg), vitamin E (100?IU/kg), protein (140?g CP/kg), probiotics (50?mg/kg) and the combination of these components, while one group was kept as a control. Semen samples were collected weekly and semen volume, spermatozoa concentration, motility and dead spermatozoa percentage were determined. Seminal plasma was separated to determine the concentration of total antioxidant capacity (TAC), homocysteine, paraoxonase (PON1), arylesterase, ceruloplasmin, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities. 3. Semen volume was significantly higher in the vitamin E and C groups compared to the control. Spermatozoa motility was higher in the vitamin E group and dead spermatozoa percentage was significantly lower in the vitamin C group compared with the control group. 4. Seminal plasma TAC was higher in the vitamin E group, homocysteine was lower in the vitamin C and E groups. PON1 was higher in the combination group. Arylesterase increased significantly in the vitamin C and combination groups over time. Seminal plasma AST was significantly lower in the vitamin C and E supplemented groups whereas ALT decreased significantly only in the vitamin E group compared with the control. Higher concentrations of ceruloplasmin were observed in the combination group compared with the other treatments. 5. It was concluded that additional vitamin E and C or their combination was the most potent nutrient treatment for improving the semen traits and seminal plasma biochemical characteristics in male broiler breeders after Zn-induced moulting. 相似文献
149.
Feng-lian LÜ Miao-miao HOU Hong-tao ZHANG Asif Khan Muhammad Ayaz Ciren QIANGJIU Chang-lu HU Xue-yun YANG Ben-hua SUN Shu-lan ZHANG 《农业科学学报》2019,18(1):169-178
A high crop yield with the minimum possible cost to the environment is generally desirable. However, the complicated relationships among crop production, nitrogen (N) use efficiency and environmental impacts must be clearly assessed. We conducted a series of on-farm N application rate experiments to establish the linkage between crop yield and N2O emissions in the Guanzhong Plain in Northwest China. We also examined crop yield, partial factor productivity of applied N (PFPN) and reactive N (Nr) losses through a survey of 1 529 and 1 497 smallholder farms that grow wheat and maize, respectively, in the region. The optimum N rates were 175 and 214 kg ha–1 for winter wheat and summer maize, respectively, thereby achieving the yields of 6 799 and 7 518 kg ha–1, correspondingly, with low N2O emissions based on on-farm N rate experiments. Among the smallholder farms, the average N application rates were 215 and 294 kg ha–1 season–1, thus producing 6 490 and 6 220 kg ha–1 of wheat and maize, respectively. The corresponding PFPN values for the two crops were 36.8 and 21.2 kg N kg–1, and the total N2O emissions were 1.50 and 3.88 kg ha–1, respectively. High N balance, large Nr losses and elevated N2O emissions could be explained by the overdoses of N application and low grain yields under the current farming practice. The crop yields, N application rates, PFPN and total N2O for wheat and maize were 18 and 24% higher, 42 and 37% less, 75 and 116% higher, and 42 and 47% less, correspondingly, in the high-yield and high-PFPN group than in the average smallholder farms. In conclusion, closing the PFPN gap between the current average and the value for the high-yield and high-PFPN group would increase crop production and reduce Nr losses or the total N2O emissions for the investigated cropping system in Northwest China. 相似文献
150.
This study was conducted to evaluate the efficiency of diammonium phosphate (DAP), agricultural limestone (lime), and green‐waste compost mixed with 30% treated sewage sludge (GCS) applied alone or in combination as chemical immobilization treatment using tomato as a test crop. Mine waste was collected from an abandoned copper‐mine tailing site at Mynydd Parys, Anglesey (UK). Lime was applied at the rate of CaCO3 equivalent (CCE, pH = 7), DAP at the rate of 23 g P per kg substrate, and 10% by weight, GCS as sole application. Half rate of each amendment was also tested as a combined treatment and an untreated substrate (control). Plant‐available metals (Cd, Cu, Fe, Pb, and Zn) were measured in substrate with conventional diethylenetriaminepentaacetic acid (DTPA) and sequential Ca(NO3)2 extraction. Plant–dry biomass yield was significantly (p < 0.001) increased by the combined application of all the three amendments while sole application of DAP reduced yield by 4‐fold compared to unamended soil probably due to P toxicity. Addition of lime reduced the DTPA‐extractable Cu, Fe, and Zn by 75%, 81%, and 85%, respectively, while Pb availability was reduced by 88% in combined DAP + lime + GCS treatment compared to control. The extraction capacity of DTPA was higher than that of Ca(NO3)2 by 3‐fold for Cu and Fe, 8‐fold for Pb, and 2‐fold for Zn. The leaf‐tissue concentrations of Cu and Fe were reduced by 77% and 83% in the lime + GCS amendment, respectively, while both Pb and Zn were reduced by 89% and 33%, respectively, in substrate treated with the combined application of all three amendments. These results suggest that alkaline amendments (both lime and GCS) were effective in reducing the phytoavailability of Cu, Fe, and Zn while DAP mixed with either GCS or lime was effective in reducing Pb availability. 相似文献