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111.
112.
The counter-immunoelectrophoresis test (CIEPT) was compared with the rose bengal plate test (RBPT) and the serum agglutination test (SAT) in the diagnosis of brucellosis in 241 sheep. The total number of animals positive by one or more of the tests used was 106. Sixty animals were positive by all tests, while 87, 79 and 80 were positive by CIEPT, RBPT and SAT respectively. Based on the assumption that animals with an SAT titre of 40 I.U./ml or above were true positives, the CIEPT had a sensitivity of 82.5% and a specificity of 78.3% compared to 96.5% and 87% respectively, demonstrated by the RBPT. CIEPT might be used in flocks without clinical evidence of ram epididymitis if a test to supplement RBPT were required; but it would only partially replace SAT. Sera positive in RBPT but negative in CIEPT would have to be tested by SAT. With this combination, only about 22% of sera positive in RBPT would need to be further tested by SAT. 相似文献
113.
Basal stem rot disease caused by the white‐rot fungus Ganoderma boninense is a major threat to the oil palm industry, and hence, the ability to detect infections at an early stage of development is desired. In this study, a headspace solid‐phase microextraction (HS‐SPME) method coupled with gas chromatography–mass spectrometry (GC‐MS) was employed to analyse the volatile organic compounds (VOCs) released from G. boninense cultures and infected oil palm wood. We examined VOCs released from three types of samples: G. boninense mycelium, oil palm wood and oil palm wood colonized by G. boninense. This preliminary study led to the tentative identification of 57 VOCs, including alcohols, alkanes, volatile acids, ketones, aldehydes, esters, sesquiterpenes and polycyclic aromatic hydrocarbon groups. Aliphatic compounds with eight‐carbon atoms, such as 1‐octen‐3‐ol, 3‐octanone, 1‐octanol and (E)‐2‐octenal, were the most abundant constituents of the Ganoderma samples, whereas furfural and hexanal were the major compounds detected in the oil palm wood samples. Chemometric analyses using cluster heat maps and principal component analyses were used to discriminate between the VOC profiles. The results indicated that the novel method described here could be used to detect Ganoderma disease and, more generally, for chemoecological studies of plant–pathogen interactions. 相似文献
114.
Forest policy and sustainable forest management in Bangladesh: an analysis from national and international perspectives 总被引:2,自引:0,他引:2
This paper includes a review of international sustainable forestry development followed by an analysis of forest policies
in Bangladesh. There have been four different government forest policies in Bangladesh since 1894. The first two forest policies
(1894 and 1955) were exploitative in nature. Most of the regulatory documents were developed during the first two policy periods.
The third forest policy instituted in 1979 by the sovereign Bangladesh government had contradictory elements and mutually
inconsistent policy statements. It addressed for the first time forestry extension through mass motivation campaign. Current
forest policy formulated in 1994 has been considered to be the most elaborate policy in the history of the country. Under
this policy, participatory social forestry has been institutionalized in Bangladesh. The analysis shows that, although it
is possible to attain the stated policy targets, progress is slow and is blocked on several fronts. A number of identified
technical, managerial and logistical problems are hindering policy and program implementation. In addition, corruption contributes
to the observed problems. The real strength of Bangladesh forestry is locally based, participatory forestry, co-management
of protected areas and highly motivated people who increasingly recognize the need for a healthy forest ecosystem that will
provide future economic stability. Because it is the rich homestead forests of Bangladesh that generate the majority of commercial
forestry products, it is important that education continues at the grass-roots level. In addition, educated forestry and environment
professionals have been identified as the future driving forces towards better, and sustainable, forest management. Results
of this study make it clear that Bangladesh and other developing countries are not presently in a position to accept and adopt
internationally derived forest policies due to inadequate institutional support, political instability and poor governance.
Therefore, along with development of criteria and indicators of sustainable forest management and forest certification, international
policy scientists must consider institutional development, professional skill development, identification and adoption of
indigenous technology and long-term financial support in developing countries. Without these, all international processes,
policies and directives will be of little value and produce few substantive results. 相似文献
115.
Mohammad Shaheed Hossain Chowdhury ;Md. Abdul Halim ;Nur Muhammed ;Farhana Haque ;Masao Koike 《林业研究》2008,19(3):245-251
A study was conducted to explore the traditional utilization pattern and indigenous management practices of wild date palm (Phoenix sylvestris Roxb) in the rural agrarian regions of Bangladesh. A multistage sampling method with 10% intensity and a semi-structured questionnaire were used for the study. The farmers manage the palm mainly for sap production with which sugar based secondary goods are manufactured. The sap is either used fresh as drink or after some sort of processing as molasses and/or alcoholic beverage. Seven diversified sites support the palm as its habitat and most palms (20.40%) occur in orchards. Besides growing naturally, the palm is also established in orchards using the wildings as the staple planting material. Although the medium category farmers own most of the palms (33%), a considerable portion (28.68%) of it is managed by the landless farmers, who earn a substantial livelihood from the palms. The farmers practice their own indigenous wisdom in every stage of the palm's maintenance from planting through tapping for sap collec- tion to the processing of products. If managed more scientifically on a sustainable basis with the collaboration of farmers' indigenou~ knowledge, this familiar palm could be able to support the rural economy of the country to a great extent. Side by side, it would also be able to contribute to the richness of biodiversity in the region. 相似文献
116.
Mohammad Shaheed Hossain Chowdhury Md. Mizanur Rahman Masao Koike Nur Muhammed Kazi Mohammad Salahuddin Md. Abdul Halim Narayan Saha Md. Parvez Rana Md. Jahirul Islam 《Small-Scale Forestry》2010,9(1):93-105
Throughout the world ornamentation of body with mehedi (Lawsonia inermis L.) leaf paste, with the trade name ‘henna body art’ is becoming increasingly popular. The worldwide increasing demand of
mehedi leaf encourages many countries to adopt commercial farming of the plant. Farmers living in central Bangladesh recently
commenced small-scale mehedi farming, primarily with the purpose of meeting national demand. A total of 182 farmers are engaged
in mehedi farming and a study was conducted among 36 of them (a 20% random sample) to explore indigenous management techniques,
marketing, livelihood potential and constraints of the enterprise. Farming was reported to be the major primary occupation
of the study area. An average of 0.05 ha land of the respondents was used for mehedi cultivation, which constituted 16.7%
of their average farm land. The farmers applied their own indigenous technology in every aspect of the farming, using branch
cuttings as the only propagation material. The financial analysis indicated that mehedi farming is a profitable and attractive
option for rural livelihoods [with an estimated net present value of Tk (Bangladeshi currency unit, 1 US $ = 68 Taka (as of
May, 2009).) 179,500 for 0.1 ha plantation]. However, the enterprise faces several constraints, including absence of a nursery
for supplying planting materials, storage and effective marketing facilities, available capital for investment, improved technology,
and above all, government support. If the government extends cooperation by assisting farmers with training, technology, credit
and market development, mehedi farming could become an important revenue-earning enterprise in the small-scale cottage sector
of Bangladesh. 相似文献
117.
Serological types of Pasteurella haemolytica in Kenya 总被引:1,自引:0,他引:1
The 12 known serotypes of P. haemolytica and two biotypes A and T were found to occur in Kenya. Biotype T was more common in disease conditions than biotype A, which was more common in the nasal passages of healthy animals. Only biotypes A strains were recovered from cattle and the majority were serotypes 1 and 2, but serotypes 4 and 11 were also isolated. All serotypes were found to occur in sheep and goats, but serotypes 3, 4, 6, 8 and 10 were more commonly associated with pneumonia. It was observed that chickens could harbour both biotypes A and T in pathological conditions. Biotype A serotype 2 was isolated from an adult wildebeest, but the prevalence of P. haemolytica in wild animals needs furter investigation. 相似文献
118.
119.
This experiment was carried out in the framework of a project to develop a viable fish polyculture technology under Bangladeshi conditions that allows simultaneous fish production of small indigenous species for the farmers' family consumption and of large carp species as a cash crop. The objectives of this experiment were to assess the effects on fish performance and on the environment of adding 20% large fish to the basic ‘cash crop’ carp–small fish polyculture consisting of 10 000 fish ha?1 of the large carp rohu Labeo rohita (Hamilton), catla Catla catla (Hamilton) and common carp Cyprinus carpio (L.) at a species ratio 1:1:1, and 15 000 fish ha?1 of each small indigenous fish punti Puntius sophore (Hamilton) and mola Amblypharyngodon mola (Hamilton) (control). The treatment ponds were stocked with additional 2000 large fish ha?1, either all rohu, or all catla, or all common carp, or half rohu and half common carp, or half catla and half common carp. The results obtained and the analysis of interactions through the food web that affect food resource availability of the different fish species and account for the trends and differences observed among treatments confirm the positive effect of common carp on rohu reported in previous experiments and show that a 20% increase in large carps stocking neither affect the survival of the large carps nor reduce harvesting biomass of the small fish for the farmer's family consumption. Increased stocking densities of each large carp species did not significantly reduce its own harvesting weight and mean growth rate, while significantly increased rohu and catla (but not common carp) harvesting biomass and yield. The complex relations between species led to inter‐ and intraspecific competition, which in some treatments increased growth or yield of one species and in other treatments of other species, so that the gains on one species and the losses on the other led to no significant total harvested biomass differences between treatments. Yet, the results herein reported may help farmers to select their species stocking ratios. Thus, if the main target of the farmer is rohu, then a stocking density increase of 10% common carp and 10% rohu would improve rohu growth rate (due to common carp) and result in 50% higher rohu harvesting biomass and yield. If the main target of the farmer is catla, then a 20% increase in catla stocking density would lead to 20% higher catla harvesting biomass. 相似文献
120.
The velocity of compressional waves and electrical resistivity in granite in situ measured in two 3-kilometer boreholes exhibits very little variation with depth, in contrast with the variation predicted from laboratory measurements on dry samples. These observations can be explained either by the absence of small open cracks in the rocks in situ or by the effects of complete saturation with water. The seismic velocities of many granites at shallow depths in the earth's crust may be significantly larger than was previously believed. Other properties are also affected; correction for the effect of cracks on thermal conductivity raises the average heat flow in shield areas by as much as 20 percent. 相似文献