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51.
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   
52.
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   
53.
54.
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   
55.
Aquaculture International - The present study assessed the toxic effect of super-paramagnetic iron oxide nanoparticles (SPIONs) on haemato-immunological responses, antioxidant capacity, oxidative...  相似文献   
56.
The morphology of tongue in straw-coloured fruit bat from tropical forests was evaluated in relation to frugivorous diets and in comparison with other species that consumes other food types. Gross, stereomicroscopy, scanning electron microscope and histological methods were used. The tongue was relatively long with round tip, which closely fitted into oral cavity. Five types of mechanical papillae included crown-like and trifid filiform papillae. Also bulky, cone-shaped papillae and long conical papillae were identified. These mechanical types also showed variations in shape, size and number of processes of papillae. Transitional forms of these mechanical papillae were present. Fungiform papillae with taste pores were interposed amongst filiform types in apex and body; three ovoid-shaped vallate papillae were in triangular arrangement on root and displayed taste pores. Some bulky, cone-shaped papillae surrounded the vallate papillae. Histologically, mechanical filiform types showed highly keratinized stratified squamous epithelium and dense connective tissue core with secondary papillae. Taste buds appeared in fungiform and vallate papillae. Neutral and acidic secretions were identified in lingual glands of root. The presence of prominent filamentous processes of filiform papillae and conical papillae of the tongue in conjunction with gustatory papillae ensures adaptation to copious fruit diets. The gross morphometric and histometric parameters of the tongue did not differ remarkably from previous values obtained for some fruit bats with comparable weight. This investigation showed similarities with fruit bats such as large flying fox and Egyptian fruit bat and reflect common diet and feeding habits but varied from insectivorous and nectivorous bats.  相似文献   
57.
Grain size plays a significant role in rice, starting from affecting yield to consumer preference, which is the driving force for deep investigation and improvement of grain size characters. Quantitative inheritance makes these traits complex to breed on account of several alleles contributing to the complete trait expression. We employed genome-wide association study in an association panel of 88 rice genotypes using 142 new candidate gene based SSR (cgSSR) markers, derived from yield-related candidate genes, with the efficient mixed-model association coupled mixed linear model for dissecting complete genetic control of grain size traits. A total of 10 significant associations were identified for four grain size-related characters (grain weight, grain length, grain width, and length-width ratio). Among the identified associations, seven marker trait associations explain more than 10% of the phenotypic variation, indicating major putative QTLs for respective traits. The allelic variations at genes OsBC1L4, SHO1 and OsD2 showed association between 1000-grain weight and grain width, 1000-grain weight and grain length, and grain width and length-width ratio, respectively. The cgSSR markers, associated with corresponding traits, can be utilized for direct allelic selection, while other significantly associated cgSSRs may be utilized for allelic accumulation in the breeding programs or grain size improvement. The new cgSSR markers associated with grain size related characters have a significant impact on practical plant breeding to increase the number of causative alleles for these traits through marker aided rice breeding programs.  相似文献   
58.
Detection of infectious hypodermal and hematopoietic necrosis virus (IHHNV) in shrimp is complicated by the fact that certain virus-related sequences are integrated into the genome of Penaeus monodon in some parts of the world, which has been reported so far from Africa and Australia. In this study, we evaluated the highly specific and sensitive diagnostic primer sets for detection of infectious IHHNV and integrated virus-related sequence in 177 samples of P. monodon from India. A nested primer set, IHHNV648F/R and IHHNV309F/R was used to specifically detect infectious IHHNV and not the virus-related sequences. IHHNV was detected in 67.4% postlarvae (PL) and 34% adult samples using this primer set. The OIE recommended primers IHHNV392F/R and IHHNV389F/R gave positive reaction for 86.7% PL and 67% adult samples, while the primer pair 77012F and 77353R gave positive reaction with 46.7% PL and 20% adult samples. These primers were found to detect virus-related sequence integrated into the shrimp genome. The analysis of virus-related sequence by MG831F/R primers showed that 33.7% PL and 31.7% adult shrimp possessed Type A virus-related sequence. 22.8% PL and 10.5% adults had both IHHNV and Type A virus-related sequence. Cloning and sequencing 832 bp virus-related sequence from P. monodon from India revealed presence of five shrimp DNA markers between 439 and 825 bp. This study is the first conclusive report on the presence of Type A virus-related sequence in P. monodon from India.  相似文献   
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