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91.
All‐male monosex culture of Macrobrachium rosenbergii (De Man) has emerged as a popular practice in India, especially in the state of Andhra Pradesh. A study was conducted to compare the economics of all‐male, mixed and all‐female culture in 15 adjacent, rectangular ponds of 4000 m2 each by stocking juveniles previously reared in a nursery for 60 days. The experiment was conducted using a completely randomized design with three treatments; T1 (all male), T2 (mixed) and T3 (all female), and five replicates for a period of 5 months after the nursery phase. Statistical analysis showed highly significant (P<0.01) differences among the three types of culture. The cost of production was estimated and the economic feasibility of the culture methods was evaluated by cost‐return and partial budgeting analysis. The average weight, productivity and specific growth rate were the highest for all male culture, being 80.92±2.41 g, 1532 kg ha?1 and 1.97±0.02 respectively. All‐female culture registered significantly higher survival (89.16±0.77%) and the best apparent feed conversion ratio of 1.26±0.02. The economic analysis revealed that all‐male monosex culture of M. rosenbergii was 63.13% and 60.20% more profitable than mixed and all‐female cultures respectively.  相似文献   
92.
Fusarium wilt, caused by Fusarium oxysporum Schlechtend.: f. sp. ciceris (Padwick) Matuo & K. Sato, is a major production problem in many countries. A study was conducted to develop an integrated management of Fusarium wilt of chickpea using genotypes, sowing dates (January as early sowing and March/April as spring sowing) and fungicide seed treatments under natural infested plots in research plots and farmers’ fields 2007–2009 cropping seasons. In most cases, sowing date and fungicides did not affect disease parameters and seed yield. Chickpea genotypes showed significant differences in seed yield but different responses for disease parameters. Averaged over locations and seasons, the rate of disease development was higher in early (0.035 units day?1) than spring (0.023 units day?1) sowing. Chickpea genotypes showed different responses in affecting rate of disease development and cumulative wilt incidence in early and late sowing periods. Higher mean seed yield (1.3 t ha?1) was recorded in early than late sowing (1.0 t ha?1) of chickpea. The average seed yield reduction due to spring sowing ranged from 9% to 60% and highest yield losses were observed in FLIP-97–706 and Ghab-3. This study showed that integrating January sowing with genotypes having good levels of resistance for Fusarium wilt and Ascochyta blight helps farmers to narrow chickpea yield gaps in Syria.  相似文献   
93.
A 7-year-old castrated male French Bulldog was examined for chronic large intestinal enteropathy. A colonic mass and thickened rectal mucosa were identified, and histopathologic examination of endoscopic biopsy specimens disclosed eosinophilic proctitis with large (5-20 μm), irregularly shaped, pauciseptate hyphae that were Gomori methenamine silver and periodic acid-Schiff positive. Amplification and sequencing of ribosomal DNA extracted from paraffin-embedded tissues yielded a sequence with 97% identity to GenBank sequences for Basidiobolus ranarum. After itraconazole, terbinafine, and prednisone administration, clinical signs resolved rapidly, and sonographic lesions were largely absent after 6 weeks. Treatment was discontinued by the owner 15 weeks after diagnosis. Three weeks later, the dog collapsed acutely and was euthanized. Necropsy identified metastatic islet cell carcinoma and grossly unremarkable colorectal tissues. However, histopathology of the rectum disclosed multifocal submucosal granulomas with intralesional hyphae morphologically similar to those previously observed. This report is the first to describe medical treatment of gastrointestinal basidiobolomycosis in a dog.  相似文献   
94.
The aim of the study was to evaluate the effects of varying concentrations of ethylenediaminetetraacetic acid (EDTA) on blood samples from White Fulani breed of cattle and West African Dwarf goat from Nigeria. Sample sizes of 20 animals were used for both species. Different concentrations of EDTA (2, 4, 8 and 16 mg/ml) were used. The packed cell volume (PCV), red blood cell (RBC) and haemoglobin (Hb) concentration of blood samples collected from White Fulani breed of cattle and West African Dwarf goat into bottles containing 16 mg/ml of EDTA were significantly lower (P < 0.05) than those samples collected from the same animals into bottle containing 2 mg/ml (control). Similarly, the PCV, RBC and Hb values of the West African Dwarf goats in bottles containing 8 mg/ml of EDTA were significantly lower than those of the samples in the control (2 mg/ml). This study has shown that high concentration of EDTA as an anticoagulant can lead to a false erythrocytic index especially the PCV. In collecting blood samples for evaluation of haematological parameters, therefore, the blood volume/anticoagulant ratio must be strictly adhered to prevent error in the evaluated parameters in cattle and goats. Taken together, there is tendency for haemolytic anaemia to occur in blood sampled at higher concentration of anticoagulants in West African Dwarf goat than in White Fulani breed of cattle.  相似文献   
95.
Differences in perceptions and knowledge of crop diseases constitute a major obstacle in farmer–researcher cooperation, which is necessary for sustainable disease management. Farmers’ perceptions and management of crop diseases in the northern Ethiopian Regional State of Tigrai were investigated in order to harness their knowledge in the participatory development of integrated disease management (IDM) strategies. Knowledge of disease etiology and epidemiology, cultivar resistance, and reasons for the cultivation of susceptible cultivars were investigated in a total of 12 tabias (towns) in ten weredas (districts). Perception of diseases involved both scientific and spiritual conceptual frameworks. Of the more than 30 crop diseases recorded on the major crops in the region, only rusts and powdery mildews (locally called humodia) and a few root rots were considered by farmers to be important. Farmers’ awareness of other diseases was extremely low; some highly damaging but less conspicuous diseases, such as faba bean chocolate spot and chickpea ascochyta blight (also called humodia), were not regarded by farmers as disease but as problems caused primarily by excessive soil moisture. Considering that some of these “unrecognized” diseases can cause complete yield loss and genetic erosion in epiphytotic years, there is an urgent need for bringing together farmers’ and scientists’ knowledge to complement each other. Even when farmers had access to disease-resistant or disease-tolerant cultivars, they grew susceptible local varieties because of multiple criteria including earliness, good yield in years with low humodia severity, suitability for home consumption, market demand/quality, and low soil fertility and land management requirements. Farmer innovation and knowledge were evident in their use of diverse disease control measures, but these were a mixture of the “useful and the useless.” Our findings stress the necessity for extension workers and researchers to understand and improve farmers’ knowledge of crop diseases, and farmers’ ability to observe and experiment, through the Farmer Field School or a similar experiential learning approach. These insights about farmers’ knowledge of crop diseases provide a basis for further collaborative maintenance of crop genetic diversity, development of germplasm, and IPM-related research in Africa.
Mathew M. AbangEmail:
  相似文献   
96.
Tart cherries are a particularly rich source of anthocyanins. Evidence indicates that dietary intake of anthocyanins is inversely associated with arterial stiffness. We conducted an open-label randomised placebo controlled study to determine whether a tart cherry juice concentrate (Cherry Active®) reduced arterial stiffness, inflammation and risk markers for cardiovascular disease in 47 healthy adults (30–50 years). Participants consumed 30 ml of cherry concentrate diluted to a volume of 250 ml with water or the same volume of an energy matched control drink daily for six weeks. Measurements were taken at baseline and at the end of the intervention. There was no effect of the intervention on arterial stiffness (P?=?0.218), c-reactive protein (P?=?0.220), systolic blood pressure (P?=?0.163), diastolic blood pressure (P?=?0.121), total cholesterol (P?=?0.342) and high density lipoprotein cholesterol (P?=?0.127). At the end of the intervention, plasma antioxidant capacity (measured as the ferric reducing ability of plasma (FRAP)) was significantly higher in the intervention group than the control group (P?=?0.012). We conclude that a tart cherry juice concentrate rich in anthocyanins has no effect on arterial stiffness, c-reactive protein and risk markers for cardiovascular disease, but evokes a minor increase in antioxidant status in healthy adults.  相似文献   
97.
98.
A one-way random effects model is considered for the log-transformed shift-long personal exposure measurements, where the random effect in the model represents an effect due to the worker. Following a previous approach, we address a hypothesis-testingproblem involving the proportion of workers for whom the mean exposure exceeds the occupational exposure limit. A confidence interval is constructed for the relevant parameter of interest, following the idea of a previously presented generalized confidence interval. The confidence bound is used for the purpose of testing hypotheses, and the performance of the test is numerically in vestigated. It turns out that the test exhibits satisfactory performance regardless of the sample size, in particular, for small samples. A similar procedure is then employed for testing hypotheses concerning the overall mean exposure. The results are illustrated using examples.  相似文献   
99.
100.
Alkali treatment coupled with high pressure defibrillation and acid treatment have been tried on banana fibers obtained from the pseudo stem of the banana plant Musa sapientum. The structure and morphology of the fibers have been found to be affected on the basis of the concentration of the alkali and acid and also on the pressure applied. Steam explosion in alkaline medium followed by acidic medium is found to be effective in the depolymerization and defibrillation of the fiber to produce banana nanowhiskers. The chemical constituents of raw and steam exploded fibers were analyzed according to the ASTM standards. Structural analysis of steam exploded fibers was carried out by FTIR and XRD. The fiber diameter and percentage crystallinity of the modified fibers were investigated using X-ray diffraction studies. Characterization of the fibers by SFM and TEM supports the evidence for the development of nanofibrils of banana fibers.  相似文献   
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