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121.
This study was carried out to assess the relationship of the status of nodulation (i.e., the number of nodules, their shape and size) in root and biomass production of plant growth parameters (i.e., number of leaves, root and shoot lengths, root biomass and shoot biomass) in Albizia saman and Leucaena leucocephala. The assessment started 60 days after seeding. The study revealed that nodulation response and biomass production in both species showed significant dif- ferences over time (p 〈 0.05) in all variables except in the root-shoot ratio (oven-dry) of L. leucocephala. The study also showed significant differences (p 〈 0.05) in nodule formation and biomass production at the end of the study period be- tween the two species except in the number of nodules and leaves and the green root-shoot ratio. There were strong pos- itive correlations between nodule formation and biomass production, i.e., the number of nodules and the age of plants, the number of nodules and leaves, as well as the number of nodules and biomass (root biomass and shoot biomass) in both species. The results obtained using principal component analysis (PCA) and correlation coefficients of the different characteristics of nodulation and biomass production were similar in both species. The PCA showed that shoot biomass (shoot green weight and shoot oven-dry weight) is positively correlated with PC1 (with an eigenvalue of 7.50) and root length is positively correlated with PC2 (with an eigenvalue of 0.19) in the case of A. saman. In the case of L. leucocephala, the PCA revealed that root biomass (root green weight and root oven-dry weight), shoot biomass and shoot length are also positively correlated with PC1, while nodule formation and the number of leaves are positively correlated with PC2 (with an eigenvalue PC1 of 6.92 and PC2 of 0.49).  相似文献   
122.
Some studies have attributed forest shrinkage to population growth, economic development, conversion of forest land to agricultural use and harvesting of trees for timber and fuelwood. But the statistical support for these hypotheses is not strong. This paper attempts to test the above hypotheses statistically in the case of Bangladesh. Factor analysis extracted 4 important factors—(a) exploitation of forests for timber, fuelwood, tea, and shrimp production, (b) demographic pressure in agriculture, (c) economic development, and (d) expansion of crop lands—as causes of deforestation. The statistical test supports the hypotheses that the exploitation of forests for timber, fuelwood, tea and shrimp production, and conversion of forests to crop lands have a negative influence on forest cover. Economic development and demographic pressure in agriculture are also negatively correlated with forest cover. Results of regression analysis show the conversion of forests to agricultural land is the most important cause of deforestation. Other important causes, in order of their relative importance, are the relative price of forest products, population growth, economic development, demographic pressure in agriculture, increasing production of shrimps, export of tea and shrimps, increasing production of timber and fuelwood, and expansion of tea lands. The statistical tests support the above relationships.  相似文献   
123.
After improvement of hygiene protocols on boots in a bovine operation (farm A) in Ibaraki, Japan in September 2017, mortality of calves and the detection of 4 viral pathogen indicators, including bovine rotavirus A (RVA), became significantly low for one year. Subsequently, in the present study, these indicators and mortality were monitored and confirmed all were still low, except for the detection rate of bovine RVA in calves less than 3 weeks old. The present study aimed to investigate G and P genotypic profiles of RVAs in farm A from 2018 to 2020. Molecular analysis using semi-nested multiplex RT-PCR of positive RVAs (n=122) and sequencing of selected samples revealed the presence of G6, G8, G10, P[1], P[5] and P[11] genotypes and the prevalence of G and/or P combination and mixed infections. The most common combination of G and P types was G10P[11] (41.8%), followed by mixed infection with G6+G10P[5] (11.5%). Phylogenetic analysis of RVAs showed clustering with bovine and other animal-derived RVA strains, suggesting the possibility of multiple reassortant events with strains of bovine and others animal origins. Noteworthy as well is that vaccinated cattle might fail to provide their offspring with maternal immunity against RVA infections, due to insufficient colostrum feeding. Our findings further highlight the importance of RVA surveillance in bovine populations, which may be useful to improving effective routine vaccination and hygiene practices on bovine farms.  相似文献   
124.
Analysis of environmental samples obtained from the Live Poultry Markets (LPMs) of Dhaka City, Bangladesh, has revealed that the highest degree of prevalence of highly pathogenic avian influenza A (HPAI, H5N1), besides other subtypes of the LPAI virus, poses the plausible risk of transmission of these viruses between human and poultry species. The present study was conducted using the OIE risk analysis framework to assess the risk level of each pathway successively. The estimated risk parameters were integrated towards to obtain the overall risk level for each specific HPAI transmission pathway using the matrix adapted by Cristobel Zepeda accompanying other expert consultations. The relevant data obtained from published and unpublished sources, together with survey data of field observations, were used to formulate and confirm the risk pathways and their associated risks. The results revealed that the risk of the release of the HPAI virus was medium when exposure was high. Additionally, the consequence would be considered very high with a medium degree of uncertainty for all parameters. Ultimately, the overall risk for transmission was estimated as medium with a medium degree of uncertainty. The findings of this study reveal that there is a significant threat that HPAI virus transmission could occur among poultry and humans and effectively sustain within the environment of the LPMs. Our findings are primarily focused on public health considerations, the hygienic slaughter of poultry and the relevant cleaning and sanitation practices conducted in the LPMs to support evidence‐based decision‐making processes. The findings of the study have the potential to be used to formulate effective risk reduction measures and can be further adapted in low‐resource settings without major infrastructural changes required of the LPMs. All of which would reduce the risk of HPAI virus release and further lessen the degree of exposure and transmission in established LPMs.  相似文献   
125.
Milk, especially colostrum, contains different kinds of macromolecules abundantly, such as immunoglobulin G (IgG), lactoferrin (Lf), transferrin (Tf), and growth factors. These are essential for the development and maintenance of health, which greatly depends on the absorption and transportation of macromolecules to the target organs. To evaluate the macromolecular transport, and concentrations in plasma and cerebrospinal fluid (CSF), colostrum was fed to newborn calves followed by milk and milk replacer, and maintained up to the 4th week under farm conditions. Plasma and CSF were collected at different times, and were analyzed for Lf, Tf, IgG and iron concentrations. Lf, Tf and IgG concentrations were steeply increased in plasma and CSF after colostrum feeding, and fluctuating patterns were observed during the experiments. Furthermore, intraduodenal administration of bovine Lf alone in young calf experiments revealed that the Lf concentration reached a peak at 4 hr, and was 7 and 4 times higher than preadministration in plasma and CSF, respectively. To explore the transport mechanism of Lf into CSF in young calves, epithelial membranes of the choroid plexus were prepared and a binding assay for Lf receptors (Lf-R) was carried out with 125I-Lf. The saturation kinetics revealed that the Bmax of epithelial membranes was 26.15 nmol/mg protein with a Kd of 0.11 microM, which also showed that Lf-R is saturable and specific. Scatchard plot transformation showed the presence of a single type of Lf-R in the choroid plexus. These results suggest that Lf is transported into the CSF through receptor mediated transcytosis in young calves, and that Lf may play an important role(s) in brain function.  相似文献   
126.
ABSTRACT

This paper discusses fish consumption and preference patterns for fish species by income groups, and by urban/rural divide in Bangladesh, China, India, Indonesia, the Philippines, Thailand, and Vietnam. The analysis is based on primary data collected by the WorldFish Center and its partner institutes by means of a survey of 5,931 households in the selected countries. The FAO database and other published materials were also used to analyze trends in fish consumption. Freshwater fish species constitute a major share in total per capita fish consumption in most of these countries. Pelagic and demersal marine fish are the main contributor to per capita total fish consumption in the countries with longer coastal boundaries (such as Indonesia, the Philippines and Thailand), and in the coastal regions within each country. Results suggest that fish contributes between 15% and 53% of the total animal protein intake in these countries. Fish consumption varies widely with economic position of the households, in terms of both per capita consumption and type of fish species. Per capita fish consumption increases with increase in income. The share of fish protein in total animal protein expenditure is higher for lower income groups, demonstrating their dependence on fish as a source of animal protein. Poor people consume mostly low-price fish and rich people spend a significant portion of their fish budget on expensive fish. Per capita fish consumption is substantially higher in rural areas than in urban areas.  相似文献   
127.
The ethanol leaf extract of Cymbidium aloifolium (L.) was evaluated for its analgesic and antiinflammatory activities. The extract, at the dose of 200 and 400 mg kg(-1) body weight, exerted the analgesic activity by observing the number of abdominal contractions and anti-inflammatory activity against Carrageenin induced paw edema in mice by measuring the paw volume. The ethanolic extract of Cymbidium aloifolium (L.) showed statistically significant (p < 0.05) reduction of percentage of writhing of 33.57 and 61.31% at 200 and 400 mg kg(-1) oral dose, respectively, when compared to negative control. The Ethanolic plant extract also showed significant (p < 0.05) dose dependent reduction of mean increase of formation of paw edema. The results of the experiment and its statistical analysis showed that the ethanolic plant extract had shown significant (p < 0.05) dose dependent analgesic and anti-inflammatory activities when compared to the control.  相似文献   
128.
Parental condition‐dependent offspring fitness is a well‐discussed issue in animal breeding research, while offspring environment and its interaction with parental condition are currently another very interesting topic to investigate the plasticity of phenotypic traits across an environmental gradient. The present study was, therefore, conducted following a half‐sib breeding design to test the effects of (a) paternal body size, (b) offspring feeding strategy (everyday and every other day) and (c) their interactions on fitness‐related traits (e.g., survival, total length and body area) of offspring of a commercially important aquaculture species, the Indian major carp (Labeo rohita). The analysis revealed that paternal body size had significant effects on offspring survival rate and total length, while no significant influence was found in body area. The study also showed that the offspring feeding strategy significantly affected all offspring traits. Interestingly, the study unveiled the significant interactive effects of paternal condition and offspring feeding for offspring survival rate and total length. These findings suggest that paternal size, offspring rearing environment and their interactions can influence offspring fitness‐related traits which are very essential information for the sustainable production of good quality larvae under variable dietary conditions.  相似文献   
129.
The present study aimed to evaluate the effect of organic and inorganic selenium (Se) supplementation on semen quality and blood serum profiles of buffalo bulls. Nine mature buffalo bulls were divided into three groups: control (non‐supplemented); organic Se (10 mg Sel‐Plex®/head twice weekly) and inorganic Se (10 mg sodium selenite/head twice weekly). Semen was collected twice a week for 3 months during Se supplementation. Semen properties were evaluated from fresh ejaculate. Moreover, fructose concentration, aspartate and alanine transaminase (AST and ALT) activities, total protein and total cholesterol were assayed in seminal plasma. Additionally AST, ALT, testosterone and Se levels were determined in the blood serum. Results showed that Se supplementation significantly (P < 0.05) influences the semen parameters during 3 months of treatment. Organic Se significantly (P < 0.05) increased the percentage of viable sperms compared to inorganic Se and the control group. Fructose concentration was significantly higher (P < 0.05) in the seminal plasma of organic Se‐treated bulls. Serum testosterone and Se concentrations were significantly (P < 0.05) increased in the Se supplemented groups than the control group. In conclusion, Se supplementation improved the parameters of buffalo bull semen and more precisely, organic Se was more effective for the improvement of semen quality and some blood components than inorganic Se.  相似文献   
130.
Drought stress is a major limiting factor for crop production in the arid and semi‐arid regions. Here, we screened eighty barley (Hordeum vulgare L.) genotypes collected from different geographical locations contrasting in drought stress tolerance and quantified a range of physiological and agronomical indices in glasshouse trails. The experiment was conducted in large soil tanks subjected to drought treatment of eighty barley genotypes at three‐leaf stage and gradually brought to severe drought by withholding irrigation for 30 days under glasshouse conditions. Also, root length of the same genotypes was measured from stress‐affected plants growing hydroponically. Drought tolerance was scored 30 days after the drought stress commenced based on the degree of the leaf wilting, fresh and dry biomass and relative water content. These characteristics were related to stomatal conductance, stomatal density, residual transpiration and leaf sap Na, K, Cl contents measured in control (irrigated) plants. Responses to drought stress differed significantly among the genotypes. The overall drought tolerance was significantly correlated with relative water content, stomatal conductance and leaf Na+ and K+ contents. No significant correlations between drought tolerance and root length of 6‐day‐old seedling, stomatal density, residual transpiration and leaf sap Cl? content were found. Taking together, these results suggest that drought‐tolerant genotypes have lower stomatal conductance, and lower water content, Na+, K+ and Cl? contents in their tissue under control conditions than the drought‐sensitive ones. These traits make them more resilient to the forthcoming drought stress.  相似文献   
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