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31.
An effort has been made to isolate individual catechin compounds from green tea leaves in their pure form by electrophoresis. In the present study total polyphenol extraction was carried out initially and estimated through spectrophotometric and HPLC methods. Extracted polyphenol was separated on 0.7% agarose gel and visualized at 360 nm. Fragmented individual compounds were gel eluted with methanol and confirmed as (-)-epigallocatechin (EGC), (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), and (-)-epigallocatechin gallate (EGCG) by HPLC. The method developed describes a suitable method for the isolation of valuable molecules in tea.  相似文献   
32.
Mastitis (intramammary inflammation) caused by infectious pathogens is still considered a devastating condition of dairy animals affecting animal welfare as well as economically incurring huge losses to the dairy industry by means of decreased production performance and increased culling rates. Bovine mastitis is the inflammation of the mammary glands/udder of bovines, caused by bacterial pathogens, in most cases. Routine diagnosis is based on clinical and subclinical forms of the disease. This underlines the significance of early and rapid identification/detection of etiological agents at the farm level, for which several diagnostic techniques have been developed. Therapeutic regimens such as antibiotics, immunotherapy, bacteriocins, bacteriophages, antimicrobial peptides, probiotics, stem cell therapy, native secretory factors, nutritional, dry cow and lactation therapy, genetic selection, herbs, and nanoparticle technology-based therapy have been evaluated for their efficacy in the treatment of mastitis. Even though several strategies have been developed over the years for the purpose of managing both clinical and subclinical forms of mastitis, all of them lacked the efficacy to eliminate the associated etiological agent when used as a monotherapy. Further, research has to be directed towards the development of new therapeutic agents/techniques that can both replace conventional techniques and also solve the problem of emerging antibiotic resistance. The objective of the present review is to describe the etiological agents, pathogenesis, and diagnosis in brief along with an extensive discussion on the advances in the treatment and management of mastitis, which would help safeguard the health of dairy animals.  相似文献   
33.
Genetic Resources and Crop Evolution - Grewia tenax (Forssk.) Fiori commonly known as ‘Gangani’, was studied to provide scientific information pertaining to taxonomy, distribution...  相似文献   
34.
ABSTRACT

The present study was to delineate management zones (MZs) in salt affected Mahakalpada block in eastern India by capturing both spatial variability of soil parameters along with satellite derived Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). Grid wise 237 soil samples collected from the study area were analyzed and spatial maps were generated for physicochemical properties, DTPA extractable micronutrients, i.e. iron, zinc, copper, and manganese and major nutrients, i.e. available nitrogen (AN), phosphorous (AP), and potassium (AK). Soil electrical conductivity and AK showed a high CV of 100% and 56.7%, respectively. Principal component analysis was performed using the soil spatial maps, NDVI and EVI maps and only four principal components which produced eigenvalues > 1 and accounting for 75.4% of the total variability were retained for further analysis. Further, fuzzy c-mean clustering was used to delineate the MZs based on fuzzy performance index (FPI) and normalized classification entropy (NCE) was used for identifying the three MZs. There was a significant difference between MZ1 and MZ2 for all the variables except AN and EVI whereas all the variables were significantly different between MZ1 and MZ3 highlighting the usefulness of MZs delineation technique for site-specific nutrient management.  相似文献   
35.

Background

Importance of parasites in ecological and evolutionary interactions is being increasingly recognized. However, ecological data on parasites of important host species is still scanty. We analyze the patterns seen in the faecal parasites of tigers in the Tadoba National Park, India, and speculate on the factors and processes shaping the parasite community and the possible implications for tiger ecology.

Results

The prevalence and intensities were high and the parasite community was dominated by indirect life cycle parasites. Across all genera of parasites variance scaled with the square of the mean and there was a significant positive correlation between prevalence and abundance. There was no significant association between different types of parasites.

Conclusions

The 70 samples analyzed formed 14 distinct clusters. If we assume each of the clusters to represent individual tigers that were sampled repeatedly and that resident tigers are more likely to be sampled repeatedly, the presumed transient tigers had significantly greater parasite loads than the presumed resident ones.
  相似文献   
36.
The status of forest conditions before and after intervention of the forestry projects in community forest in three districts of Nepal is examined. Benefits are observed from the adoption of adaptive collaborative management and collective learning and action research in three sampled districts. The adoption of regular silvicultural treatments has increased the availability of forest products to local users. Moreover, improved forest condition and smallholder livelihoods have improved, as has environmental sustainability. However, the community forestry program has several limitations and shortcomings. Elite capture, social disparity, inequitable benefit-sharing and exclusion of poor and marginalized groups from the community forestry program are notable challenges to be solved in coming years. Special attention is needed to make community forestry inclusive with equitable benefit-sharing and a pro-poor focus.  相似文献   
37.
The effects of extracts of different parts of the perennial tropical plant Balanites aegyptiaca (L) Del., including various solvent extracts of roots, methanol extracts from leaves, fruits, flowers and roots, partially purified saponins obtained from its roots and a standard saponin were studied on the life cycle (adult longevity, number of eggs, crawlers, adults, weight of adults and % wax content) of a laboratory-reared parthenogenic line of the mealy bug, Maconellicoccus hirsutus (Homoptera: Pseudococcidae). Extracts derived from various parts of B. aegyptiaca (leaves, fruits, flowers, and roots in methanol) affected the life cycle of M. hirsutus with a methanol root extract being the most effective at a concentration of 500 μg ml−1. Partially purified saponin of B. aegyptiaca and the commercial bark saponin extract (Sigma) from Quillaja saponaria at a concentration of 500 μg ml−1 were effective in reducing the longevity of M. hirsutus. Significant reductions in oviposition by M. hirsutus were found for all the extracts at a concentration of 500 μg ml−1. Extracts also affected the number of emerging crawlers, number of adults as well as the weight and wax content of emerging adults. These studies suggest that B. aegyptiaca plant extracts and saponins can be useful botanical insecticides for the protection of crops from mealy bugs.  相似文献   
38.
The life cycle of a laboratory reared parthenogenic line of mealybug, Maconellicoccus hirsutus (Green) (Hemiptera: Pseudococcidae) was investigated on six host plants (Lagenaria siceraria var.clavata, Solanum tuberosum L. var. Kufri Chandramukhi, Praecitrullus fistulosus (Stocks) Pangalo var. MTNH1, Cucurbita pepo var. Styriaca, Triticum aestivum L. var. Lokvan, H. rosa sinensis L.) at five constant temperatures (25, 29, 35, 38, 42 °C). The number of emerging crawlers and adults as well as weight of adults varied with host and temperature. P. fistulosus and H. rosa sinensis were suitable hosts for laboratory rearing of M. hirsutus. However, ease of maintenance of P. fistulosus to produce M. hirsutus under laboratory conditions is an additional advantage compared to using green plants such as H. rosa sinensis. Among the range of constant temperatures, 38 °C was found to be the most favourable for the development and survival of M. hirsutus. These results suggest that P. fistulosus fruits are suitable hosts for laboratory rearing and life cycle studies of M. hirsutus.  相似文献   
39.
40.
Studies on parthenogenetic activation of oocytes are important to improve the efficiency of nuclear transfer as artificial activation of oocytes is an essential component of nuclear transfer protocol. The present study was carried out to investigate the effects of different activation methods, culture systems and culture media on in vitro development of zona-free and with-zona parthenogenetic embryos in goat. In case of zona-free parthenogenesis, there was a significant (p < 0.05) increase in cleavage rate and blastocyst yield when oocytes were activated by electrical pulse (76.29 ± 0.52% and 19.07 ± 0.39% respectively) than when Ca-ionophore was used for activation (63.45 ± 0.73% and 14.09 ± 0.65% respectively). The quality of blastocysts was evaluated by determination of cell number and by expression profile of pluripotent related gene Oct-4. No significant (p < 0.05) difference was found in quality of blastocysts produced by different activation methods. In culturing of zona-free parthenogenetic embryos, flat surface (FS) was proved to be the best system. A significant (p < 0.05) decrease in cleavage rate and blastocyst yield was found in Microdrop culture of zona-free embryos (43.67 ± 2.08% and 0.72 ± 0.72% respectively) in comparison to WOW of zona-free embryos (73.88 ± 1.70% and 15.51 ± 1.34% respectively) and FS of zona-free (75.14 ± 0.81% and 23.93 ± 2.71% respectively) as well as with-zona (72.16 ± 1.55% and 18.16 ± 0.68%) embryos. Zona-free flat culture system yielded significantly (p < 0.05) higher blastocyst rate than zona-free WOW system as well as with-zona flat culture system. The zona-free and with-zona parthenogenetic embryos were cultured in three different media — Research Vitro Cleave media from Cook® Australia (RVCL), Embryo Development Medium (EDM) and Modified Synthetic Oviductal Fluid (mSOF). In case of zona-free parthenogenesis, significant (p < 0.05) increase was found in blastocyst development rate in RVCL medium (18.61 ± 1.52%) than EDM (11.29 ± 0.77%) or mSOF (11.53 ± 1.86%). In case of with-zona parthenogenesis, RVCL medium and EDM were found superior to mSOF. The results of the study will be helpful to improve the efficiency of nuclear transfer in goat.  相似文献   
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