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51.
Biswas S Sanyal A Hemadri D Tosh C Mohapatra JK Manoj Kumar R Bandyopadhyay SK 《Veterinary microbiology》2006,116(1-3):187-193
A total of 18 foot-and-mouth disease virus (FMDV) serotype Asia1 field isolates belonging to two different lineages (including the divergent group) as delineated earlier in VP1-based phylogeny were sequenced in the non-structural 3A and 3C protein-coding regions. The phylogenetic trees representing the regions coding for the non-structural proteins were very similar to that of the structural VP1 protein-coding region. Phylogenetic comparison at 3C region revealed clustering of Asia1 viruses with the isolates of serotypes O, A and C in the previously identified clade. Comparison of amino acid sequences identified lineage-specific signature residues in both the non-structural proteins. Overall analysis of the amino acid substitutions revealed that the 3A coding region was more prone to amino acid alterations than 3C region. 相似文献
52.
Saxena MK Singh VP Kumar AA Chaudhuri P Singh VP Shivachandra SB Biswas A Sharma B 《Veterinary research communications》2006,30(8):851-861
Repetitive extragenic palindromic sequence-based PCR (REP-PCR) was used to characterize 67 field isolates of Pasteurella multocida originating from different animal species and geographical regions of India. REP-PCR was found to be rapid and reproducible
(three repeats were done). These isolates yielded different 23 profiles which were clustered into eight groups. The discrimination
index was moderate (D value 0.83). Somatic and antigenic typing of the isolates did not reveal any correlation with REP-PCR profiles. There was
no host-specific, type-specific, region-specific or pathenogenicity-specific pattern. The REP profiles of isolates obtained
from wild animals were similar to those obtained from domestic animals. Two common bands were present in all the isolates
irrespective of somatic or antigenic types. The results were not comparable with earlier findings, which had shown high discrimination
index and correlation with disease presentation.
Saxena, M.K., Singh, V.P., Kumar, A.A., Chaudhuri, P., Singh, V.P., Shivachandra, S.B., Biswas, A. and Sharma, B., 2006. REP–PCR
analysis of Pasteurella multocida isolates from wild and domestic animals in India. Veterinary Research Communications, 30(8), 851–861 相似文献
53.
The metacommunity concept provides a spatial perspective on community dynamics, and the landscape provides the physical template
for a metacommunity. Several aspects of landscape heterogeneity, such as landscape diversity and composition, and characteristics
of the matrix between habitat patches such as habitat connectivity, and geometry of habitat patches, may moderate metacommunity
processes. These aspects of landscape heterogeneity are rarely considered explicitly in the metacommunity discussion, however.
We propose landscape contrast (i.e., the average dissimilarity in habitat quality between neighboring patches) as a key dimension
of landscape heterogeneity. The concept of landscape contrast unifies discrete and continuous landscape representations (homogeneous,
gradient, mosaic and binary) and offers a means to integrate landscape heterogeneity in the metacommunity concept. Landscape
contrast as perceived by the organisms affects several fundamental metacommunity processes and may thus constrain which metacommunity
models may be observed. In a review of empirical metacommunity studies (n = 123), only 22 % of studies were explicit about their underlying landscape model assumptions, with striking differences
among taxonomic groups. The assumed landscape model constrained, but did not determine, metacommunity models. Integration
and explicit investigation of landscape contrast effects in metacommunity studies are likely to advance ecological theory
and facilitate its application to real-world conservation problems. 相似文献
54.
Rashid HB Chaudhry M Rashid H Pervez K Khan MA Mahmood AK 《Tropical animal health and production》2008,40(6):463-467
The present work was conducted to study the comparative efficacy of two anti-protozoan (babesicidal) drugs on the recovery and health of horses. A total of 80 horses, showing typical clinical symptoms of the disease, were selected for this study; the presence of babesiosis was confirmed through blood smear examination. These animals were divided into two groups i.e. A and B. Horses of Group A, were treated with diminazene diaceturate, while horses of Group B were treated with diminazene aceturate. Efficacy of the drugs was determined by the reversal of clinical signs and a negative blood smear examination. The efficacy of diminazene diaceturate was demonstrated to be 80% while diminazene aceturate was found to have 90% efficacy against babesiosis. 相似文献
55.
Evaluation of sugar and organic acid composition and their levels in highbush blueberries from two regions of China
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ZHANG Jia NIE Ji-yun LI Jing ZHANG Hui LI Ye Saqib FAROOQ Syed Asim Shah BACHA WANG Jie 《农业科学学报》2020,19(9):2352-2361
Sweet and sour are the most important taste of blueberries, and they are produced by sugar and acid, respectively. Their contributions to the taste depend not only on the levels of sugar and acid, but also on the types and relative proportions of sugar and acid. Therefore, it is very important to evaluate the composition and levels of sugar and acid in blueberries. Regional differences and variety diversity also affect the sugar and acid characteristics of fruits. Therefore, this study selected two main producing regions in northern China(Weihai and Yingkou) to examine the sugar and acid characteristics of 11 common blueberry cultivars. The indexes measured included soluble sugars, organic acids, soluble solid content and titratable acidity. The results showed that glucose and fructose were the major sugars, and citric acid and quinic acid were the major organic acids. Correlation analysis showed that glucose, fructose, and sucrose were positively correlated with total sugar content; the citric acid content was positively correlated with the titratable acidity and total organic acids. Titratable acidity, glucose, fructose, sucrose, total sugar content, citric acid, shikimic acid and total acid content of the blueberries varied significantly between regions(P0.05). In general, compared with Weihai blueberries, Yingkou blueberries had higher sugar content and lower acid content. The results of this study may provide useful references for the evaluation of sweet and sour flavors and cultivar selection of blueberries. 相似文献
56.
Context
Ecological processes that shape diversity and spatial pattern of ecological communities are often altered by disturbance. Spatial patterns (spatial autocorrelation) in species diversity are thus expected to change with disturbance.Objective
When examining spatial patterns, ecologists traditionally lump positive and negative spatial autocorrelation into the overall spatial autocorrelation. By contrast, here we aim to understand disturbance effects on both positive and negative spatial autocorrelation of species richness and evenness, which may be related to environmental filtering and restricted dispersal, and to competition, respectively.Methods
For 8 years, we monitored the spatial autocorrelation in species richness and evenness of riparian plant communities in both uncut control and experimentally clearcut sites in the boreal forest of Alberta, Canada. The overall spatial autocorrelation for each of these two indices of diversity was separately decomposed into the components of positive and negative spatial autocorrelations through eigendecomposition of the spatial weighting matrix.Results
Negative spatial autocorrelation in richness and evenness were more pronounced in the clearcut than uncut sites, although positive spatial autocorrelations in all indices of diversity remained unchanged. Effect of disturbance was not detected on the overall spatial autocorrelation.Conclusions
Disturbance increases negative spatial autocorrelation in species richness and evenness, with a stronger increase in evenness than richness, which underscores the importance of competition in structuring post-disturbance riparian communities. Our results also highlight the need for assessing positive and negative spatial autocorrelation and different aspects of diversity separately in understanding disturbance effects on the spatial pattern, or identifying processes from patterns.57.
Krishna Sukumaran Asim K. Pal Narottam P. Sahu Shrinivas Jahageerdar Deepak Khambadakone Dipesh Debnath 《Aquaculture International》2011,19(4):749-763
The present study was conducted to investigate the changes in mineralization and morphology in response to graded levels of
dietary phosphorus in Indian major carp, Catla (Catla catla) fingerlings (av. wt. 4.23 ± 0.87 g). The experimental system constituted of 24 150-L capacity plastic tanks (eight treatments,
three replicates) stocked with 20 fingerlings each. Eight isonitrogenous and isocaloric semi-purified diets (crude protein
35%, crude lipid 8.5%) were formulated with graded levels of phosphorus (0%-control; 0.1; 0.3; 0.5; 0.7; 0.9; 1.1; 1.3; 1.5%)
using KH2PO4. The fish were fed twice daily with the respective feeds for a period of 120 days. The percentage of ash content in whole
body, vertebrae and opercular bones was found to be significantly (P < 0.05) lower in fish fed low levels of dietary phosphorus (T1, T2) in comparison with other treatments. The concentration of phosphorus and calcium was found to be significantly (P < 0.05) lower in whole body, vertebrae and opercula of fish fed low phosphorus diets (T1, T2) relative to treatments with higher levels of dietary phosphorus supplementation. The concentration of magnesium in opercular
and vertebral tissues of T1 group was significantly (P < 0.05) lower than all other groups. The X-ray radiographs did not reveal any skeletal deformities in any of the treatments.
Truss analysis showed absence of significant morphological variations between fish of different treatments. The deficiency
of dietary phosphorus in catla led to significantly lower mineralization of whole body and bone tissues, but the deficiency
was not severe enough to cause skeletal deformities and morphological changes in the fish. 相似文献
58.
Marra MA Jones SJ Astell CR Holt RA Brooks-Wilson A Butterfield YS Khattra J Asano JK Barber SA Chan SY Cloutier A Coughlin SM Freeman D Girn N Griffith OL Leach SR Mayo M McDonald H Montgomery SB Pandoh PK Petrescu AS Robertson AG Schein JE Siddiqui A Smailus DE Stott JM Yang GS Plummer F Andonov A Artsob H Bastien N Bernard K Booth TF Bowness D Czub M Drebot M Fernando L Flick R Garbutt M Gray M Grolla A Jones S Feldmann H Meyers A Kabani A Li Y Normand S Stroher U Tipples GA Tyler S Vogrig R 《Science (New York, N.Y.)》2003,300(5624):1399-1404
We sequenced the 29,751-base genome of the severe acute respiratory syndrome (SARS)-associated coronavirus known as the Tor2 isolate. The genome sequence reveals that this coronavirus is only moderately related to other known coronaviruses, including two human coronaviruses, HCoV-OC43 and HCoV-229E. Phylogenetic analysis of the predicted viral proteins indicates that the virus does not closely resemble any of the three previously known groups of coronaviruses. The genome sequence will aid in the diagnosis of SARS virus infection in humans and potential animal hosts (using polymerase chain reaction and immunological tests), in the development of antivirals (including neutralizing antibodies), and in the identification of putative epitopes for vaccine development. 相似文献
59.
Kuntal M. Hati Ashis K. Biswas Kalikinkar Bandyopadhyay Arun K. Misra 《植物养料与土壤学杂志》2004,167(5):584-590
Post‐methanation effluent (PME) generated through bio‐methanation of distillery effluent, a foul‐smelling, dark colored by‐product of distillery industries, is applied to arable land in some areas near the vicinity of the distillery industries as an amendment. The PME contains considerable amount of organic matter and salt besides its high plant‐nutrient content. The present investigation was conducted for three years during 1999–2002 on soybean‐wheat cropping sequence to evaluate the effect of graded levels of post‐methanation effluent (PME) on soil physical properties and crop productivity in a deep Vertisol of central India. Six application doses of PME viz. S2.5+W0: 2.5 cm PME applied to soybean and wheat on residual nutrition, S2.5+W1.25: 2.5 cm PME to soybean and 1.25 cm to wheat, S5.0+W0: 5 cm PME to soybean and wheat on residual nutrition, S5.0+W2.5: 5.0 cm PME to soybean and 2.5 cm to wheat, S10.0+W0: 10 cm PME to soybean and wheat on residual nutrition, and S10.0+W5.0: 10.0 cm PME to soybean and 5.0 cm to wheat, were compared with 100% recommended NPK+FYM ? 4 Mg ha–1 and control (no fertilizer, manure or PME). The application of PME increased the organic carbon content and electrical conductivity of the soil compared to control and 100% NPK+FYM treatment. The organic C content was maximum in S10.0+W5.0 (11.2 g kg–1) and minimum in control (5.2 g kg–1). Electrical conductivity increased from 0.47 dS m–1 in control to 1.58 dS m–1 in highest dose of PME (S10.0+W5.0). The PME treatments have not affected the soil pH. The application of PME showed a significant improvement in the physical properties of the soil. The mean weight diameter (MWD), percent water‐stable aggregation (% WSA), saturated hydraulic conductivity (Ksat), and water retention (WR) at 0.033 MPa suction were significantly (P < 0.05) more while bulk density (BD) and penetration resistance was significantly less in PME‐treated plots than that of control. The MWD showed a linear and positive relationship (r = 0.89**) with the soil organic C. Soybean recorded significantly higher seed yield at all PME treatments than control. Highest average soybean yield (2.39 Mg ha–1) was recorded in S10.0+W0 but yield decreased significantly in S10.0+W5.0 (2.08 Mg ha–1). In wheat, all the PME‐treated plots except S2.5+W0 yielded significantly higher than control while the 100% NPK+FYM treatment yielded (3.46 Mg ha–1) at par with the S10.0+W5.0 (4.0 Mg ha–1) and S5.0+W2.5 (3.66 Mg ha–1). Fresh application of PME to wheat resulted in significant improvement in grain yield over that grown on residual fertility. Thus, application of PME to arable land, as an amendment, could be considered as a viable option for the safe disposal of this industrial waste. 相似文献
60.
Shil Bikash Lahiri Biswajit Pal Prasenjit Ghosh Amitava Biswas Pradyut Singh Yumlembam Jackie 《Aquaculture International》2022,30(4):2017-2041
Aquaculture International - Most of the adoption studies in catfish culture were restricted to feeding habits, growth rate and morphological studies, neglecting the social factors and adoption of... 相似文献