Characteristics of the spatio-temporal network of cattle movements in France over a 5-year period     

Bhagat Lal Dutta  Pauline Ezanno  Elisabeta Vergu 《Preventive veterinary medicine》2014

A good knowledge of the specificities of the animal trade network is highly valuable to better control pathogen spread on a large regional to transnational scale. Because of their temporal dynamical nature, studying multi-annual datasets is particularly needed to investigate whether structural patterns are stable over the years. In this study, we analysed the French cattle movement network from 2005 to 2009 for different spatial granularities and temporal windows, with the three-fold objective of exploring temporal variations of the main network characteristics, computing proxies for pathogen spread on this network, which accounts for its time-varying properties and identifying specificities related to the main types of animals and farms (dairy versus beef). Network properties did not qualitatively vary among different temporal and spatial granularities. About 40% of the holdings and 80% of the communes were directly interconnected. The width of the aggregation time window barely impacted normalised distributions of indicators. A period of 8–16 weeks would suffice for robust estimation of their main trends, whereas longer periods would provide more details on tails. The dynamic nature of the network could be seen through the small overlap between consecutive networks with 65% of common active nodes for only 3% of common links over 2005–2009. To control pathogen spread on such a network, by reducing the largest strongly connected component by more than 80%, movements should be prevented from 1 to 5% of the holdings with the highest centrality in the previous year network. The analysis of breed-wise and herd-wise subnetworks, dairy, beef and mixed, reveals similar trends in temporal variation of average indicators and their distributions. The link-based backbones of beef subnetworks seem to be more stable over time than those of other subnetworks. At a regional scale, node reachability accounting for time-respecting paths, as proxy of epidemic burden, is greater for a dairy region than for a beef region. This highlights the importance of considering local specificities and temporal dynamics of animal trade networks when evaluating control measures of pathogen spread.  相似文献   

Stem and leaf rust resistance in wild relatives of wheat with D genome (Aegilops spp.)     

V. K. Vikas  M. Sivasamy  J. Kumar  P. Jayaprakash  Sundeep Kumar  R. Parimalan  Arun Kumar  Kalyani Srinivasan  J. Radhamani  Sherry Rachel Jacob  Mamata Yadav  Jyotisna Rani  I. S. Bisht  D. C. Bhandari  Sunil Archak  M. Dutta  R. K. Tyagi  K. C. Bansal 《Genetic Resources and Crop Evolution》2014,61(4):861-874

Resistance to stem rust and leaf rust in five D genome species of wheat viz., 267 accessions of Aegilops tauschii Coss., 39 of Ae. cylindrica Host, 17 of Ae. ventricosa Tausch, 4 of Ae. crassa Boiss. and 8 of Ae. juvenalis (Thell.) Eig were evaluated at adult plant stage. Two hundred and thirty nine (90 %) accessions of Ae. tauschii, 30 (77 %) of Ae. cylindrica, 16 (94 %) of Ae. ventricosa, 3 (75 %) of Ae. crassa Boiss. and 5 (62.5 %) of Ae. juvenalis were resistant to stem rust pathotypes prevalent in South India at Wellington under field condition. Invariably, all the accessions of the five species were resistant to leaf rust pathotypes. Quantitative measurement of disease using area under the disease progress curve revealed the slow progress of disease in the resistant accessions compared to susceptible check (Agra Local). Since all the five species have D genome, it could be concluded that the genes present in D genome might play a vital role in leaf rust resistance, but in case of stem rust resistance wide range of differential response was noticed. Among the species evaluated, Ae. tauschii was exploited to a larger extent, followed by Ae. ventricosa and Ae. cylindrica for leaf and stem rust resistance because of the homology of D genome with hexaploid bread wheat. While, Ae. crassa and Ae. juvenalis could not be utilized so far, possibly due to partial homology which makes the transfer of traits difficult. So, these species have considerable potential as a source of rust resistance and may enhance the existing gene pool of resistance to stem and leaf rusts.  相似文献   

Exploitation of wild annual Cicer species for widening the gene pool of chickpea cultivars          下载免费PDF全文

Mohar Singh  Krishna Kumar  Ishwari S. Bisht  Manoranjan Dutta  Mukesh K. Rana  Jai C. Rana  Kailash C. Bansal  Ashutosh Sarker 《Plant Breeding》2015,134(2):186-192

Introgression of unadapted genes from the wild Cicer species could contribute to the widening of genetic base of important traits such as yield, yield attributes and resistance to major biotic and abiotic stresses. An attempt was made successfully to intercross two wild annual Cicer species with three cultivated chickpea cultivars. Four interspecific cross‐combinations were made, and their true hybridity was ascertained through morphological and molecular markers. These cross‐combinations were also studied for some important quantitative traits under real field conditions. The range, mean and coefficient of variation of agro‐morphological traits were assessed in the parental lines, their F₁ and F₂ generations to determine the extent of variability generated in cultivated chickpea varieties. A high level of heterosis was recorded for number of pods/plant and seed yield/plant in F₁ generation. Three cross‐combinations of ‘Pusa 1103’ × ILWC 46, ‘Pusa 256’ × ILWC 46 and ‘Pusa 256’ × ILWC 239 exhibited substantially higher variability for important yield‐related traits. The present research findings indicate that these wild annual Cicer species can be easily exploited to broaden the genetic base of cultivated gene pool for improving seed yield as well as adaptation.  相似文献   

Litter decomposition and nutrient release in relation to atmospheric deposition of S and N in a dry tropical region   总被引：1，自引：0，他引：1  

Raj Kumar Singh  Raman Kumar Dutta  Madhoolika Agrawal   《Pedobiologia》2004,48(4):305-311

Temporal and spatial variations in litterfall, leaf litter decomposition and nutrient release were quantified along an air pollution gradient around an industrial area in a dry tropical region of India. Significant differences were found in litterfall between the sites. Litter decomposition rates also significantly varied among the study sites. Litter decomposition was faster at sites away from the industrial region with coal-fired power plants. The concentrations of N and P increased, whereas that of Ca and SO₄-S decreased in decomposing litter over time. The nutrient release pattern was also modified by atmospheric deposition. Concentrations of SO₂ and NO₂ were negatively correlated with relative mass loss. Turnover time of nutrients, except SO₄-S in decomposing litter was maximal at the site receiving highest atmospheric depositions. The study documents that industrial emissions significantly modified nutrient cycling in adjacent terrestrial ecosystems.  相似文献   

Impact of boron fertilization on boron fractions at different crop growth stages in cauliflower_cowpea_okra sequence in an inceptisols of North East India     

Ingudam Bhupenchandra  Anjali Basumatary  Samiron Dutta  Laishram Kanta Singh  Namita Datta 《Journal of plant nutrition》2020,43(8):1175-1188

Abstract

A field experiment was conducted at Horticultural Experimental Farm, Assam Agricultural University, Jorhat during the year 2015–17 to assess the impact of boron fertilization on dynamics of boron fractions in soil and crop yields in cauliflower–cowpea–okra cropping sequence. Five levels of boron (0, 0.5, 1.0, 1.5 and 2.0?kg ha^?1) along with the recommended dose of NPK fertilizer were applied in soil in cauliflower once in each 2 years (2015–17) of experimentation to assess the direct effect of boron fertilization, while cowpea and okra were grown as a suceeding test crop to study the residual effects of boron fertilization in the cropping sequence. Among the different levels of boron, the highest content of all the boron fractions in soil was recorded at rate of 2?kg B ha^?1 at different crop growth stages for all the three crops. Progressive decrease in content of all the boron fractions with crop ageing was noticed. The content of different boron fractions in soil follows the order readily soluble boron (RSB)<oxide bound boron (OXB)<organic bound boron (ORBB)<specifically adsorbed boron (SAB) <residual boron, respectively. The boron level of 2?kg B ha^?1 was found to prominent in increasing the yield in all the crops. In respect of contributions of different boron fractions to yield of crops, oxide bound boron(2.10) was found to be the highest contributor of cauliflower yield, while the residual boron (1.10), contributed the highest to cowpea yield and organic bound boron fraction (1.24) was found to be most prominent contributor of boron in leveraging okra yield.  相似文献   

“家禽微量元素营养”专栏五：微量元素及其生物利用率的重要性     

张贤群  景秦汉 《国外畜牧学(猪与禽)》2009,29(2):10-11

在对不同来源的微量元素进行比较时,关键问题是要考虑其生物利用率.另外,对铬元素要有新的认识.  相似文献   

Detection of serum antibodies against Ehrlichia risticii in Potomac horse fever by enzyme-linked immunosorbent assay   总被引：8，自引：0，他引：8  

S K Dutta  R M Rice  T D Hughes  P K Savage  A C Myrup 《Veterinary immunology and immunopathology》1987,14(1):85-92

An indirect enzyme-linked immunosorbent assay (ELISA) was developed which was specific and sensitive in detecting antibodies to Ehrlichia risticii in Potomac horse fever (PHF). The ELISA antibody titers were correlated with the indirect fluorescent antibody (IFA) titers. E. risticii propagated in human histiocyte culture was purified on renografin gradient and the band of the organisms at a density of 1.182 g/ml was used as antigen. ELISA antibody titers were determined through computer assisted analysis, the observed antibody titers were derived by serial serum dilutions and using a resultant standard curve the predicted antibody titers were obtained from a single serum dilution. The standard curve had a correlation coefficient of 0.8975. The observed and predicted antibody titers were in good agreement, as the respective titers fell within a two-fold range. There was a good correlation between ELISA and IFA test results, but the ELISA titers were several times higher. In experimental infections of horses produced with the infected equine whole blood and the Ehrlichia infected macrophage culture, the antibodies were first detected in two weeks and one week postinoculation (PI), respectively. In both cases the titers reached a peak in about 4 weeks PI with a mean titer of 1:16558 and 1:4030, respectively. The antibody titers of the convalescent sera of field cases of PHF were comparatively lower than the experimentally infected horses.  相似文献   

In vitro interference between equine herpesvirus types 1 and 2   总被引：2，自引：0，他引：2  

S K Dutta  A C Myrup  S R Thaker 《American journal of veterinary research》1986,47(4):747-750

Interference between equine herpesvirus types 1 (EHV-1) and 2 (EHV-2) was studied in equine dermis (ED) monolayer cell cultures and equine lymphocyte cultures. Cell cultures were infected with EHV-2, and after a short incubation period, the cultures were superinfected with EHV-1. At various intervals, different measurements of EHV-1 expression in dually infected cultures, compared with those in cultures infected with EHV-1 alone, were studied. In dually infected ED cell cultures, the EHV-1 cytopathic effect, EHV-1 titer, and EHV-1 enzyme-linked immunosorbent assay antigen titer were maximally reduced to values of 40%, 58.5%, and 54.9%, respectively, at postsuperinfection hour (PSIH) 36. Values of these EHV-1 expressions were subsequently increased at PSIH 48. However, thymidine kinase activity was reduced to a maximum of 67.3% reduction at PSIH 48. In dually infected lymphocyte cultures, the EHV-1 titer, EHV-1 infective centers, EHV-1 enzyme-linked immunosorbent assay antigen titer, and thymidine kinase activity were maximally reduced to values of 77.4%, 78.7%, 98.3%, and 72.9%, respectively, at PSIH 24. These reductions of EHV-1 expressions were completely abrogated at PSIH 48 to 72. In both cell culture systems, a marked interference of EHV-1 by EHV-2 was observed; this was transient in the lymphocyte cultures, but was more prolonged in ED cell cultures. This interference appeared not to be interferon mediated. The multiplication of EHV-2 in the dually infected ED cell cultures appeared unaffected.  相似文献   

Giant cell pneumonia in an aborted calf.     

B C Nayak  A T Rao  S N Panda  N K Dutta 《The Indian veterinary journal》1979,56(4):262-264

  相似文献   

Variability in Mucuna pruriens L. germplasm for L-Dopa, an anti parkinsonian agent     

Archana P. Raina  J. B. Tomar  M. Dutta 《Genetic Resources and Crop Evolution》2012,59(6):1207-1212

Mucuna pruriens L. (Fabaceae) is a popular Indian medicinal plant, which has long been used in traditional Ayurvedic system of Indian medicine for diseases including parkinsonism. The seeds of M. pruriens contain 3,4-dihydroxyphenyl-L-alanine (L-dopa) as a major constituent, an intermediate precursor of the neurotransmitter dopamine. L-dopa extracted from seeds of Mucuna is more effective as drug than the synthetic counterpart. The plant is widely distributed throughout the India and in other parts of the tropics including Central and South America. The present study was aimed to screen thirty-eight accessions of Mucuna germplasm collected from different geographical regions of India for L-dopa content, an effective drug used for Parkinson’s disease. The L-dopa content in seeds of M. pruriens was quantitatively analyzed by high performance thin-layer chromatography (HPTLC) at 280?nm wavelength. Results indicated wide variability among thirty-eight accessions of M. pruriens for seed characters like seed colour, size and shape. The L-dopa content in seeds of M. pruriens ranged between 3.29 and 5.44?% (on dry weight basis) among different germplasm collections augmented from various parts of India. Promising accessions identified having high L-dopa content were IC551549 (5.44?%), IC551514 (5.41?%), IC331536 (5.40?%), IC552857 (5.36?%), IC385844 (5.32?%) and IC439197 (5.32?%). Due to the economic importance of the drug, these promising M. pruriens accessions can be exploited for large scale cultivation for their pharmacological important constituents mainly L-dopa content.  相似文献