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31.
Behera SP Mishra N Vilcek S Rajukumar K Nema RK Prakash A Kalaiyarasu S Dubey SC 《Comparative immunology, microbiology and infectious diseases》2011,34(2):189-196
Previous studies have shown that bovine viral diarrhoea virus type 1 (BVDV-1) subtype b is predominantly circulating in Indian cattle. During testing for exotic pestiviruses between 2007 and 2010, BVDV-2 was identified by real time RT-PCR in two of 1446 cattle blood samples originating from thirteen states of India. The genetic analysis of the isolated virus in 5′ UTR, Npro, entire structural genes (C, Erns, E1 and E2), nonstructural genes NS2-3 besides 3′ UTR demonstrated that the nucleotide and amino acid sequences showed highest similarity with BVDV-2. The entire 5′ and 3′ UTR consisted of 387 and 204 nucleotides, respectively, and an eight nucleotide repeat motif was found twice within the variable part of 3′ UTR that may be considered as a characteristic of BVDV-2. The phylogenetic analysis revealed that the cattle isolate and earlier reported goat BVDV-2 isolate fall into separate clades within BVDV-2a subtype. Antigenic typing with monoclonal antibodies verified the cattle isolate also as BVDV-2. In addition, cross-neutralization tests using antisera raised against Indian BVDV strains circulating in ruminants (cattle, sheep, goat and yak) displayed significant antigenic differences only between BVDV-1 and BVDV-2 strains. This is the first identification of BVDV-2 in Indian cattle that may have important implications for immunization strategies and molecular epidemiology of BVD. 相似文献
32.
Rajkumar U Sharma RP Padhi MK Rajaravindra KS Reddy BL Niranjan M Bhattacharya TK Haunshi S Chatterjee RN 《Tropical animal health and production》2011,43(6):1129-1136
The juvenile growth and carcass traits were evaluated in a 4 × 4 full diallel crossing involving four colored broiler chicken
lines viz., Naked neck (NN), Dwarf, Punjab Broiler-1 (PB-1), and Punjab Broiler-2 to study the performance and crossbreeding
parameters. The data on 2,280 chicks were analyzed using least squares techniques to assess the effect of genetic group, and
the significant traits were further analyzed for crossbreeding parameters. Genetic group had significant influence on the
body weights and carcass traits. The cross of PB-1 × NN recorded significantly (p ≤ 0.05) higher body weight at 6 weeks of age. The data revealed that general combining ability (GCA), specific combining
ability (SCA), maternal ability (MA), sex-linked effect (SE), and purebred effects significantly influenced the growth and
carcass traits in the broiler crosses. The crossbred PB-1 × NN showed positive heterosis for growth as well as carcass traits.
The results suggest that GCA, SCA, SE, and MA are important in the inheritance of the body weights and carcass traits indicating
the presence of both additive and nonadditive genetic variation along with reciprocal effects. Therefore, pure line selection
along with development of specialized sire and dam lines followed by crossing will improve the growth performance and benefit
the poultry farmers. It is concluded that PB-1 as a male line and NN as a female line performed significantly higher, therefore,
may be used for improving the performance of colored broilers. 相似文献
33.
Jang HW Felker DA Bark CW Wang Y Niranjan MK Nelson CT Zhang Y Su D Folkman CM Baek SH Lee S Janicka K Zhu Y Pan XQ Fong DD Tsymbal EY Rzchowski MS Eom CB 《Science (New York, N.Y.)》2011,331(6019):886-889
The formation of two-dimensional electron gases (2DEGs) at complex oxide interfaces is directly influenced by the oxide electronic properties. We investigated how local electron correlations control the 2DEG by inserting a single atomic layer of a rare-earth oxide (RO) [(R is lanthanum (La), praseodymium (Pr), neodymium (Nd), samarium (Sm), or yttrium (Y)] into an epitaxial strontium titanate oxide (SrTiO(3)) matrix using pulsed-laser deposition with atomic layer control. We find that structures with La, Pr, and Nd ions result in conducting 2DEGs at the inserted layer, whereas the structures with Sm or Y ions are insulating. Our local spectroscopic and theoretical results indicate that the interfacial conductivity is dependent on electronic correlations that decay spatially into the SrTiO(3) matrix. Such correlation effects can lead to new functionalities in designed heterostructures. 相似文献
34.
S. Adhikari Ajaz Ahmad Naqvi K. C. Pani Bindu R. Pillai J. K. Jena N. Sarangi 《Journal of the World Aquaculture Society》2007,38(1):161-168
Abstract.— The effect of either manganese or iron on survival, growth, and feeding of giant river prawn, Macrobrachium rosenbergii (De-Man), juveniles was studied in two separate experiments. Survival rates of M. rosenbergii juveniles (4.58 ± 0.48 g) following 60-d exposure to 0.01 (control), 0.3, 0.6, and 1.2 mg/L of total manganese (Mn) were 100, 93.3 ± 3.4, 83.3 ± 4.3, and 83.3 ± 4.3%, respectively, while the same were 100, 83.3 ± 3.6, 73.3 ± 3.3, and 63.3 ± 4.7%, respectively, at the total iron levels of 0.02 (control), 0.32, 0.65, and 1.2 mg/L. Average daily growth of the prawn was significantly ( P < 0.05) lower at 0.3 mg/L and higher levels of total manganese compared to control (0.01 mg/L). Average growth of the prawn exposed to 0.65 and 1.2 mg/L total iron was significantly lower ( P < 0.05) than in control (0.02 mg/L iron) and 0.32 mg/L treatments after 60 d of exposure. Feed utilization was significantly ( P < 0.05) reduced in M. rosenbergii juveniles exposed to 0.3 mg/L and higher levels of manganese. Feed utilization was significantly ( P < 0.05) reduced in the prawns at all the iron treatments compared to control (0.02 mg/L iron). The accumulation of Fe and Mn was minimum in the muscle and maximum in the hepatopancreas of the prawns. 相似文献
35.
A. Sarangi C. A. Madramootoo P. Enright H. Chandrasekharan 《Water, air, and soil pollution》2005,168(1-4):267-288
Spatial data analysis tools for predicting the variability of non-point source pollutants minimize the time, effort and cost involved in extensive and exhaustive real field data measurements. In this study, exploratory data analysis, fitting of semivariogram models, and kriging techniques of geostatistics were used to develop the spatial variability map of soil phosphorous saturation (P sat) percentage over the St-Espirit watershed (2610 ha), located in Quebec, Canada. The P sat measured values for the 281 geo referenced land parcel units (LPU) within the watershed were interpreted and analyzed using the ArcGIS® tool. The geostatistical extension module of ArcGIS® was used for exploratory data analysis, semivariogram model fitting, and development of a P sat prediction map using the ordinary kriging technique. Using these geostatistical procedures and adjustment of lag sizes and lag intervals representing the data sets, it was estimated that the spherical semivariogram model fitted well to represent the P sat variability with residual sum square (RSS) of 0.0003 and coefficient of determination (R 2) of 0.98. Further, the developed model was used to predict the P sat variability over the St. Esprit watershed using the 1605 geo-referenced LPU locations. The generated spatial variability map was geo-spatially processed with the natural drainage network and land use feature classes of the watershed to ascertain the phosphorous loading and locate vulnerable LPUs for phosphorous management. It was observed that the P sat levels were higher at the up stream locations and near the drainage channels than the locations close to watershed outlet. Also, the land pockets with more than 60% agricultural land use resulted in supra-optimal P sat values (10% > P sat < 20%), out of which 8.5 to 16.3 ha agricultural land of the St. Esprit watershed exhibited critical agro-environmental threshold P sat values (P sat > 20%). It was also revealed that, around 23.5% of the watersheds cropped area has reached these threshold levels which necessitate judicious P input management. 相似文献
36.
Girigowda Manjunatha Sathyanaraya Niranjan‐Raj Geetha N Prashanth Shantharaj Deepak Kestur N Amruthesh Hunthrike S Shetty 《Pest management science》2009,65(7):737-743
BACKGROUND: The nature and durability of resistance offered by chitosan and the involvement of nitric oxide (NO) in chitosan‐induced defence reactions in pearl millet against downy mildew disease were investigated. RESULTS: It had previously been reported that chitosan seed priming protected pearl millet plants against downy mildew disease. Further elucidation of the mechanism of resistance showed that chitosan seed priming protects the plants systemically. A minimum 4 day time gap is required between the chitosan treatment and pathogen inoculation for maximum resistance development, and it was found to be durable. Chitosan seed priming elevated NO accumulation in pearl millet seedlings, beginning from 2 h post‐inoculation, and it was found to be involved in the activation of early defence reactions such as hypersensitive reaction, callose deposition and PR‐1 protein expression. Pretreatment with NO scavenger C‐PTIO and nitric oxide synthase (NOS) inhibitor L‐NAME before pathogen inoculation reduced the disease‐protecting ability of chitosan, and defence reactions were also downregulated, which indicated a possible role for NO in chitosan‐induced resistance. CONCLUSION: Protection offered by chitosan against pearl millet downy mildew disease is systemic in nature and durable. Chitosan‐induced resistance is activated via NO signalling, as defence reactions induced by chitosan were downregulated under NO deficient conditions. Copyright © 2009 Society of Chemical Industry 相似文献
37.
Tanpure T Dubey PK Singh KP Kathiravan P Mishra BP Niranjan SK Kataria RS 《Tropical animal health and production》2012,44(7):1587-1592
Leptin gene has been found to be associated with various economic traits including milk production and fat quality in dairy animals. In the present study, we investigated genetic variations in intron 1 region of leptin gene in riverine buffaloes (Bubalus bubalis) using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and sequencing methods and associated them with milk traits. The study revealed three SSCP variants A, B and C among a total of 301 buffaloes from nine breeds. The frequency of variant C was found invariably high among all the breeds except in Marathwada buffalo. Variant A was found to be absent in Chilika, Nili-Ravi, Nagpuri and Pandharpuri breeds and also had the lowest frequencies in Mehsana, Jaffarabadi, Murrah and Toda breeds. Sequencing of SSCP variants revealed a total of five polymorphic sites, with three haplotypes. Statistical analysis revealed significantly high fat percentage at 150?days in SSCP variant B in Mehsana buffaloes. However, the associations of SSCP variants of leptin gene with total milk yield, 305?days milk yield and total fat yield were found to be non-significant. The present study is the first report on association analysis of leptin gene polymorphisms with milk production and milk quality traits in river buffalo. 相似文献
38.
Forty five micromutant lines of blackgram variety PU-30, developed by single and combination treatments with Gamma-rays, ethyl
methane sulphonate (EMS), N-methyl-N-nitroso guanidine (NG) and maleic hydrazide (MH) were evaluated for yield and component
traits. The mutant lines showed significant differences in all 9 traits indicating that the different mutagenic treatments
were effective in inducing changes in all the quantitative characters, though magnitude, direction and frequency of changes
varied with treatments. Genetic divergence among the mutants and the parent was estimated by D2 analysis.100-seed weight, plant height and pod length had high contribution to genetic divergence indicating induction of
more micromutations in these traits. The genetic diversity D2 estimates among the 45 mutant lines and the parent were significant indicating the effectiveness of mutagenic treatments
in isolation of mutant lines with diverse changes in multivariate traits from the parent. Using Tocher’s method the mutants
grouped in to 11 diverse genetic clusters. 31 of the 45 mutant lines grouped into 10 different clusters away from the parent.
These lines not only exhibited genetic diversity from the parent but also among themselves. The mutant lines derived from
the same mutagenic treatment often grouped into different clusters indicating that there was no mutagen specific trend in
clustering. On the basis of D2 values and character complementation, hybridization of mutant line PM 3-3 with PN 3-2 or PGN 2-2 is expected to produce promising
and desirable segregants in subsequent generations. The use of index selection on multiple traits including yield proved to
be an effective and efficient method for selection of high yielding productive mutant lines such as PE2-3, PGN 2-3, PGN 2-2,
PGM 2-2, PG2-1 and PG 3-2. These productive mutants showed changes in some growth and productivity traits from the parent
variety and had 38.5 to 28.7 % yield superiority over parent. Three of these six mutants were derived from combined treatments
and other three from single treatment with Gamma-rays or EMS. 相似文献
39.
水稻产量及其相关性状的数量性状位点(QTL)鉴定(英文) 总被引：2，自引：0，他引：2
Deshmukh Rupesh Sonah Humira Tiwari Anshuman Mahatman Krityanand Jadhav Srikrishna Kadam Suhas Kesawat Mahipal Reddy Niranjan Deshmukh Nilesh Verulkar Satish 《广西农业科学》2008,39(5)
由于大部分水稻育种的最终目标是获得高产、稳产,因此对于育种工作者来说．水稻产量及其构成因素 是重要的性状。在大田试验中,采用随机区组设计,设两个重复,对CT9993-5-10-1-M × IR62266-42-6-2杂交而得 的144份水稻品系DH群体的产量及其主要农艺性状的数量性状位点(QTLs)进行定位。采用MAPMAKER/QTL 1．1软件进行区间定位并估计每个QTL的表型方差的百分比,以LOD阈值>2．4来确定一个QTL的有无.试验鉴 定出与6个水稻农艺性状如千粒重、单株产量、株高、穗长、粒宽、粒长宽比有关的23个QTLs,这些QTLs将有助于 提高水稻产量,并有利于了解水稻产量性状的遗传调控. 相似文献
40.
Phosphorus (P) is the limiting nutrient responsible for the development of algal blooms in freshwater bodies, adversely impacting the water quality of downstream lakes and rivers. Since agriculture is a major non-point source of P in southern Quebec, this study was carried out to investigate P transport under subsurface and naturally drained agricultural fields with two common soil types (clay loam and sandy loam). Monitoring stations were installed at four sites (A, B, C and D) in the Pike River watershed of southern Quebec. Sites A-B had subsurface drainage whereas sites C-D were naturally drained. In addition, sites A-C had clay loam soils whereas sites B-D had sandy loam soils. Analysis of data acquired over two hydrologic years (2004-2006) revealed that site A discharged 1.8 times more water than site B, 4 times more than site C and 3 times more than site D. The presence of subsurface drainage in sandy loam soils had a significant beneficial effect in minimizing surface runoff and total phosphorus (TP) losses from the field, but the contrary was observed in clay loam soils. This was attributed to the finding that P speciation as particulate phosphorus (PP) and dissolved phosphorus (DP) remained relatively independent of the hydrologic transport pathway, and was a strong function of soil texture. While 80% of TP occurred as PP at both clay loam sites, only 20% occurred as PP at both sandy loam sites. Moreover, P transport pathways in artificially drained soils were greatly influenced by the prevailing preferential and macropore flow conditions. 相似文献