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981.
Rafiqul Islam Harendra Kumar Gyanendra Singh Binsila B. Krishnan Sahadeb Dey 《Veterinary research communications》2017,41(3):201-209
The study was planned to see if there is any important and significant changes in the PMN function in cows suffering from postpartum reproductive diseases (PRD). Blood sampling was done from 41 pregnant cows on 15 days prepartum (?15d), calving day (0d), 15 days (15d) and 30 days (30d) postpartum and thorough gynaecological examination was performed on 0d, 15d, 30d and 45d for diagnosis of PRD like retained placenta (RP), clinical metritis (CM), clinical endometritis (CE) and delayed involution of uterus (DIU). The heparinised blood was used for isolation of PMN leukocytes for estimation of superoxide (SO), hydrogen peroxide (H2O2) and enzyme myeloperoxidase (MPO) activity in each group of cows. The SO production (ΔOD) was greater for normal (0.19 ± 0.05) than cows suffering from RP (?0.12 ± 0.09), CM (?0.15 ± 0.13) and CE (?0.07 ± 0.05) at -15d. The mean value was greater for normal cows (0.12) than the cows with PRD (0.05 to 0.9) at 30d. The H2O2 production was greater for normal than cows with PRD at all sampling days and significantly greater than cows with RP and CE at 15d (p < 0.01) and 30d (P < 0.05). The MPO activity (μmol/1 × 107) was greater for normal (18.77 ± 1.27) than for RP (12.52 ± 2.57) and CM (11.31 ± 3.30) cows on 0d. The depressed capability of the PMN from the cows with PRD to produce SO, H2O2 and MPO during the periparturient period indicated their association with the development of RP, CM and CE. 相似文献
982.
Vivek Joshi V. K. Gupta U. Dimri O. R. Vinodh Kumar D. K. Sharma A. G. Bhanuprakash 《Tropical animal health and production》2017,49(3):497-501
Twelve screened cases of bovine respiratory disease (BRD) in calves were enrolled. Six of the calves were treated intramuscularly with sodium ceftiofur (1 mg/kg), and six were treated with nebulised sodium ceftiofur (1 mg/kg). Comparative evaluation of the two therapeutic modalities was based on repetitive analysis of hematological profile of calves on days 0, 5, and 10 post-therapy. The mortality rate in the group of calves treated with the nebulised sodium ceftiofur was significantly (p?<?0.001) lower, and their clinical and hematological parameters returned to normal significantly (p?<?0.001) faster than in calves treated intramuscularly. Nebulisation of sodium ceftiofur is the most effective treatment in calves with BRD under field conditions. Nasal lavage fluid analysis indicating a high rise of neutrophil count and macrophages may be used as an alternative method to detect pulmonary inflammation in BRD-affected calves. 相似文献
983.
White grubs, Leucopholis spp. are subterranean pests of arecanut grown in South India. Grub infestation leads to yellowing, stem tapering, and crown size and yield reduction. Use of chemical insecticide to mage the white grubs gives varying degree of success. Hence an attempt was made to screen newer and safer insecticides. Imidacloprid (LC50 at 120 h = 16.849 ppm on III instar larvae), chlorpyriphos (LC50 = 14.242) and bifenthrin (LC50 = 12.797 ppm) were identified as effective insecticides. Evaluation of these insecticide in the field over two year period indicated the following efficacy in reducing larval population: chlorpyriphos @ 4 kg a.i/ha (83.31%) > bifenthrin @ 4 kg a.i./ha (82.83%) > imidacloprid @ 0.24 kg a.i./ha (75.84%) > bifenthrin @ 2 kg a.i./ ha (74.26%) > chlorpyriphos @ 2 kg a.i./ha (69.15%) > chlorpyriphos @ 1 kg a.i./ha (61.79%) > imidacloprid @ 0.12 kg a.i./ha (56.54%) > bifenthrin @ 1 kg a.i./ha (54.34%) > imidacloprid @ 0.06 kg a.i./ha (41.47%). Bifenthrin in soil persisted for a longer period than chlorpyriphos. On the day of application, 59.46 ppm bifenthrin residue was recovered from soil. On 10th day, it was 7.29 ppm which decreased to 2.59 ppm on 30th day and was beyond detection limit on 65th day. Chlorpyriphos exhibited a rapid degradation in the initial stage; 27.46 ppm residue on the day of application, which further reduced to 0.964 ppm on 10th day, and was below the detection limit on the 30th day. Growth of Trichoderma harzianum was not affected by bifenthrin even up to 40 ppm concentration. However, chlorpyriphos affected the growth of Trichoderma at higher than 5 ppm dose. Similarly, imidacloprid inhibited the colony growth from 2 ppm onwards. Having high lipophylic property and contact toxicity, bifenthrin would be an ideal alternative insecticide to chlorpyriphos for the management of white grubs in palm garden, which is safe and long persisting. 相似文献
984.
V. M. Malathi Sushil Kumar Jalali Vazhakkala Jose Lyju R. Gandhi Gracy Ravi Prabhakar More Rangasamy Anandham Apoothy Thulasi Thiruvengadam Venkatesan 《Phytoparasitica》2017,45(5):683-693
Nilaparvata lugens (Stål) is one of the major pests of rice throughout tropical and temperate Asia. Indiscriminate use of insecticides for suppressing N. lugens has resulted in the development of resistance to multiple insecticide classes, causing frequent control failures in the field. Analysis of gut bacterial diversity within an insect host is the initial step towards understanding the ecological roles of the symbionts. Present study aimed to survey the bacterial diversity associated with laboratory-reared (insecticide-susceptible) and field-collected (insecticide-resistant) populations of N. lugens by culture-dependent and PCR-Denaturing Gradient Gel Electrophoresis (DGGE) methods. Seventeen bacterial isolates were obtained by the culture-dependent method. Molecular characterization using the 16S rRNA gene and phylogenetic analysis revealed that the isolates belonged to Firmicutes and Proteobacteria. Taxonomic assignment placed these isolates into seven families representing 10 genera. Enterobacteriaceae was the most dominant family with its occurrence in four out of the five populations studied. The DGGE profiles indicated a low complex gut bacteria associated with N. lugens with limited number of bands. The Shannon-Wiener index ranged from 0.898 in insecticide-susceptible population to 0.946–1.035 in resistant populations. Sequencing and phylogenetic analysis revealed that the DGGE bands belonged to Firmicutes, Proteobacteria and Bacteriodetes. Results of this study illustrated that gut bacterial community associated with N. lugens is dominated by Proteobacteria and Firmicutes. Present findings could provide the basis for future work on the possible role of the bacterial symbionts in insecticide resistance and to formulate potential resistance management strategies. 相似文献
985.
R. M. Nair M. Götz S. Winter R. R. Giri V. N. Boddepalli A. Sirari T. S. Bains G. K. Taggar H. K. Dikshit M. Aski M. Boopathi D. Swain A. Rathore V. Anil Kumar E. C. Lii L. Kenyon 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(2):349-364
The segmentation of symptoms during image analysis of diseased plant leaves is an essential process for detection and classification of diseases. However, there are challenges involved in the task, many of them related to the variability of image and host/symptom characteristics and conditions. As a result of those challenges, the methods proposed in the literature so far focus on a specific problem and are usually bounded by tight constraints regarding image capture conditions. This research explores a new automatic method for segmenting disease symptoms on plant leaves that was designed to be applicable in a wide range of situations. The proposed technique employs only color channel manipulations and Boolean operations applied on binary masks, thus being simpler and more robust compared to many previously described automatic methods. Its effectiveness is demonstrated by tests performed over a large database containing images of 77 different diseases of 11 plant species. A comparison with manual segmentation is also presented, further reinforcing the advantages of the proposed approach. 相似文献
986.
Parthenium hysterophorus (Asteraceae) is known as one of the most aggressive invasive weeds, causing severe economic, environmental, human and animal health problems in India and around the world. During a series of extensive surveys for natural enemies of P. hysterophorus, a leaf spot pathogen was isolated from the affected parts of the parthenium following the standard isolation techniques using potato dextrose agar (PDA) and parthenium dextrose agar (PeDA) media. Koch's postulates were performed and found satisfactory for the isolate and proved to be pathogenic to this weed. On the basis of cultural, morphological and molecular characteristics, the pathogen was identified as Alternaria sp. PMK2. The growth of the pathogen was studied on eight selected media and it exhibited varying degrees of growth on different media. Phytotoxicity of fungal cultural filtrates was also confirmed on parthenium leaves in laboratory conditions. Due to the virulent nature of the isolated pathogen, it may be selected for further studies to develop mycoherbicide for control of this devastating weed. 相似文献
987.
Sana Tabanda Saeed B. Kumar A. K. Shasany A. Samad 《Journal of General Plant Pathology》2017,83(5):333-336
Whitefly-transmitted begomovirus induces leaf curling and stunting of Mentha arvensis (Kosi) and is responsible for heavy economic losses in and around Lucknow, India. The complete genome was amplified, sequenced and assembled as 2759 bp long, with 1376 bp betasatellite molecule. Because no DNA-B amplicon was detected, the virus was classified as “Old World begomovirus” with the characteristic seven ORFs; two ORFs (AV1, AV2) in the V-sense and five ORFs (AC1–AC5) in the C-sense. BLASTn and phylogenetic analysis showed highest similarity (98%) with chilli leaf curl India virus (ChiLCINV). This is the first report of ChiLCINV infection in M. arvensis (Kosi) from India. 相似文献
988.
989.
Qin Ran Delara Akhter Yang Chengcong Ujjal Kumar Nath Jamal Eshag Jin Xiaoli Shi Chunhai 《水稻科学》2018,25(6):297-307
Grain shape is one of the important agronomic traits, which is closely related to the yield of rice. A new rice mutant, named small and round grain (srg1), was isolated from an indica cultivar Zhenong 34 by ethyl methane sulfonate (EMS) mutagenesis. The microscopic analysis showed that the cell length of spikelet in srg1 was decreased compared with that in wild type (WT), which caused the grain length short. Meanwhile, the grains of srg1 were wider than those of WT because of the increased cell layers in spikelet in the lateral direction. Therefore, the inhibition of cell expansion and increased cell proliferation collectively led to the small and round grain. By map-based cloning, the gene SRG1 was located on the short arm of chromosome 9, which encodes a kinesin-4 protein, represented by the gene LOC_Os09g02650. A single nucleotide polymorphism, occurred in the 16th exon of SRG1, led to premature translation stop in mutant. The cell cycle-related genes were up-regulated in srg1, which conferred that SRG1 controlled grain width through the cell proliferation. Since the role of SRG1 in regulating grain shape was not clarified well before, it is valuable to explore the mechanism of grain development. This study could, hence, provide a morphogenesis and molecular basis for elucidating the function of SRG1, as well as a new germplasm resource for the further study of grain development. 相似文献
990.
Alokesh Kumar Ghosh 《Aquaculture International》2018,26(2):405-417
A study was conducted in a recirculating aquaculture system (RAS) to assess the growth performance, body composition, fatty acid profile, and nutrient accumulation in different tissues of shrimp using two feeding levels (10 and 16 g/kg0.8/day). The shrimp PL25 was nursed in the nursing tank for 2 months and stocked in six grow out tanks (ten individuals in each 30 L tank). A commercial feed with 42.7% protein was used over a 16-h period per day. After 4 weeks, the final average weight when fed 16 g/kg0.8/day was 9.7 g which was not significantly different from a final weight of 8.6 g achieved when feeding 10 g/kg0.8/day. The protein and energy content increased in high feeding level whereas moisture, crude fat, and ash content decreased with feeding level (P?>?0.05). With the high feeding level, the fatty acid content increased in the eye, muscle, and whole body, with eye containing the highest concentration. The isotopic ratio of δ13C was enriched with feeding level in the muscle and whole shrimp whereas the ratio of δ13C was depleted in the viscera with feeding level. The fraction of δ15N was enriched with decreasing feeding level and highest value was found in the muscle than in the whole shrimp and viscera. 相似文献