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Manickam Pavunraj Chellaiah Muthu Savarimuthu Ignacimuthu Sundaram Janarthanan Veeramuthu Duraipandiyan Nagappan Raja Selvaraj Vimalraj 《Phytoparasitica》2011,39(2):145-150
The effects of crude extracts and an isolated compound from the leaves of milkweed, Pergularia daemia (Forssk) Choiv., on the antifeedant activity against two important lepidopteran pests, Helicoverpa armigera (Hub.) and Spodoptera litura (F.), were studied. Maximum antifeedant activity was recorded in ethyl acetate crude extract against H. armigera (70.3%) and S. litura (71.82%) at 1% concentration. Ethyl acetate crude extract was further subjected to column chromatography, which was performed
using hexane as initial solvent and then by increasing the polar strength using ethyl acetate. Fractions collected at hexane
and ethyl acetate (80:20) yielded 6-(4,7-hydroxy-heptyl) quinone, a novel compound which showed significant antifeedant activity
against H. armigera (80.22% at 2000 ppm) and S. litura (68.31% at 2000 ppm). 相似文献
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Combined effects of beta-glucan and lipopolysaccharide (LPS) on survival and immune response were studied in Cyprinus carpio that were challenged with the pathogen Aeromonas hydrophila. beta-Glucan from Saccharomyces cervisiae and LPS from a virulent strain of A. hydrophila were used in this study. Different concentrations of beta-glucan+LPS mixture were administered on days 1, 7, and 14 through different routes (intraperitoneal injection, bathing, and oral administration). Control and test fish were challenged by intraperitoneal injection of LD50 concentration of A. hydrophila on day 16 and subsequently, mortality and relative percent survival (RPS) were recorded. Intraperitoneal injection elicited 100% RPS even at the lowest concentration (100 microg beta-glucan+10 microg LPS); whereas, oral administration improved RPS rate of carps at higher concentration (1% beta-glucan+0.25% LPS). Bathing did not improve the RPS. Test animals injected with even the minimum dose of the immunomodulators (100 microg beta-glucan+10 microg LPS/fish) had a significant increase in total blood leukocyte counts and an increase in the proportion of neutrophils and monocytes. Superoxide anion production by macrophages was also elevated, which presumably aided the efficient killing of bacterial pathogen. Lower concentration of beta-glucan+LPS had an adjuvant effect on antibody production as pretreatment by injection of 100 microg beta-glucan+10 microg LPS/fish resulted in higher antibody titer against A. hydrophila following vaccination. RT-PCR analyses showed that the expression of interleukin-1beta mRNA did not increase in test fish when compared with the control. Classical and alternative complement pathways were not affected by either the dose or the route of administration of the compounds. It may be concluded that intraperitoneal injection and oral administration, and not the bathing, of beta-glucan+LPS mixture in carp could enhance resistance to challenge by A. hydrophila through changes in several non-specific and specific immune responses. 相似文献
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In chickens, thymic CD4(+)CD25(+) cells are characterized as regulatory T cells. The objectives of this experiment were to study the effects of an in vivo lipopolysaccharide (LPS) injection on the percentage of CD4(+)CD25(+) cells in peripheral organs and the suppressive properties of splenic CD4(+)CD25(+) cells in chickens. Chickens were injected with LPS and CD4(+)CD25(+) cells were analyzed at 1, 2, 3, 5, and 10 d post LPS injection. The LPS injection increased CD4(+)CD25(+) cell percentage approximately 5-fold in the blood at 1 d post LPS injection (P < 0.001), 3-fold in the thymus at 3 d post LPS injection (P = 0.001), and 2.5-fold in the spleen at 2 d post LPS injection (P = 0.001) compared with the no-LPS-injected group. The LPS injection did not alter the CD4(+)CD25(+) cell percentage in the cecal tonsil (P = 0.162), lung (P = 0.098), or bone marrow (P = 0.071) at any time point measured. At 2 d post LPS injection, splenic CD4(+)CD25(+) cells lost their suppressive ability (P < 0.001). At 5 d post LPS injection, splenic CD4(+)CD25(+) cells not only regained their suppressive ability, but also became supersuppressive (P < 0.001). Splenic CD4(+)CD25(+) cells at 5 d post LPS injection produced 5.5-fold more (P = 0.005) IL-10 mRNA than splenic CD4(+)CD25(+) cells at 0 and 2 d post LPS injection. In conclusion, chicken regulatory T cells are differentially activated to facilitate immune response during the early stage of inflammation and to facilitate immune suppression at a later stage of inflammation. 相似文献
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Venkataramanan Ragothaman Sreekumar Chirukandoth Anilkumar Rishipal Selvaraj P. Vidhya Nainar M. Mathagowder Iyue 《Tropical animal health and production》2010,42(5):1027-1029
Silage, which is anaerobically fermented green fodder, is valued throughout the world as a source of animal feed during lean
months. Several farms in India use carbohydrate sources like jaggery or molasses at 2% for preparation of silage, and this
increases cost of production. The present study was undertaken to assess the effect of jaggery on quality and intake of maize
silage, with an objective to find out whether additional carbohydrate source is essential in preparation of silage using green
maize. Three silage types, one without jaggery (A), the second with 1% jaggery (B), and the third with 2% jaggery (C) were
prepared in cylindrical bins under similar conditions. They were compared for colour, pH, lactic acid bacteria count, lactic
acid content, proximate composition and silage intake by sheep. Silage type C with 2% jaggery was significantly different
from the other two types with values of 3.98 and 805.66 g for pH and mean silage intake, respectively. Even though the values
of pH and dry matter intake for all three silage types were within normal levels, silage type C was significantly superior
in terms of fermentation and palatability. The method of preparation followed could be ideal for small holder farmers requiring
less quantity of silage. 相似文献
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R. Venkataramanan C. Sreekumar S. Krishnakumar R. Anil Kumar J. Selvaraj 《Equine Veterinary Education》2018,30(7):356-359
This case report describes a rare case of vaginal myxoma in a Kathiawari mare. The tumour, located on the left lateral vaginal wall, measured approximately 20 cm in diameter and resulted in dysuria, inappetance and loss of condition of the animal. Surgical enucleation of the tumour via a vaginal approach resulted in uneventful recovery of the horse. Based on the gross and histopathological observations, the tumour was diagnosed as a myxoma. 相似文献
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Experiments were carried out to possibly reduce bait shyness of female house rats by masking the poison (rodenticide-Zn3P2) with male pheromonal gland secretions, i.e. preputial/cheek glands and urine. The poison bait mixed with the extract of preputial and cheek glands, and urine was found to be effective in masking poison bait shyness. Preputial and cheek gland extracts cumulatively mixed with poison bait increased the poison bait consumption and consequently the mortality of female rats. The results reveal that among three pheromone sources, preputial gland extract was the most effective followed by urine and cheek gland extract. The results further reveal that the urine and glandular secretion from male origin may have the ability to increase the poison bait acceptance in female rats probably by altering the taste memory by pheromone odours. 相似文献
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N. Selvaraj A. Vasudevan M. Manickavasagam S. Kasthurirengan A. Ganapathi 《Scientia Horticulturae》2007
Organogenic callus induction and high frequency shoot regeneration were achieved from cotyledon explants of cucumber. About 86.2% of cotyledon explants derived from 5-day-old in vitro raised seedlings produced green, compact nodular organogenic callus in MS medium containing NAA (2.69 μM) and BA (4.44 μM) after two successive transfers at 20 days interval. Adventitious shoots were produced from the organogenic callus when it was transferred to MS medium supplemented with NAA (1.34 μM), BA (8.88 μM), zeatin (0.91 μM) and l-glutamine (136.85 μM) with shoot induction frequency of 75.6%. Shoot proliferation occurred when callus with emerging shoots was transferred in the same medium at an interval of 20 days. Shoots (1.0 cm length) were excised from callus and were elongated in MS medium fortified with GA3 (1.44 μM) and BA (4.44 μM). The elongated shoots were rooted in MS medium supplemented with IBA (3.42 μM) and BA (4.44 μM). Rooted plants were acclimatized in green-house and subsequently established in soil with a survival rate of 80%. This protocol yielded an average of 35 shoots per cotyledon explant in a culture duration of 120–140 days. 相似文献
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M L Hibbs P Selvaraj O Carpén T A Springer H Kuster M H Jouvin J P Kinet 《Science (New York, N.Y.)》1989,246(4937):1608-1611
Granulocyte and natural killer (NK) cell Fc receptors for immunoglobulin G (CD16) differ in only a few amino acids, yet have phosphatidylinositol glycan (PIG) or polypeptide membrane anchors, respectively. Mutagenesis shows that anchoring is regulated by a serine residue near the PIG anchor attachment site in the extracellular domain. The NK cell isoform was not expressed on the surface of COS cells unless cotransfected with a subunit that was expressed in NK cells and that was identical to the gamma subunit of the high affinity IgE Fc receptor (Fc epsilon RI). However, the CD16 sequence and not expression of the gamma subunit is dominant in regulating PIG reanchoring. 相似文献
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Serum‐based biomarkers hold propitious applications for addressing livestock health, and management. However, discovery of protein biomarkers in complex biological fluids like serum is wholly intractable due to the large dynamic range of protein concentrations; that is, ?10–12 high abundance proteins constitute >90% of the total protein content and effectively mask proteomic detection of low‐abundance biomarkers. Toward addressing this limitation, we test a continuous elution size‐based fractionation method, and two approaches that use affinity interaction‐based separation of proteins in preparing bovine serum, and compare liquid chromatography tandem mass spectrometry protein identification to neat serum. Our results identify the high‐abundance proteins in bovine serum, and demonstrate dynamic range compression and improved protein identification with the different enrichment methods. Although these findings indicate the highest protein number identified in bovine serum (445 proteins, all methods combined), and by any single sample processing method (312 proteins) to date, they still remain lower than levels deemed necessary for biomarker discovery. As such, this investigation revealed limitations to resolving the bovine serum proteome, and the need for species‐specific tools for immunodepleting high‐abundance proteins. In concert, this study represents a step toward advancing sample preparation methods for bovine serum biomarker identification. 相似文献