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81.
82.
The therapeutic efficacy of imidocarb, artesunate, arteether, buparvaquone and arteether+buparvaquone combination was evaluated against Babesia equi of Indian origin in splenectomised donkeys with experimentally induced acute infection. Efficacies of these drugs were tested by administering each drug or drug combination to groups of donkeys (having three donkeys each group). One group of donkey was kept as untreated control for comparing the results. Parasitaemia, haematology (WBC, RBC, PCV, granulocytes and haemoglobin), biochemical parameters (SAST, SALT, alkaline phosphatase, albumin/globulin ratio) were monitored at regular intervals. Individually, arteether and buparvaquone were found to have no parasite clearing efficacy and the treated animals died within 5-6 days after showing high parasitaemia and clinical symptoms of the disease. However, artesunate treated animals were able to restrict the parasite multiplication but only during the treatment period. Animals treated with imidocarb and arteether+buparvaquone combination were able to clear the parasite from the blood circulation after 2-5 days post-treatment (PT). After 55-58 days PT, recrudescence of B. equi parasite was observed in both these groups and a mean survival period of 66 days and 69 days, respectively, was recorded in these groups. Results of haemato-biochemical parameters had shown that imidocarb had deleterious effect on the liver function while on the other hand arteether+buparvaquone combination was found to be safe. This limited study indicates that arteether+buparvaquone combination could be a better choice than imidocarb for treating B. equi infection, but further trials are required in detail.  相似文献   
83.
Described are the first antemortem diagnosis made via fecal examination using the Baermann technique and the first postmortem recovery of endemic Angiostrongylus vasorum in dogs from North America, specifically the Avalon peninsula of Newfoundland. In one dog, A. vasorum was recovered and identified at postmortem; gross and histologic lesions are described.  相似文献   
84.
The influence of position of cuttings, auxin treatments and seasonal variation on adventitious rooting of Dendrocalamus asper, a multipurpose edible bamboo of horticultural value, was examined. Single node proximal (culm) and distal (culm-branch) cuttings were collected during the months of April–June and treated for 24 h with water or 2 mM auxin (indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and naphthalene acetic acid (NAA)). The treated cuttings were planted horizontally in sand beds and maintained under misting conditions for 2 months. Culm cuttings exhibited better adventitious rooting than culm-branch cuttings and the month of May proved to be the best for rooting of both types of cuttings. Auxin treatments also influenced adventitious rooting and their effectiveness was in the order: NAA>IBA>IAA. The interaction among auxin, position of cuttings and month of collection was also found to be significant on root induction and differentiation. Single node culm cuttings, without auxin treatment, resulted in 98% plantlets in May and 67% plantlets in June, and emerged as a suitable material for large-scale vegetative propagation. Administration of IAA or NAA to abundant culm-branch cuttings of low commercial utility (collected in May) also produces ≥50% plantlets.  相似文献   
85.
Brassica campestris was infected with the angiosperm parasite,Cuscuta reflexa, on 24 DAS (days after sowing). A significant reduction (43%) in carbon dioxide assimilation in leaves was found compared to normal plant, when both were assayed on 38 DAS. At this stage, the chloroplast lipid in infected leaves had decreased by 34%, with a reduction of 13, 38 and 55%, respectively, in neutral, glyco- and phospholipids. Among the glycolipids, the decrease in the content of MGDG, DGDG and SQDG was 21, 67 and 44%, respectively, with 2.4-fold increase in the MGDG/DGDG ratio. The chlorophyll content was reduced by 24%, while the carotenoid level increased by 44%. The free fatty acid content was enhanced by 47% which may be attributed to an increase in lipase activity. The contents of saturated fatty acids (capric, lauric, myristic, palmitic and stearic) increased while the contents of unsaturated fatty acids (palmitoleic, oleic, linoleic and linolenic) decreased. The ratio of unsaturated to saturated fatty acids decreased over 50%. These findings may suggest chloroplasts as reactive sites of the host-parasite interaction in case of the angiosperm parasite.Abbreviations DAS day after sowing - DGDG digalactosyl diglyceride - FAME fatty acid methyl esters - FFA free fatty acids - MGDG monogalactosyl diglyceride - SQDG sulfoquinovosyl diglyceride  相似文献   
86.
Crataeva magna (Lour.) DC (synonym C. nurvala) is a high-value Indian medicinal tree. The multiple uses of C. magna have resulted in its over-exploitation. Erratic seed germination combined with destructive harvesting and habitat destruction in the form of deforestation has added to the enormity of the problem. Therefore, the need for conservation of this plant is vital. Development of an efficient micropropagation protocol will play a significant role in meeting the requirement of quality planting material for commercial cultivation thereby conserving the species in its natural habitat. In the present study, shoot multiplication was achieved by culturing single node segments derived from a field grown tree on Murashige and Skoog’s (MS) medium supplemented with 2.66 μM N6-benzyladenine, 1.39 μM Kinetin (Kn), 0.57 μM indole-3-acetic acid (IAA), 3% sucrose and 0.2% gelrite. 96% rooting was achieved within 22 days by culturing the in vitro formed shoots on half strength MS medium with 11.42 μM IAA, 9.8 μM indole-3-butyric acid, 0.46 μM Kn and 198.25 μM phloroglucinol. Following a simple hardening procedure involving sequential transfer of plants to a greenhouse, polyhouse, and shade net, the tissue-cultured plants were transferred to the field where the survival rate was 100%. To this date 500 plants have been produced. Inter simple sequence repeat analysis has confirmed genetic uniformity of the tissue-cultured plants.  相似文献   
87.
88.
The study was conducted to improve our understanding of the effects of forest disturbance on litterfall and patterns of nutrient return in three subalpine forest ecosystems (i.e. Betula utilis-dominated, Abies pindrow-dominated, and Acer mixed broadleaf) of Indian west Himalaya. Total litterfall (t ha−1 yr−1) ranged between 2.6–3.6 and 2.1–2.6 for pristine and degraded stands, respectively. Whereas total litterfall decrease from pristine to degraded stand was about 25–30% in B. utilis and Acer mixed-broadleaf forests, the level of disturbance did not affect total litterfall in A. pindrow (coniferous) forest. Nutrient (N, P, and K) concentrations in litter components of the forests studied also varied across forest types and disturbance intensities. For pristine stands, among all the forests, return of total nutrients via litterfall was higher. The study revealed that patterns of litterfall and nutrient return in the forests studied were sensitive to intensity of disturbance, although sensitivity varied among forest types and nutrient contents. Increased intensity of disturbance greatly affected the total annual amount of nutrient return in broadleaf forests. Maximum impact was recorded in B. utilis forest with a significant decline in nutrient return from pristine to degraded stands (i.e. 64% for N, 38% for P, and 67% for K). Corresponding values for decline in Acer mixed forest were 17, 13, and 33% for N, P, and K, respectively, whereas in A. Pindrow forest N return was 15% higher and P return was 33% lower. This study indicates that the litterfall and litter nutrient concentrations in these forests are sensitive to the intensity of disturbance, which affects the amount of nutrient return. This will have a strong bearing on forest nutrient cycling.  相似文献   
89.
Water, Air, &; Soil Pollution - High applications of P fertilizers and manure are general practice in intensive agriculture and may cause eutrophication in adjacent streams. Bioavailability of P...  相似文献   
90.
An attempt was made to assess the effect of dietary pyridoxine supplementation on growth performance and cellular metabolic enzymes of Chanos chanos fingerlings under endosulfan induced stress. Two‐hundred and twenty‐five fish were randomly distributed into five treatments, each with three replicates and fed four isocaloric and isonitrogenous diets with graded levels of pyridoxine for 45 days. Endosulfan concentration in the water was maintained at sublethal level of 1/40th of 96 h LC50 (0.52 ppb). Dietary pyridoxine supplementation significantly enhanced growth performance viz. weight gain (%), specific growth rate, feed conversion ratio and protein efficiency ratio of fish compared to control diet fed group. The results of this experiment revealed that the activities of digestive and metabolic enzymes were significantly improved after feeding with dietary pyridoxine supplementation in C. chanos. Significantly increased muscle and brain ascorbic acid content was observed in fish fed diets containing pyridoxine. Histological studies on liver of fish fed pyridoxine‐supplemented diet showed the normal architecture of hepatocytes compared to non‐pyridoxine fed group. The results obtained in this study revealed that the inclusion of pyridoxine in diet has a protective effect against endosulfan induced stress in C. chanos fingerlings through metabolic enzyme activities and vitamin C content. This study has a potential in ameliorating the toxic effect of endosulfan induced stress using dietary supplementation of pyridoxine.  相似文献   
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