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41.
T. Das N. P. Sahu S. K. Chakraborty N. Chatterjee M. S. Mohammed R. S. Dalvi K. Baruah A. K. Pal 《Anatomia, histologia, embryologia》2014,43(1):75-80
This study aimed to determine the cellular alterations in the gill of Labeo rohita exposed to lethal temperature maxima (LTMax) and lethal temperature minima (LTMin) by means of transmission electron microscopy (TEM). Acclimation of advanced fingerlings of L. rohita was carried out at 26°C for 30 days. Acclimated fish were subjected to a constant rate of increase or decrease in temperature (0.3°C/min) until the LTMax and LTMin values were reached. Dissected gills were processed for TEM, both at the end of acclimation period at ambient temperature (26°C) and at lethal temperatures. Results indicated that at ambient temperature, the gill tissues appeared normal. However, significant changes were observed at lethal temperatures. The gill tissues at lethal temperature maxima showed severely damaged lamellae, with more vacuolated space. At lethal temperature minima, gill tissues showed increased density of mitochondria. Our prima‐facie report indicated that L. rohita exposed to lethal temperatures exhibited marked ultrastructural changes in the gills. 相似文献
42.
Kartik Baruah Narottam P. Sahu Asim K. Pal Dipesh Debnath Sona Yengkokpam Subhas C. Mukherjee 《Journal of the World Aquaculture Society》2007,38(2):238-249
A 2 × 2 × 2 factorial experiment was designed to study the effect of microbial phytase (MP), citric acid (CA), and crude protein (CP) and their interactions on mineral utilization by rohu, Labeo rohita, juveniles. Two basal diets containing 25% (subnormal) or 35% (normal) CP were supplemented with MP (units, U/kg) and CA (%) at 0, 0; 500, 0; 0, 3; and 500, 3, respectively and fed to 125 juveniles (average initial weight: 13.16 g/fish). MP did not affect fecal ash content but CA (3%) addition activated MP. Apparent absorption of Zn, its content in whole body and plasma, was significantly (P < 0.05) higher in CA‐ and MP‐fed groups. Interaction between CA and MP was found for increased absorption of Na, P, K, Mn, Mg, Fe, and N, their concentrations in whole body and plasma. Cu and Ca absorption, and their concentration in body and plasma were increased as a result of addition of CA, MP, or their interaction. Thus, bioavailability of major minerals was highest in groups fed diets containing 500‐U MP and 3% CA. This improvement was more prominent in subnormal CP diet. Growth performance was also highest in this group. Thus, CA and MP at 25% CP diet had synergistic effect on mineral bioavailability in L. rohita. 相似文献
43.
Every organism responds to heat stress by synthesizing a group of evolutionarily conserved proteins called the heat-shock proteins (HSPs) that, by acting as molecular chaperones, protect the cell against the aggregation of denatured proteins and play a significant role in adaptation to temperature. The present study aimed to investigate the critical thermal maxima (CTMax) and the expression of HSP70 in different tissues (gill, brain, muscle and liver) of an endemic catfish Horabagrus brachysoma acclimated at either 20 or 30°C for 30?days. To understand the HSP70 response, fish acclimated to the two temperatures were exposed to preset temperatures (26, 30, 34, 36 and 38°C for 20°C acclimated fish and 32, 34, 36, 38 and 40°C for 30°C acclimated fish) for 2?h, followed by 1?h recovery at their respective acclimation temperatures. The HSP70 levels in the gill, brain, muscle and liver tissues were determined by Western blotting of one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis. A significant (P?相似文献
44.
Shivendra Kumar N. P. Sahu A. K. Pal Vidya Sagar Amit Kumar Sinha Kartik Baruah 《Fish physiology and biochemistry》2009,35(2):301-315
A 60-day feeding trial was conducted to delineate the effect of both gelatinized (G) and non-gelatinized (NG) corn with or
without supplementation of exogenous α-amylase, either at optimum (35%) or sub-optimum (27%) protein levels, on blood glucose,
and the key metabolic enzymes of glycolysis (hexokinase, HK), gluconeogenesis (glucose-6 phosphatase, G6Pase and fructose-1,6
bisphosphatase, FBPase), lipogenesis (glucose-6 phaosphate dehydrogenase, G6PD) and amino acid metabolism (alanine amino transfersae,
ALT and aspartate amino transferase, AST) in Labeo rohita. Three hundred and sixty juveniles (average weight 10 ± 0.15 g) were randomly distributed into 12 treatment groups with each
of two replicates. Twelve semi-purified diets containing either 35 or 27% crude protein were prepared by including G or NG
corn as carbohydrate source with different levels of microbial α-amylase (0, 50, 100 and 150 mg kg−1). The G corn fed groups showed significantly higher (P < 0.05) blood glucose and G6PD activity, whereas G6Pase, FBPase, ALT and AST activity in liver was higher in the NG corn fed
group. Dietary corn type, α-amylase level in diet or their interaction had no significant effect (P > 0.05) on liver HK activity, but the optimum crude protein (35%) fed group showed higher HK activity than their low protein
counterparts. The sub-optimum crude protein (27%) fed group showed significantly higher (P < 0.05) G6PD activity than the optimum protein fed group, whereas the reverse trend was observed for HK, G6Pase, FBPase,
ALT and AST activity. Addition of 50 mg α-amylase kg−1 feed showed increased blood glucose and G6PD activity of the NG corn fed group, whereas the reverse trend was found for G6Pase,
FBPase, ALT and AST activity in liver, which was similar to that of the G or NG corn supplemented with 100/150 mg α-amylase
kg−1 feed. Data on enzyme activities suggest that NG corn in the diet significantly induced more gluconeogenic and amino acid
metabolic enzyme activity, whereas G corn induced increased lipogenic enzyme activity. Increased amino acid catabolic enzyme
(ALT and AST) activity was observed either at optimum protein (35%) irrespective of corn type or NG corn without supplementation
of α-amylase irrespective of protein level in the diet. 相似文献
45.
R. Bhatta L. Baruah M. Saravanan K. P. Suresh K. T. Sampath 《Journal of animal physiology and animal nutrition》2013,97(3):446-456
The potential of tannins from 21 medicinal and aromatic plant leaves as antimethanogenic additives in ruminant feeds was investigated. The effect of tannin from these leaves on rumen fermentation parameters, protozoa population and methanogenesis was studied by incubating the samples [200 mg dry matter (DM)] without and with polyethylene glycol (PEG)‐6000 (400 mg DM) as a tannin binder during 24‐h incubation in the in vitro Hohenheim gas method. Based on the methane percentage estimated in the total gas produced, methane production in millilitre was calculated [methane volume (ml) = methane % × total gas produced (ml) in 24 h]. In the samples, crude protein and neutral detergent fibre (g/kg DM) ranged from 113 to 172 and from 352 to 444 respectively. The total phenol (TP; g/kg DM) content was highest in Terminalia chebula (274) followed by Hemigraphis colorata (71) and Sapindus laurifolia (51) respectively. In the remaining samples, it was <43 g/kg DM. Activity of tannins, as represented by the increase in gas volume on addition of PEG, ranged from 0 to 133%, with the highest being recorded in T. chebula. The per cent increase in methane on PEG addition was 0 for Ammi majus, Aristolochia indica, Cascabela thevetia, Ipomea nil and Lantana camara, illustrating that tannins present in these samples had no effect on methane concentration. The PEG addition increased the total protozoa count by >50% in A. indica and C. thevetica. One of the important findings of our study was that of the 21 samples screened, Entodinia population increased in 12 with PEG as compared to 7 where Holotricha increased, indicating higher susceptibility of Entodinia to tannin. There was no increase in the protozoa population with PEG when incubating Cardiospermum halicacabum, Clerodendrum inerme, Dioscorea floribunda, Nerium oleander and Selastras paniculatus, which strongly suggested that methane suppression recorded in these samples was not because of a defaunating effect of their tannins per se. The fermentation pattern reflected increased total volatile fatty acid (TVFA) concentration from 0 to 28.3% with PEG addition among the leaves. Our results confirmed further observations that methanogenesis in vitro is not essentially related to density of protozoa population. Secondly, medicinal and aromatic plants such as C. inerme, Gymnema sylvestre and Sapindus laurifolia containing tannins appear to have a potential to suppress in vitro methanogenesis. 相似文献
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47.
Characterization of phenotype variations of luminescent and non‐luminescent variants of Vibrio harveyi wild type and quorum sensing mutants 
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下载免费PDF全文 Vibrio harveyi, a luminescent Gram‐negative motile marine bacterium, is an important pathogen responsible for causing severe diseases in shrimp, finfish and molluscs leading to severe economic losses. Non‐luminescent V. harveyi obtained by culturing luminescent strains under static and dark condition were reported to alter the levels of virulence factors and metalloprotease gene and luxR expression when compared to their luminescent variants. Presently, we conducted an in vitro study aiming at the characterization of virulence‐related phenotypic traits of the wild‐type V. harveyi BB120 strain and its isogenic quorum sensing mutants before and after switching to the non‐luminescent status. We measured the production of caseinase, haemolysin and elastase and examined swimming motility and biofilm formation. Our results showed that switching from the bioluminescent to the non‐luminescent state changed the phenotypic physiology or behaviour of V. harveyi resulting in alterations in caseinase and haemolytic activities, swimming motility and biofilm formation. The switching capacity was to a large extent independent from the quorum sensing status, in that quorum sensing mutants were equally capable of making the phenotypic switch. 相似文献
48.
Mohamed Omar El-Magsodi Kartik Baruah Parisa Norouzitallab Peter Bossier Patrick Sorgeloos Gilbert Van Stappen 《Aquaculture International》2016,24(2):429-439
The brine shrimp Artemia franciscana is an important live feed for fish and shellfish larviculture. Cysts of Artemia are naturally found in a wide variety of harsh environments worldwide where they are exposed to different changing environmental conditions. Artemia cysts are also exposed to different hydration/dehydration (H/D) conditions during the post-harvest processing period in the Artemia processing industry. In this study, cysts of two strains of A. franciscana originating from two different geographical locations—one a natural population from Great Salt Lake (GSL), Utah, USA, and the other cultured in the Vinh Chau (VC) salt ponds, Vietnam—where they experience different environmental factors, were exposed to successive hydration/dehydration (H/D) cycles with the aim of determining the effects of these conditions on the stress (i.e., induction of Hsp70) and functional (i.e., resistance toward abiotic and pathogenic biotic factors) responses of the emerged nauplii. Our results showed that a short period of H/D of the cysts did not appear to have a deleterious effect on the emerged nauplii of both strains, as was evidenced by the absence of significant difference in the survival of nauplii emerged from the control and treated cysts, upon challenge with a thermal stressor or with pathogenic Vibrio campbellii. A limited exposure to H/D treatment even leads to the induction of enhanced thermotolerance in GSL nauplii. In essence, these observations add some insights to our current understanding of stress responses in Artemia under the described experimental conditions. In addition, the impact of H/D cycles associated with stress response should be taken into consideration when Artemia is considered as a model organism for future research and applications. 相似文献
49.
Anushree Baruah Dipti Gorh Prabhat Kumar Gupta 《Communications in Soil Science and Plant Analysis》2016,47(11):1417-1429
Experiments were conducted in an attempt to study the impact of using different organic residues as fertilizers on grain yield, magnitude of nitrous oxide (N2O) emissions, and soil characteristics. Five fertilizer treatments including conventional nitrogen (N) fertilizer, cow manure, rice straw, poultry manure, and sugarcane bagasse were applied in the rice field in 2012. The maximum reduction in seasonal N2O emissions (10–27%) was observed under the influence of rice straw application over conventional N fertilizer. The experiment was repeated for a second season in 2013 with the same treatments for further confirmation of the results obtained during the first year of experimentation. The application of rice straw also showed a slight advantage by increasing grain yield (4.38 t ha?1) compared to control. Important soil properties and plant growth parameters were studied and their relationships with N2O emission were worked out. The incorporation of organic residues helped in restoring and improving the soil health and effectively enhancing grain yield with reduced N2O emission from rice fields. 相似文献
50.
An assessment of the olive ridley turtle (Lepidochelys olivacea) nesting population in Orissa, India
Olive ridley mass nesting events or ‘arribadas’ have been documented in Orissa, India since 1974. However, since standardised techniques have not been used to census turtles, actual population trends remain unknown. Herein, we summarise information on nesting populations in Orissa, using data from multiple sources to arrive at consensus estimates and to derive trends. We conducted a quantitative estimate of an arribada in March 1999, where nesting was estimated as ∼180,000 turtles by the strip transect method. Non-linear (quadratic) fits for arribada data from 1976-1999 and a recent decrease in the size of adults suggest a potential or imminent decline, consistent with fishery-related mortality of at least 90,000 turtles since 1994. Though statistical support for the recent decline is equivocal, efforts to reduce mortality and close monitoring of the population would be prudent. The absence of reliable data on which to base conservation action highlights an urgent need to train management personnel in data collection and estimation techniques for effective monitoring of status, threats and trends. 相似文献