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31.
Juan B Barron LJ Ferragut V Guamis B Trujillo AJ 《Journal of agricultural and food chemistry》2007,55(3):747-754
The effect of high-pressure (HP) treatment (300 MPa, 10 min) on the volatile profile of semihard ewe milk cheeses was investigated. The HP treatment was applied at two different stages of ripening (1 and 15 days; 3P1 and 3P15) and microbiota, proteolysis indexes (soluble nitrogen and total free amino acid content), and volatile compounds were assayed at 15, 60, 90, and 150 days of ripening. The intensity of odor and aroma of cheeses was also assayed. 3P1 cheeses presented the highest content of free amino acids and were characterized by the lowest amounts of aldehydes, ketones, short-chain free fatty acids, and terpenes and higher levels of ethanol and ethyl esters. 3P15 cheeses were characterized by the highest content of short-chain free fatty acids and pyruvaldehyde and the lowest abundance of secondary alcohols and were more similar to control cheeses than those HP-treated on the first day. Intensities of odor and aroma were not significantly influenced by the HP treatment. However, the panellists found some differences in 3P1 as compared with control and 3P15 cheeses in what they perceived as lower odor and aroma quality. 相似文献
32.
Cant-Tejero Manuel Casas Jos Luis Marcos-Garca Mara ngeles Pascual-Villalobos Mara Jess Florencio-Ortiz Victoria Guirao Pedro 《Journal of pest science》2022,95(1):365-379
Journal of Pest Science - Aphids are one of the major agricultural pests in the world. Their pest management in pepper greenhouses is based on integrated control with release of natural enemies and... 相似文献
33.
Thomas A. Heming David J. Randall Madeleine M. Mazeaud 《Fish physiology and biochemistry》1987,3(2):83-90
Effects of adrenaline on the equilibrium distributions of Na+ , K+ , H+ , Cl– , and H2O across the cell membrane of rainbow trout (Salmo gairdneri) erythrocytes were determinedin vitro, as a function of P CO2 (1.76–7.77 torr). CO2-carrying capacity of the blood was also examined. Plasma catecholamine concentrations inunanaesthetized, unrestrained trout were 3.1 nM adrenaline and 1.2 nM noradrenaline. Elevation of the plasma adrenaline concentrationin vitro to 4.6 × 103 nM resulted in net gains of Na+ , Cl– and H2O by red cells, a net loss of H+ from red cells, and a pronounced red cell swelling. Adrenaline also reduced the CO2-carrying capacity of trout bloodin vitro. The magnitudes of these effects increased with PCO2 and, thus, were sensitive to blood HCO3
– concentrations. The distribution of K+ between red cells and plasma was unaffected by adrenaline. Adrenergic-mediated ion movements and red cell swelling were sensitive to both propranolol and SITS. These results are consistent with the symport NaCl uptake model for adrenergic-mediated swelling of Baroinet al. (1984). The adrenergic response of fish erythrocytes may function to ameliorate the effects of blood acidoses on O2-carrying capacity by maintaining red cell pH in the face of a decrease in plasma pH. 相似文献
34.
35.
B.S. Dosanjh D.A. Higgs D.A. Higgs D.J. McKenzie D.J. Randall J.G. Eales N. Rowshandeli M. Rowshandeli G. Deacon 《Fish physiology and biochemistry》1998,19(2):123-134
The effects of various dietary blends of menhaden oil (MO) with canola oil (CO) on the growth performance, whole body proximate composition, flesh quality (muscle proximate and lipid composition) and thyroidal status of immature Atlantic salmon in sea water were studied.Atlantic salmon (initial weight, 145.2–181.3 g), held on a natural photoperiod and in 1100 L fibreglass tanks that were supplied with running, aerated (D.O., 9–10.5 p.p.m.), ambient temperature (8–10.5 °C) sea water (salinity, 28–30), were fed twice daily to satiation one of four isonitrogenous (36% digestible protein) and isoenergetic (18.8 MJ of digestible energy kg-1) extruded high-energy diets for 112 days. All diets contained omega –3 (n-3) fatty acids in excess of requirements and differed only with respect to the source of the supplemental lipid which was either, 25% MO; 20.75% MO and 4.25% CO; 16.5% MO and 8.5% CO; or 12.25% MO and 12.75% CO. Thus, CO comprised, respectively, 0, 15.5, 31.2, or 47.0% of the total dietary lipid content (28% on an air-dry basis).Dissimilar percentages of saturated fatty acids in the dietary lipids were not found to be consistently related to the apparent gross energy digestibility coefficients of the diets. Atlantic salmon growth, dry feed intake, feed and protein utilization, percent survival, thyroidal status, and whole body and muscle proximate compositions were generally not influenced by the different sources of supplemental lipid. Therefore, our results suggest that canola oil may comprise as much as 47% of the lipid in high-energy grower diets for Atlantic salmon without compromising performance.The muscle lipid compositions generally mirrored those of the dietary lipids which, in turn, were influenced strongly by the concentrations and compositions of the CO and MO in the diet. Hence, as the dietary CO level was increased there were attendant increases in percentages of oleic acid (18:1(n-9)), linoleic acid (18:2(n-6)), total omega-6 (n-6) fatty acid content, and ratios of (n-6) to (n-3) and decreases of eicosapentaenoic acid (EPA; 20:5(n-3)), docosahexaenoic acid (DHA; 22:6(n-3)) and n-3 HUFAs (EPA & DHA) in the flesh lipids. The ranges for percentages of saturated and unsaturated fatty acids in the flesh lipids were, however, much less than those noted respectively in the dietary lipids probably because of selective metabolism of many of the former acids and some of the 18 carbon unsaturates for energy purposes. 相似文献
36.
37.
We investigated ventillatory responses to a plasma alkaloids and hypocapnia,a nd the basis for the ventilatory response to sodium bicarbonate (NaHCO3) infusion in rainbow trout. Plasma alkalosis and hypocapnia created by infusion of sodium hydroxide (NaOH) did not cause hypoventilation, whereas infusion of hydrochloric acid (HCl) caused vigorous hyperventilation, associated with an acidosis, a reduction in blood O2 content (CaO
2) and a release of circulating catecholamines. Infusion of NaHCO3 stimulated ventilation and caused an increase in plasma pH, total carbon dioxide content (CaCO
2) and catecholamine levels, and a reduction in oxygen tension (PaO
2). Infusion of ammonium bicarbonate (NH 4HCO3) caused hyperventilation and was associated with an increase in CaCO
2 and plasma total ammonia (Camm) and ammonia gas (NH3) concentration. Infusion of sodium chloride (NaClI) and Cortland's saline had no effect on ventilation. The results indicate that trout do not exhibit the ventilatory sensitivity to pH seen in terrestrial vertebrates. Ventilatory responses to NaHCO3 appear to have been a result of reductions in PaO
2, a release of catecholamines and an increase in CaCO
2 whereas responses to NH4HCO3 appear to have been a result of increases in CaCO
2 and Camm. 相似文献
38.
Chronically cannulated rainbow trout were exposed in acid water (pH 4.0) for 72h. The gill potential was strongly dependent on water pH, being blood side negative in neutral water, but positive in acid water. Catecholamine levels increased irregularly during acid exposure, and the Bohr and Root effects were not completely erased by the effect of catecholamines during acid exposure. Long term exposure to low water pH, although causing an acidosis in the fish, did not suppress resting oxygen consumption. Prolonged exposure to acid conditions, however, resulted in an increase in ammonia excretion. Changes in plasma sodium and chloride were similar to that reported previously for trout exposed to low calcium, acid water. We conclude that exposure of trout to pH 4 soft water, although impairing oxygen transport, does not limit resting oxygen consumption but does reduce the scope for activity. More extreme acid conditions do impair resting oxygen uptake. 相似文献
39.
Ammonia distribution and excretion in fish 总被引:6,自引:0,他引:6
This paper reviews the literature concerning ammonia production, storage and excretion in fish. Ammonia is the end product of protein catabolism and is stored in the body of fish in high concentrations relative to basal excretion rates. Ammonia, if allowed to accumulate, is toxic and is converted to less toxic compounds or excreted. Like other weak acids and bases, ammonia is distributed between tissue compartments in relation to transmembrane pH gradients. NH3 is generally equilibrated between compartments but NH4
+ is distributed according to pH. Ammonia is eliminated from the blood upon passage through the gills. The mechanisms of branchial ammonia excretion vary between different species of fish and different environments, and primarily involves NH3 passive diffusion and NH4
+/Na+ exchange. Water chemistry near the gill surface may also be important to ammonia excretion, but a more accurate measurement of the NH3 gradient across the gill epithelium is required before a more detailed analysis of NH3 and NH4
+ excretion can be made. 相似文献
40.
The role of learning in fish orientation 总被引:6,自引:0,他引:6
Past research on fish orientation and migration has tended to focus on genetically fixed patterns of behaviour. However, in most aquatic environments, the physical landscape as well as biologically important locations will be subject to varying degrees of change, favouring an ability to learn. Here, we review the evidence from field and laboratory‐based experiments that fish can and do use learning and memory to orientate within their natural environments, relying on information from a diverse array of different sources. Comparisons of different species and populations suggest that fish may be predisposed to learn specific associations at specific times or places, appropriate for the particular navigational problems that they are likely to encounter. 相似文献