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Sample records for suction feeding fishes

  1. Morphology predicts suction feeding performance in centrarchid fishes.

    PubMed

    Carroll, Andrew M; Wainwright, Peter C; Huskey, Stephen H; Collar, David C; Turingan, Ralph G

    2004-10-01

    Suction feeding fish differ in their capacity to generate subambient pressure while feeding, and these differences appear to relate to morphological variation. We developed a morphological model of force transmission in the fish head and parameterized it with measurements from individual fish. The model was applied to 45 individuals from five species of centrarchid fishes: Lepomis macrochirus, Lepomis punctatus, Lepomis microlophus, Micropterus salmoides and Pomoxis nigromaculatus. Measurements of epaxial cross-sectional area, epaxial moment arm, buccal area and buccal area moment arm were combined to estimate pressure generation capacity for individual fish. This estimation was correlated with pressure measured in fish feeding on elusive prey to test the model's ability to predict pressure generation from morphology. The model explained differences in pressure generation found among individuals (P<0.001, r2=0.71) and produced a realistic estimate of normalized muscle stress during suction feeding (68.5+/-6.7 kPa). Fish with smaller mouths, larger epaxial cross-sectional area and longer epaxial moments, such as L. macrochirus (bluegill sunfish), generated lower pressures than fish with larger mouths, smaller cross-sectional area and shorter moments, such as M. salmoides (largemouth bass). These results reveal a direct trade-off between morphological requirements of feeding on larger prey (larger mouth size relative to body depth) and the ability to generate subambient pressure while suction feeding on elusive prey. PMID:15472018

  2. Body ram, not suction, is the primary axis of suction-feeding diversity in spiny-rayed fishes.

    PubMed

    Longo, Sarah J; McGee, Matthew D; Oufiero, Christopher E; Waltzek, Thomas B; Wainwright, Peter C

    2016-01-01

    Suction-feeding fishes exhibit diverse prey-capture strategies that vary in their relative use of suction and predator approach (ram), which is often referred to as the ram-suction continuum. Previous research has found that ram varies more than suction distance among species, such that ram accounts for most differences in prey-capture behaviors. To determine whether these findings hold at broad evolutionary scales, we collected high-speed videos of 40 species of spiny-rayed fishes (Acanthomorpha) feeding on live prey. For each strike, we calculated the contributions of suction, body ram (swimming) and jaw ram (mouth movement relative to the body) to closing the distance between predator and prey. We confirm that the contribution of suction distance is limited even in this phylogenetically and ecologically broad sample of species, with the extreme suction area of prey-capture space conspicuously unoccupied. Instead of a continuum from suction to ram, we find that variation in body ram is the major factor underlying the diversity of prey-capture strategies among suction-feeding fishes. Independent measurement of the contribution of jaw ram revealed that it is an important component of diversity among spiny-rayed fishes, with a number of ecomorphologies relying heavily on jaw ram, including pivot feeding in syngnathiforms, extreme jaw protruders and benthic sit-and-wait ambush predators. A combination of morphological and behavioral innovations has allowed fish to invade the extreme jaw ram area of prey-capture space. We caution that while two-species comparisons may support a ram-suction trade-off, these patterns do not speak to broader patterns across spiny-rayed fishes. PMID:26596534

  3. Energetic limitations on suction feeding performance in centrarchid fishes.

    PubMed

    Carroll, Andrew M; Wainwright, Peter C

    2009-10-01

    Energetic analysis of ecologically relevant behaviors can be useful because animals are energetically limited by available muscle mass. In this study we hypothesized that two major determinants of suction feeding performance, the magnitudes of buccal volumetric expansion and subambient buccal pressure, would be correlated with, and limited by, available muscle mass. At least four individuals of three centrarchid species were studied: largemouth bass (Micropterus salmoides), bluegill (Lepomis macrochirus) and green sunfish (Lepomis cyanellus). Buccal pressure was measured directly via cannulation of the buccal cavity with a catheter-tipped pressure transducer. Buccal expansion was estimated from lateral high-speed video (500 or 1000 Hz) sequences and published data on internal kinematics of largemouth bass. These estimates were calibrated from silicone casts made of the buccal cavity post-mortem. Estimated work and power were found to be significantly correlated with muscle mass over all individuals. The slopes of these relationships, estimates of mass-specific muscle work and power, were found to be 11+/-2 J kg(-1) and 300+/-75 W kg(-1), respectively. These estimates are consistent with observations made of in vivo and in vitro muscle use and with digital particle image velocimetry measurements of water flow in feeding centrarchids. A direct trade-off between mean pressure and change in volume was observed, when the latter was normalized to muscle mass. We conclude that available muscle mass may be a useful metric of suction feeding performance, and that the ratio of muscle mass to buccal volume may be a useful predictor of subambient buccal pressure magnitude. PMID:19801429

  4. Determining Suction Feeding Efficiency in the Bowfin fish (Amia) using Particle Image Velocimery and Computaional Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Rua, Yenny; Kharbouch, Karim; Sanford, Christopher; Reckinger, Shanon

    2014-11-01

    Suction feeding is the most common form of prey capture in aquatic vertebrates. During the early evolution of fishes there was a major change in shape of the mouth, from a wedge shaped mouth opening in more primitive fishes to a more circular and planar mouth. This change in shape resulted from increased mobility of a key upper jaw bone, the maxilla. It has been suggested that this change in shape dramatically increased suction feeding efficiency. This study examines the hydrodynamic effects of these two mouth shapes in the same animal, the bowfin fish (Amia calva). 2D Particle Image Velocimetry (PIV) is used to analyze suction feeding events. Post-processing algorithms have been developed to determine the flow rate of water into the mouth of the fish; the area of fluid, the velocity of fluid and the volume of fluid affected by the fish; the velocity of the fluid at the mouth, as well as the velocity of the fluid as a function of the distance from the mouth, finally the force exerted on the fluid by the fish is also determined. Lastly, a numerical model has been developed for comparison using a non-uniform mesh, which adapts dynamically in space and time to the fish feeding event. The realistic geometry of the fish's head is modeled in CAD.

  5. The pressures of suction feeding: the relation between buccal pressure and induced fluid speed in centrarchid fishes.

    PubMed

    Higham, Timothy E; Day, Steven W; Wainwright, Peter C

    2006-09-01

    Suction feeding fish rapidly expand their oral cavity, resulting in a flow of water directed towards the mouth that is accompanied by a drop in pressure inside the buccal cavity. Pressure inside the mouth and fluid speed external to the mouth are understood to be mechanically linked but the relationship between them has never been empirically determined in any suction feeder. We present the first simultaneous measurements of fluid speed and buccal pressure during suction feeding in fishes. Digital particle image velocimetry (DPIV) and high-speed video were used to measure the maximum fluid speed in front of the mouth of four largemouth bass and three bluegill sunfish by positioning a vertical laser sheet on the mid-sagittal plane of the fish. Peak magnitude of pressure inside the buccal cavity was quantified using a transducer positioned within a catheter that opened into the dorsal wall of the buccal cavity. In both species the time of peak pressure preceded the time of peak fluid speed by as much as 42 ms, indicating a role for unsteady flow effects in shaping this relation. We parameterized an existing model of suction feeding to determine whether the relationship between peak pressures and fluid speeds that we observed could be predicted using just a few kinematic variables. The model predicted much higher fluid speeds than we measured at all values of peak pressure and gave a scaling exponent between them (0.51) that was higher than observed (0.36 for largemouth bass, 0.38 for bluegill). The scaling between peak buccal pressure and peak fluid speed at the mouth aperture differed in the two species, supporting the recent conclusion that species morphology affects this relation such that a general pattern may not hold. PMID:16916963

  6. Hydroponic Feed With Suction

    NASA Technical Reports Server (NTRS)

    Cox, William M.; Brown, Christopher S.; Dreschel, Thomas W.

    1994-01-01

    Placing nutrient solution under suction increases growth. Foam plug seals growing stem of plant, making it possible to maintain suction in nutrient liquid around roots. Jar wrapped in black tape to keep out light. Potential use in terrestrial applications in arid climates or in labor-intensive agricultural situations.

  7. Multidimensional analysis of suction feeding performance in fishes: fluid speed, acceleration, strike accuracy and the ingested volume of water.

    PubMed

    Higham, Timothy E; Day, Steven W; Wainwright, Peter C

    2006-07-01

    Suction feeding fish draw prey into the mouth using a flow field that they generate external to the head. In this paper we present a multidimensional perspective on suction feeding performance that we illustrate in a comparative analysis of suction feeding ability in two members of Centrarchidae, the largemouth bass (Micropterus salmoides) and bluegill sunfish (Lepomis macrochirus). We present the first direct measurements of maximum fluid speed capacity, and we use this to calculate local fluid acceleration and volumetric flow rate. We also calculated the ingested volume and a novel metric of strike accuracy. In addition, we quantified for each species the effects of gape magnitude, time to peak gape, and swimming speed on features of the ingested volume of water. Digital particle image velocimetry (DPIV) and high-speed video were used to measure the flow in front of the mouths of three fish from each species in conjunction with a vertical laser sheet positioned on the mid-sagittal plane of the fish. From this we quantified the maximum fluid speed (in the earthbound and fish's frame of reference), acceleration and ingested volume. Our method for determining strike accuracy involved quantifying the location of the prey relative to the center of the parcel of ingested water. Bluegill sunfish generated higher fluid speeds in the earthbound frame of reference, accelerated the fluid faster, and were more accurate than largemouth bass. However, largemouth bass ingested a larger volume of water and generated a higher volumetric flow rate than bluegill sunfish. In addition, because largemouth bass swam faster during prey capture, they generated higher fluid speeds in the fish's frame of reference. Thus, while bluegill can exert higher drag forces on stationary prey items, largemouth bass more quickly close the distance between themselves and prey. The ingested volume and volumetric flow rate significantly increased as gape increased for both species, while time to peak

  8. Swimming muscles power suction feeding in largemouth bass

    PubMed Central

    Camp, Ariel L.; Roberts, Thomas J.; Brainerd, Elizabeth L.

    2015-01-01

    Most aquatic vertebrates use suction to capture food, relying on rapid expansion of the mouth cavity to accelerate water and food into the mouth. In ray-finned fishes, mouth expansion is both fast and forceful, and therefore requires considerable power. However, the cranial muscles of these fishes are relatively small and may not be able to produce enough power for suction expansion. The axial swimming muscles of these fishes also attach to the feeding apparatus and have the potential to generate mouth expansion. Because of their large size, these axial muscles could contribute substantial power to suction feeding. To determine whether suction feeding is powered primarily by axial muscles, we measured the power required for suction expansion in largemouth bass and compared it to the power capacities of the axial and cranial muscles. Using X-ray reconstruction of moving morphology (XROMM), we generated 3D animations of the mouth skeleton and created a dynamic digital endocast to measure the rate of mouth volume expansion. This time-resolved expansion rate was combined with intraoral pressure recordings to calculate the instantaneous power required for suction feeding. Peak expansion powers for all but the weakest strikes far exceeded the maximum power capacity of the cranial muscles. The axial muscles did not merely contribute but were the primary source of suction expansion power and generated up to 95% of peak expansion power. The recruitment of axial muscle power may have been crucial for the evolution of high-power suction feeding in ray-finned fishes. PMID:26100863

  9. Swimming muscles power suction feeding in largemouth bass.

    PubMed

    Camp, Ariel L; Roberts, Thomas J; Brainerd, Elizabeth L

    2015-07-14

    Most aquatic vertebrates use suction to capture food, relying on rapid expansion of the mouth cavity to accelerate water and food into the mouth. In ray-finned fishes, mouth expansion is both fast and forceful, and therefore requires considerable power. However, the cranial muscles of these fishes are relatively small and may not be able to produce enough power for suction expansion. The axial swimming muscles of these fishes also attach to the feeding apparatus and have the potential to generate mouth expansion. Because of their large size, these axial muscles could contribute substantial power to suction feeding. To determine whether suction feeding is powered primarily by axial muscles, we measured the power required for suction expansion in largemouth bass and compared it to the power capacities of the axial and cranial muscles. Using X-ray reconstruction of moving morphology (XROMM), we generated 3D animations of the mouth skeleton and created a dynamic digital endocast to measure the rate of mouth volume expansion. This time-resolved expansion rate was combined with intraoral pressure recordings to calculate the instantaneous power required for suction feeding. Peak expansion powers for all but the weakest strikes far exceeded the maximum power capacity of the cranial muscles. The axial muscles did not merely contribute but were the primary source of suction expansion power and generated up to 95% of peak expansion power. The recruitment of axial muscle power may have been crucial for the evolution of high-power suction feeding in ray-finned fishes. PMID:26100863

  10. Quantification of flow during suction feeding in bluegill sunfish.

    PubMed

    Ferry-Graham, Lara A; Wainwright, Peter C; Lauder, George V

    2003-01-01

    Nearly all aquatic-feeding vertebrates use some amount of suction to capture prey items. Suction prey capture occurs by accelerating a volume of water into the mouth and taking a prey item along with it. Yet, until recently, we lacked the necessary techniques and analytical tools to quantify the flow regime generated by feeding fish. We used a new approach; Digital Particle Image Velocimetery (DPIV) to measure several attributes of the flow generated by feeding bluegill sunfish. We found that the temporal pattern of flow was notably compressed during prey capture. Flow velocity increased rapidly to its peak within 20 ms of the onset of the strike, and this peak corresponded to the time that the prey entered the mouth during capture. The rapid acceleration and deceleration of water suggests that timing is critical for the predator in positioning itself relative to the prey so that it can be drawn into the mouth along with the water. We also found that the volume of water affected by suction was spatially limited. Only rarely did we measure significant flow beyond 1.75 cm of the mouth aperture (in 20 cm fish), further emphasizing the importance of mechanisms, like locomotion, that place the fish mouth in close proximity to the prey. We found that the highest flows towards the mouth along the fish midline were generated not immediately in front of the open mouth, but approximately 0.5 cm anterior to the mouth opening. Away from the midline the peak in flow was closer to the mouth. We propose that this pattern indicates the presence of a bow wave created by the locomotor efforts of the fish. In this scheme, the bow wave acts antagonistically to the flow of water generated by suction, the net effect being to push the region of peak flow away from the open mouth. The peak was located farther from the mouth opening in strikes accompanied by faster locomotion, suggesting faster fish created larger bow waves. PMID:16351901

  11. Characterization of zebrafish larvae suction feeding flow using μPIV and optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Pekkan, Kerem; Chang, Brian; Uslu, Fazil; Mani, Karthick; Chen, Chia-Yuan; Holzman, Roi

    2016-07-01

    The hydrodynamics of suction feeding is critical for the survival of fish larvae; failure to capture food during the onset of autonomous feeding can rapidly lead to starvation and mortality. Fluid mechanics experiments that investigate the suction feeding of suspended particles are limited to adult fishes, which operate at large Reynolds numbers. This manuscript presents the first literature results in which the external velocity fields generated during suction feeding of early zebrafish larvae (2500-20,000 μm total length) are reported using time-resolved microscopic particle image velocimetry. For the larval stages studied, the maximum peak suction velocity of the inflow bolus is measured at a finite distance from the mouth tip and ranges from 1 to 8 mm/s. The average pressure gradient and the velocity profile proximal to the buccal (mouth) cavity are calculated, and two distinct trends are identified. External recirculation regions and reverse flow feeding cycles are also observed and quantified. One of the unresolved questions in fish suction feeding is the shape and dynamics of the buccal cavity during suction feeding; optical coherence tomography imaging is found to be useful for reconstructing the mouth kinematics. The projected area of the mouth cavity during the feeding cycle varies up to 160 and 22 % for the transverse and mid-sagittal planes, respectively. These findings can inspire novel hydrodynamically efficient biomedical and microfluidic devices.

  12. Feeding kinematics, suction, and hydraulic jetting performance of harbor seals (Phoca vitulina).

    PubMed

    Marshall, Christopher D; Wieskotten, Sven; Hanke, Wolf; Hanke, Frederike D; Marsh, Alyssa; Kot, Brian; Dehnhardt, Guido

    2014-01-01

    The feeding kinematics, suction and hydraulic jetting capabilities of captive harbor seals (Phoca vitulina) were characterized during controlled feeding trials. Feeding trials were conducted using a feeding apparatus that allowed a choice between biting and suction, but also presented food that could be ingested only by suction. Subambient pressure exerted during suction feeding behaviors was directly measured using pressure transducers. The mean feeding cycle duration for suction-feeding events was significantly shorter (0.15±0.09 s; P<0.01) than biting feeding events (0.18±0.08 s). Subjects feeding in-water used both a suction and a biting feeding mode. Suction was the favored feeding mode (84% of all feeding events) compared to biting, but biting comprised 16% of feeding events. In addition, seals occasionally alternated suction with hydraulic jetting, or used hydraulic jetting independently, to remove fish from the apparatus. Suction and biting feeding modes were kinematically distinct regardless of feeding location (in-water vs. on-land). Suction was characterized by a significantly smaller gape (1.3±0.23 cm; P<0.001) and gape angle (12.9±2.02°), pursing of the rostral lips to form a circular aperture, and pursing of the lateral lips to occlude lateral gape. Biting was characterized by a large gape (3.63±0.21 cm) and gape angle (28.8±1.80°; P<0.001) and lip curling to expose teeth. The maximum subambient pressure recorded was 48.8 kPa. In addition, harbor seals were able to jet water at food items using suprambient pressure, also known as hydraulic jetting. The maximum hydraulic jetting force recorded was 53.9 kPa. Suction and hydraulic jetting where employed 90.5% and 9.5%, respectively, during underwater feeding events. Harbor seals displayed a wide repertoire of behaviorally flexible feeding strategies to ingest fish from the feeding apparatus. Such flexibility of feeding strategies and biomechanics likely forms the basis of their opportunistic

  13. Feeding Kinematics, Suction, and Hydraulic Jetting Performance of Harbor Seals (Phoca vitulina)

    PubMed Central

    Marshall, Christopher D.; Wieskotten, Sven; Hanke, Wolf; Hanke, Frederike D.; Marsh, Alyssa; Kot, Brian; Dehnhardt, Guido

    2014-01-01

    The feeding kinematics, suction and hydraulic jetting capabilities of captive harbor seals (Phoca vitulina) were characterized during controlled feeding trials. Feeding trials were conducted using a feeding apparatus that allowed a choice between biting and suction, but also presented food that could be ingested only by suction. Subambient pressure exerted during suction feeding behaviors was directly measured using pressure transducers. The mean feeding cycle duration for suction-feeding events was significantly shorter (0.15±0.09 s; P<0.01) than biting feeding events (0.18±0.08 s). Subjects feeding in-water used both a suction and a biting feeding mode. Suction was the favored feeding mode (84% of all feeding events) compared to biting, but biting comprised 16% of feeding events. In addition, seals occasionally alternated suction with hydraulic jetting, or used hydraulic jetting independently, to remove fish from the apparatus. Suction and biting feeding modes were kinematically distinct regardless of feeding location (in-water vs. on-land). Suction was characterized by a significantly smaller gape (1.3±0.23 cm; P<0.001) and gape angle (12.9±2.02°), pursing of the rostral lips to form a circular aperture, and pursing of the lateral lips to occlude lateral gape. Biting was characterized by a large gape (3.63±0.21 cm) and gape angle (28.8±1.80°; P<0.001) and lip curling to expose teeth. The maximum subambient pressure recorded was 48.8 kPa. In addition, harbor seals were able to jet water at food items using suprambient pressure, also known as hydraulic jetting. The maximum hydraulic jetting force recorded was 53.9 kPa. Suction and hydraulic jetting where employed 90.5% and 9.5%, respectively, during underwater feeding events. Harbor seals displayed a wide repertoire of behaviorally flexible feeding strategies to ingest fish from the feeding apparatus. Such flexibility of feeding strategies and biomechanics likely forms the basis of their opportunistic

  14. Effect of Feeding and Suction on Gastric Impedance Spectroscopy Measurements.

    PubMed

    Beltran, Nohra E; Sánchez-Miranda, Gustavo; Sacristan, Emilio

    2015-01-01

    A specific device and system has been developed and tested for clinical monitoring of gastric mucosal reactance in the critically ill as an early warning of splanchnic hypoperfusion associated with shock and sepsis. This device has been proven effective in clinical trials and is expected to become commercially available next year. The system uses a combination nasogastric tube and impedance spectroscopy probe as a single catheter. Because this device has a double function, the question is: Does enteral feeding or suction affect the gastric reactance measurements? This study was designed to evaluate the effect of feeding and suction on the measurement of gastric impedance spectroscopy in healthy volunteers. Impedance spectra were obtained from the gastric wall epithelia of 18 subjects. The spectra were measured for each of the following conditions: postinsertion of gastric probe, during active suction, postactive suction, and during enteral feeding (236 ml of nutritional supplement). Impedance spectra were reproducible in all volunteers under all conditions tested. There was a slight increase in impedance parameters after suction, and a decrease in impedance after feeding; however, these observed differences were insignificant compared to patient-to-patient variability, and truly negligible compared with previously observed changes associated with splanchnic ischemia in critically ill patients. Our results demonstrate that suction or feeding when using the impedance spectro-metry probe/nasogastric tube does not significantly interfere with gastric impedance spectrometer measurements. PMID:26226020

  15. Absence of Suction Feeding Ichthyosaurs and Its Implications for Triassic Mesopelagic Paleoecology

    PubMed Central

    Motani, Ryosuke; Ji, Cheng; Tomita, Taketeru; Kelley, Neil; Maxwell, Erin; Jiang, Da-yong; Sander, Paul Martin

    2013-01-01

    Mesozoic marine reptiles and modern marine mammals are often considered ecological analogs, but the extent of their similarity is largely unknown. Particularly important is the presence/absence of deep-diving suction feeders among Mesozoic marine reptiles because this would indicate the establishment of mesopelagic cephalopod and fish communities in the Mesozoic. A recent study suggested that diverse suction feeders, resembling the extant beaked whales, evolved among ichthyosaurs in the Triassic. However, this hypothesis has not been tested quantitatively. We examined four osteological features of jawed vertebrates that are closely linked to the mechanism of suction feeding, namely hyoid corpus ossification/calcification, hyobranchial apparatus robustness, mandibular bluntness, and mandibular pressure concentration index. Measurements were taken from 18 species of Triassic and Early Jurassic ichthyosaurs, including the presumed suction feeders. Statistical comparisons with extant sharks and marine mammals of known diets suggest that ichthyosaurian hyobranchial bones are significantly more slender than in suction-feeding sharks or cetaceans but similar to those of ram-feeding sharks. Most importantly, an ossified hyoid corpus to which hyoid retractor muscles attach is unknown in all but one ichthyosaur, whereas a strong integration of the ossified corpus and cornua of the hyobranchial apparatus has been identified in the literature as an important feature of suction feeders. Also, ichthyosaurian mandibles do not narrow rapidly to allow high suction pressure concentration within the oral cavity, unlike in beaked whales or sperm whales. In conclusion, it is most likely that Triassic and Early Jurassic ichthyosaurs were ‘ram-feeders’, without any beaked-whale-like suction feeder among them. When combined with the inferred inability for dim-light vision in relevant Triassic ichthyosaurs, the fossil record of ichthyosaurs does not suggest the establishment of modern

  16. Absence of suction feeding ichthyosaurs and its implications for triassic mesopelagic paleoecology.

    PubMed

    Motani, Ryosuke; Ji, Cheng; Tomita, Taketeru; Kelley, Neil; Maxwell, Erin; Jiang, Da-yong; Sander, Paul Martin

    2013-01-01

    Mesozoic marine reptiles and modern marine mammals are often considered ecological analogs, but the extent of their similarity is largely unknown. Particularly important is the presence/absence of deep-diving suction feeders among Mesozoic marine reptiles because this would indicate the establishment of mesopelagic cephalopod and fish communities in the Mesozoic. A recent study suggested that diverse suction feeders, resembling the extant beaked whales, evolved among ichthyosaurs in the Triassic. However, this hypothesis has not been tested quantitatively. We examined four osteological features of jawed vertebrates that are closely linked to the mechanism of suction feeding, namely hyoid corpus ossification/calcification, hyobranchial apparatus robustness, mandibular bluntness, and mandibular pressure concentration index. Measurements were taken from 18 species of Triassic and Early Jurassic ichthyosaurs, including the presumed suction feeders. Statistical comparisons with extant sharks and marine mammals of known diets suggest that ichthyosaurian hyobranchial bones are significantly more slender than in suction-feeding sharks or cetaceans but similar to those of ram-feeding sharks. Most importantly, an ossified hyoid corpus to which hyoid retractor muscles attach is unknown in all but one ichthyosaur, whereas a strong integration of the ossified corpus and cornua of the hyobranchial apparatus has been identified in the literature as an important feature of suction feeders. Also, ichthyosaurian mandibles do not narrow rapidly to allow high suction pressure concentration within the oral cavity, unlike in beaked whales or sperm whales. In conclusion, it is most likely that Triassic and Early Jurassic ichthyosaurs were 'ram-feeders', without any beaked-whale-like suction feeder among them. When combined with the inferred inability for dim-light vision in relevant Triassic ichthyosaurs, the fossil record of ichthyosaurs does not suggest the establishment of modern

  17. Independent Evolution of Suction Feeding in Neobatrachia: Feeding Mechanisms in Two Species of Telmatobius (Anura:Telmatobiidae).

    PubMed

    Barrionuevo, José Sebastián

    2016-02-01

    The most common feeding mechanism among aquatic vertebrates as fishes, turtles, and salamanders is inertial suction. However, among the more than 6,400 species of anurans, suction feeding occurs only in pipids. Pipidae is a small basal lineage relative to Neobatrachia, an enormous clade that contains about 96% of extant anurans. The Andean neobatrachian frogs of the genus Telmatobius include strictly aquatic and semiaquatic species. Diet analyses indicate that some species of Telmatobius feed on strictly aquatic prey, but until now their feeding mechanisms have been unknown. Herein, the feeding mechanisms in two species of Telmatobius, that represent the two predominant modes of life in the genus, are explored. The semiaquatic T. oxycephalus and the fully aquatic T. rubigo are studied using high-speed cinematography and standard anatomical techniques to provide a qualitative approach to feeding behavior and a detailed morphological description of the mouth, tongue, hyoid and related muscles. T. oxycephalus uses similar mechanisms of aquatic prey capture as do the vast majority of anurans that are capable of forage in water, whereas the fully aquatic T. rubigo is an inertial suction feeder. This is the first report of an objective record of this unique feeding behavior in a Neobatrachian. Several morphological characters seem to be related with this function and are convergent with those of pipids. PMID:26575038

  18. Feeding kinematics, suction and hydraulic jetting capabilities in bearded seals (Erignathus barbatus).

    PubMed

    Marshall, Christopher D; Kovacs, Kit M; Lydersen, Christian

    2008-03-01

    Feeding kinematics, suction and hydraulic jetting capabilities of bearded seals (Erignathus barbatus) were characterized during controlled feeding trials. Feeding trials were conducted both on land and in water, and allowed a choice between suction and biting, but food was also presented that could be ingested by suction alone. Four feeding phases, preparatory, jaw opening, hyoid depression and jaw closing were observed; the mean feeding cycle duration was 0.54+/-0.22 s, regardless of feeding mode (P>0.05). Subjects feeding on land used biting and suction 89.3% and 10.7% of the time, respectively. Subjects feeding in water used suction and hydraulic jetting 96.3% and 3.7% of the time, respectively. No biting behavior was observed underwater. Suction feeding was characterized by a small gape (2.7+/-0.85 cm), small gape angle (24.4+/-8.13 degrees ), pursing of the rostral lips to form a circular aperture, and pursing of the lateral lips to occlude lateral gape. Biting was characterized by large gape (7.3+/-2.2 cm), large gape angle (41.7+/-15.2 degrees ), and lip curling to expose the teeth. An excavation behavior in which suction and hydraulic jetting were alternated was used to extract food from recessed wells. The maximum subambient and suprambient pressures recorded were 91.2 and 53.4 kPa, respectively. The inclusion of suction data for phocids broadens the principle that suction feeding kinematics is conserved among aquatic vertebrates. Furthermore, bearded seals support predictions that mouth size, fluid flow speed, and elusiveness of prey consumed are among a suite of traits that determine the specific nature of suction feeding among species. PMID:18281332

  19. Short-Snouted Toothless Ichthyosaur from China Suggests Late Triassic Diversification of Suction Feeding Ichthyosaurs

    PubMed Central

    Sander, P. Martin; Chen, Xiaohong; Cheng, Long; Wang, Xiaofeng

    2011-01-01

    Background Ichthyosaurs were an important group of Mesozoic marine reptiles and existed from the Early Triassic to the early Late Cretaceous. Despite a great diversity in body shapes and feeding adaptations, all share greatly enlarged eyes, an elongated rostrum with numerous conical teeth, and a streamlined body. Methodology/Principal Findings Based on new material from China and the restudy of Shastasaurus pacificus, we here reinterpret the classical large-bodied Late Triassic ichthyosaur genus Shastasaurus to differ greatly from the standard ichthyosaurian body plan, indicating much greater morphological diversity and range of feeding adaptations in ichthyosaurs than previously recognized. Phylogenetic analysis indicates a monophyletic clade consisting of the giant Shonisaurus sikanniensis, Guanlingsaurus liangae, and Shastasaurus pacificus to which the genus name Shastasaurus is applied. Shastasaurus liangae comb. nov. is from the Late Triassic (Carnian) Xiaowa Formation of Guizhou Province, southwestern China. The species combines a diminutive head with an entirely toothless and greatly reduced snout. The species also has by far the highest vertebral count among ichthyosaurs (86 presacral vertebrae and >110 caudal vertebrae), a count that is also very high for tetrapods in general. A reduced toothless snout and a diminutive head is also apparently present in the giant S. sikanniensis and presumably in S. pacificus. Conclusions/Significance In analogy to many modern odontocetes, Shastasaurus is interpreted as a specialized suction feeder on unshelled cephalopods and fish, suggesting a unique but widespread Late Triassic diversification of toothless, suction-feeding ichthyosaurs. Suction feeding has not been hypothesized for any of the other diverse marine reptiles of the Mesozoic before, but in Shastasaurus may be linked to the Late Triassic minimum in atmospheric oxygen. PMID:21625429

  20. Scaling of suction-induced flows in bluegill: morphological and kinematic predictors for the ontogeny of feeding performance.

    PubMed

    Holzman, Roi; Collar, David C; Day, Steven W; Bishop, Kristin L; Wainwright, Peter C

    2008-08-01

    During ontogeny, animals undergo changes in size and shape that result in shifts in performance, behavior and resource use. These ontogenetic changes provide an opportunity to test hypotheses about how the growth of structures affects biological functions. In the present study, we ask how ontogenetic changes in skull biomechanics affect the ability of bluegill sunfish, a high-performance suction feeder, to produce flow speeds and accelerations during suction feeding. The flow of water in front of the mouth was measured directly for fish ranging from young-of-year to large adults, using digital particle imaging velocimetry (DPIV). As bluegill size increased, the magnitude of peak flow speed they produced increased, and the effective suction distance increased because of increasing mouth size. However, throughout the size range, the timing of peak fluid speed remained unchanged, and flow was constrained to approximately one gape distance from the mouth. The observed scaling relationships between standard length and peak flow speed conformed to expectations derived from two biomechanical models, one based on morphological potential to produce suction pressure (the Suction Index model) and the other derived from a combination of morphological and kinematic variables (the Expanding Cone model). The success of these models in qualitatively predicting the observed allometry of induced flow speed reveals that the scaling of cranial morphology underlies the scaling of suction performance in bluegill. PMID:18689419

  1. Modelled three-dimensional suction accuracy predicts prey capture success in three species of centrarchid fishes

    PubMed Central

    Kane, Emily A.; Higham, Timothy E.

    2014-01-01

    Prey capture is critical for survival, and differences in correctly positioning and timing a strike (accuracy) are likely related to variation in capture success. However, an ability to quantify accuracy under natural conditions, particularly for fishes, is lacking. We developed a predictive model of suction hydrodynamics and applied it to natural behaviours using three-dimensional kinematics of three centrarchid fishes capturing evasive and non-evasive prey. A spheroid ingested volume of water (IVW) with dimensions predicted by peak gape and ram speed was verified with known hydrodynamics for two species. Differences in capture success occurred primarily with evasive prey (64–96% success). Micropterus salmoides had the greatest ram and gape when capturing evasive prey, resulting in the largest and most elongate IVW. Accuracy predicted capture success, although other factors may also be important. The lower accuracy previously observed in M. salmoides was not replicated, but this is likely due to more natural conditions in our study. Additionally, we discuss the role of modulation and integrated behaviours in shaping the IVW and determining accuracy. With our model, accuracy is a more accessible performance measure for suction-feeding fishes, which can be used to explore macroevolutionary patterns of prey capture evolution. PMID:24718455

  2. A Solution Strategy to Include the Opening of the Opercular Slits in Moving-Mesh CFD Models of Suction Feeding.

    PubMed

    Van Wassenbergh, Sam

    2015-07-01

    The gill cover of fish and pre-metamorphic salamanders has a key role in suction feeding by acting as a one-way valve. It initially closes and avoids an inflow of water through the gill slits, after which it opens to allow outflow of the water that was sucked through the mouth into the expanded buccopharyngeal cavity. However, due to the inability of analytical models (relying on the continuity principle) to calculate the flow of fluid through a cavity with two openings and that was changing in shape and size, stringent boundary conditions had to be used in previously developed mathematical models after the moment of the valve's opening. By solving additionally for the conservation of momentum, computational fluid dynamics (CFD) has the capacity to dynamically simulate these flows, but this technique also faces complications in modeling a transition from closed to open valves. Here, I present a relatively simple solution strategy to incorporate the opening of the valves, exemplified in an axisymmetrical model of a suction-feeding sunfish in ANSYS Fluent software. By controlling viscosity of a separately defined fluid entity in the region of the opercular cavity, early inflow can be blocked (high viscosity assigned) and later outflow can be allowed (changing viscosity to that of water). Finally, by analyzing the CFD solution obtained for the sunfish model, a few new insights into the biomechanics of suction feeding are gained. PMID:25936359

  3. Aquatic feeding in pipid frogs: the use of suction for prey capture

    PubMed Central

    Carreño, Carrie A.; Nishikawa, Kiisa C.

    2010-01-01

    Inertial suction feeding is the most common method of prey capture among aquatic vertebrates. However, it had been unclear whether the aquatic frogs in the family Pipidae also used inertial suction for prey capture. In this study, we examined feeding behavior in four species of pipids, Pipa pipa, Xenopus laevis, Hymenochirus boettgeri and Pseudhymenochirus merlini. Pressure in the buccopharyngeal cavity was measured during prey capture. These pressure measurements were coupled with high-speed recordings of feeding behavior. For each species, the internal buccopharyngeal pressure was found to drop significantly below ambient pressure, and changes in pressure corresponded with the onset of mouth opening. Kinematic analysis revealed that all species of pipids generated subambient pressure during prey capture; H. boettgeri and P. merlini relied solely on inertial suction feeding. Pipa pipa and X. laevis additionally employed forelimb scooping during prey capture but both of these species demonstrated the ability to capture prey with inertial suction alone. Based on buccopharyngeal pressure measurements as well as kinematic analyses, we conclude that inertial suction feeding is used during prey capture in these four species of pipids. PMID:20511513

  4. Biomechanics and hydrodynamics of prey capture in the Chinese giant salamander reveal a high-performance jaw-powered suction feeding mechanism

    PubMed Central

    Heiss, Egon; Natchev, Nikolay; Gumpenberger, Michaela; Weissenbacher, Anton; Van Wassenbergh, Sam

    2013-01-01

    During the evolutionary transition from fish to tetrapods, a shift from uni- to bidirectional suction feeding systems followed a reduction in the gill apparatus. Such a shift can still be observed during metamorphosis of salamanders, although many adult salamanders retain their aquatic lifestyle and feed by high-performance suction. Unfortunately, little is known about the interplay between jaws and hyobranchial motions to generate bidirectional suction flows. Here, we study the cranial morphology, as well as kinematic and hydrodynamic aspects related to prey capture in the Chinese giant salamander (Andrias davidianus). Compared with fish and previously studied amphibians, A. davidianus uses an alternative suction mechanism that mainly relies on accelerating water by separating the ‘plates’ formed by the long and broad upper and lower jaw surfaces. Computational fluid dynamics simulations, based on three-dimensional morphology and kinematical data from high-speed videos, indicate that the viscerocranial elements mainly serve to accommodate the water that was given a sufficient anterior-to-posterior impulse beforehand by powerful jaw separation. We hypothesize that this modified way of generating suction is primitive for salamanders, and that this behaviour could have played an important role in the evolution of terrestrial life in vertebrates by releasing mechanical constraints on the hyobranchial system. PMID:23466557

  5. Bottom Feeding and Beyond: How the Premaxillary Protrusion of Cypriniforms Allowed for a Novel Kind of Suction Feeding.

    PubMed

    Hernandez, L Patricia; Staab, Katie Lynn

    2015-07-01

    While much of the functional work on suction feeding has involved members of Acanthopterygii, an earlier cypriniform radiation led to over 3200 species filling nearly every freshwater trophic niche. Within the great majority of acanthomorph clades that have been investigated suction feeding and the underlying morphology responsible for the generation of rapid suction have been largely conserved. This conserved feeding-apparatus is often associated with increasing the force experienced by the prey item, thus making a strike on elusive prey more effective. Cypriniforms' trophic anatomy is comprised of a number of novelties used for benthic feeding, which characterized early members of this clade. The modified cypriniform structure of the oral jaws represents a situation in which a particular type of suction feeding allowed for probing the benthos with a more functionally maneuverable anatomy. Requisite evolutionary modifications included origin and elongation of a median kinethmoid, duplications of certain divisions of the muscles of the adductor mandibulae, and origin of a dorsal, intra-buccal muscular palatal organ used in winnowing detritus. The elongated kinethmoid (coupled with modified adductor muscles) allowed for a type of premaxillary protrusion that decoupled the upper and lower jaws, enabled premaxillary protrusions with a closed mouth, and facilitated benthic feeding by increasing functional flexibility. The resultant flow of fluid generated by cypriniforms is also quite flexible, with multiple instances of peak flow in a single feeding event. This greatly modified morphology allowed for a degree of kinematic maneuverability not seen within most acanthomorphs. Later cypriniform radiations into piscivorous, insectivorous, or planktivorous feeding guilds were associated with shortening of the kinethmoid and with simplified morphology of the adductor, likely involving an emphasis on ram feeding. Although this suite of morphological novelties seemingly

  6. A Giant Chelonioid Turtle from the Late Cretaceous of Morocco with a Suction Feeding Apparatus Unique among Tetrapods

    PubMed Central

    Bardet, Nathalie; Jalil, Nour-Eddine; de Lapparent de Broin, France; Germain, Damien; Lambert, Olivier; Amaghzaz, Mbarek

    2013-01-01

    Background Secondary adaptation to aquatic life occurred independently in several amniote lineages, including reptiles during the Mesozoic and mammals during the Cenozoic. These evolutionary shifts to aquatic environments imply major morphological modifications, especially of the feeding apparatus. Mesozoic (250–65 Myr) marine reptiles, such as ichthyosaurs, plesiosaurs, mosasaurid squamates, crocodiles, and turtles, exhibit a wide range of adaptations to aquatic feeding and a broad overlap of their tooth morphospaces with those of Cenozoic marine mammals. However, despite these multiple feeding behavior convergences, suction feeding, though being a common feeding strategy in aquatic vertebrates and in marine mammals in particular, has been extremely rarely reported for Mesozoic marine reptiles. Principal Findings A relative of fossil protostegid and dermochelyoid sea turtles, Ocepechelon bouyai gen. et sp. nov. is a new giant chelonioid from the Late Maastrichtian (67 Myr) of Morocco exhibiting remarkable adaptations to marine life (among others, very dorsally and posteriorly located nostrils). The 70-cm-long skull of Ocepechelon not only makes it one of the largest marine turtles ever described, but also deviates significantly from typical turtle cranial morphology. It shares unique convergences with both syngnathid fishes (unique long tubular bony snout ending in a rounded and anteriorly directed mouth) and beaked whales (large size and elongated edentulous jaws). This striking anatomy suggests extreme adaptation for suction feeding unmatched among known turtles. Conclusion/Significance The feeding apparatus of Ocepechelon, a bony pipette-like snout, is unique among tetrapods. This new taxon exemplifies the successful systematic and ecological diversification of chelonioid turtles during the Late Cretaceous. This new evidence for a unique trophic specialization in turtles, along with the abundant marine vertebrate faunas associated to Ocepechelon in the Late

  7. Odontocete suction feeding: Experimental analysis of water flow and head shape.

    PubMed

    Werth, Alexander J

    2006-12-01

    The role of cranial morphology in the generation of intraoral and oropharyngeal suction pressures in odontocetes was investigated by manipulating the jaw and hyolingual apparatus of submerged heads of three species presenting varied shapes. Hyoid and gular muscles were manually employed to depress and retract the tongue. Pressures were recorded at three locations in the oral cavity, as gape and site, speed, and force of pull were varied. A biomechanical model was also developed to evaluate pressure data. The species with the shortest, bluntest head and smallest mouth opening generated greater negative pressures. Suction generation diminished sharply as gape increased. Greatest negative pressures attained were around -45 mmHg (-6,000 Pa), a magnitude deemed suitable for capture of small live prey. Odontocetes utilizing this bidirectional flow system should profit by evolution of a rounder mouth opening through progressive shortening and widening of the rostrum and jaws, a trend evident in cranial measurements from fossil and recent odontocetes. Blunt heads correlate with anatomical, ecological, and behavioral traits associated with suction feeding. Small-gape suction (with minimally opened jaws) could be used by odontocetes of all head and oral shapes to draw prey sufficiently close to the mouth for suction ingestion or grasping via dentition. Principal limitations of the experimental and mathematical simulations include assumption of a stationary odontocete with static (open or closed) jaws and potential scaling issues with differently sized heads and gapes. PMID:17103391

  8. Nutrition, feeding, and behavior of fish.

    PubMed

    Lall, Santosh P; Tibbetts, Sean M

    2009-05-01

    Nutrition and feeding influence growth, reproduction, and health of fish and their response to physiologic and environmental stressors and pathogens. The basics of fish metabolism are similar to those of warm-blooded animals in that they involve food intake, digestion, absorption, and transport of nutrients to the various tissues. Fish, however, being the most primitive form of vertebrates, possess some distinguishing features which will be discussed. Unlike warm-blooded animals, which are homoeothermic, fish are poikilothermic, so their body temperature and metabolic rate depends on the water temperature and this has practical implications for the nutrition, feeding and health of fish. Several behavioral responses have been linked to methods of feeding, feeding habits, frequency of feeding, mechanisms of food detection, and food preferences. Fish are also unique among vertebrates in their ability to absorb minerals not only from their diets but also from water through their gills and skin. PMID:19341962

  9. Suction among pickers: jaw mechanics, dietary breadth and feeding behaviour in beach-spawning Leuresthes spp. compared with their relatives.

    PubMed

    Higgins, B A; Horn, M H

    2014-06-01

    Jaw mechanics and dietary breadth in California grunion Leuresthes tenuis and Gulf grunion Leuresthes sardina were compared with three other members of the tribe Atherinopsini to test whether these two species have evolved a novel jaw protrusion that might be associated with feeding narrowly on abundant prey near spawning beaches. Quantitative comparison of cleared-and-stained specimens of five members of the atherinopsine clade showed that, compared with false grunion Colpichthys regis, topsmelt Atherinops affinis and jacksmelt Atherinopsis californiensis, L. tenuis and L. sardina have longer, more downwardly directed premaxillary protrusion, expanded dentary and premaxillary bones, greater lower jaw rotation and larger premaxilla-vomer separation. Leuresthes tenuis showed greater differences than L. sardina in these features. Comparison of the gut contents of L. tenuis and A. affinis with zooplankton samples collected simultaneously with these fishes in the water column within 1 km of shore showed that, as predicted, L. tenuis fed predominantly on mysid crustaceans and had a narrower diet than A. affinis. High-speed video analysis showed that L. tenuis exhibits a mean time to maximum jaw protrusion c. 2.5 times shorter than that of A. affinis. The grunion sister species, especially L. tenuis, have evolved suction feeding that may allow efficient feeding on common, evasive prey near spawning sites. The morphological traits seen in both species of Leuresthes signify a marked difference from their closest relatives in prey capture and suggest a type of jaw protrusion not yet seen in cyprinodontiforms or perciforms. PMID:24787078

  10. Fish consumption and track to a fish feed formulation

    NASA Astrophysics Data System (ADS)

    Cai-Juan, Soong; Ramli, Razamin; Rahman, Rosshairy Abdul

    2015-12-01

    Strategically located in the equator, Malaysia is blessed with plenty of fish supply. The high demand in fish consumption has helped the development in the fishery industry and provided numerous jobs in the secondary sector, contributing significantly to the nation's income. A survey was conducted to understand the trend of current demands for fish for the purpose of designing a feed formulation, which is still limited in this area of study. Results showed that grouper fish in restaurants commanded a very high price compared to other species of fish. Tiger grouper gained the highest demand in most restaurants, while giant grouper had the highest price in restaurants. Due to the demand and challenges to culture this type of fish, a framework for fish feed formulation is proposed. The formulation framework when materialized could be an alternative to the use of trash fish as the feed for grouper.

  11. Time management and nectar flow: flower handling and suction feeding in long-proboscid flies (Nemestrinidae: Prosoeca)

    NASA Astrophysics Data System (ADS)

    Karolyi, Florian; Morawetz, Linde; Colville, Jonathan F.; Handschuh, Stephan; Metscher, Brian D.; Krenn, Harald W.

    2013-11-01

    A well-developed suction pump in the head represents an important adaptation for nectar-feeding insects, such as Hymenoptera, Lepidoptera and Diptera. This pumping organ creates a pressure gradient along the proboscis, which is responsible for nectar uptake. The extremely elongated proboscis of the genus Prosoeca (Nemestrinidae) evolved as an adaptation to feeding from long, tubular flowers. According to the functional constraint hypothesis, nectar uptake through a disproportionately elongated, straw-like proboscis increases flower handling time and consequently lowers the energy intake rate. Due to the conspicuous length variation of the proboscis of Prosoeca, individuals with longer proboscides are hypothesised to have longer handling times. To test this hypothesis, we used field video analyses of flower-visiting behaviour, detailed examinations of the suction pump morphology and correlations of proboscis length with body length and suction pump dimensions. Using a biomechanical framework described for nectar-feeding Lepidoptera in relation to proboscis length and suction pump musculature, we describe and contrast the system in long-proboscid flies. Flies with longer proboscides spent significantly more time drinking from flowers. In addition, proboscis length and body length showed a positive allometric relationship. Furthermore, adaptations of the suction pump included an allometric relationship between proboscis length and suction pump muscle volume and a combination of two pumping organs. Overall, the study gives detailed insight into the adaptations required for long-proboscid nectar feeding, and comparisons with other nectar-sucking insects allow further considerations of the evolution of the suction pump in insects with sucking mouthparts.

  12. Electromyographic analysis of masseter muscle in newborns during suction in breast, bottle or cup feeding

    PubMed Central

    2014-01-01

    Background When breastfeeding is difficult or impossible during the neonatal period, an analysis of muscle activity can help determine the best method for substituting it to promote the child’s development. The aim of this study was to analyze the electrical activity of the masseter muscle using surface electromyography during suction in term newborns by comparing breastfeeding, bottle and cup feeding. Methods An observational, cross-sectional analytical study was carried out on healthy, clinically stable term infants, assigned to receive either breast, or bottle or cup feeding. Setting was a Baby Friendly accredited hospital. Muscle activity was analyzed when each infant showed interest in sucking using surface electromyography. Root mean square averages (RMS) recorded in microvolts were transformed into percentages (normalization) of the reference value. The three groups were compared by ANOVA; the “stepwise” method of the multiple linear regression analysis tested the model which best defined the activity of the masseter muscle in the sample at a significance level of 5%. Results Participants were 81 full term newborns (27 per group), from 2 to 28 days of life. RMS values were lower for bottle (mean 44.2%, SD 14.1) than breast feeding (mean 58.3%, SD 12.7) (P = 0.003, ANOVA); cup feeding (52.5%, SD 18.2%) was not significantly different (P > 0.05). For every gram of weight increase, RMS increased by 0.010 units. Conclusions Masseter activity was significantly higher in breastfed newborns than in bottle-fed newborns, who presented the lowest RMS values. Levels of masseter activity during cup-feeding were between those of breast and bottle feeding, and did not significantly differ from either group. This study in healthy full term neonates endorses cup rather than bottle feeding as a temporary substitute for breastfeeding. PMID:24885762

  13. Feeding Practices and Fish Health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the past three decades, the aquaculture industry has expanded rapidly throughout the world and is expected to continue to grow in the years to come due to the unpredictability and high cost of harvesting fish from the oceans as well as the increased demand for fish as a result of rapid populati...

  14. Australian Fur Seals (Arctocephalus pusillus doriferus) Use Raptorial Biting and Suction Feeding When Targeting Prey in Different Foraging Scenarios

    PubMed Central

    Hocking, David P.; Salverson, Marcia; Fitzgerald, Erich M. G.; Evans, Alistair R.

    2014-01-01

    Foraging behaviours used by two female Australian fur seals (Arctocephalus pusillus doriferus) were documented during controlled feeding trials. During these trials the seals were presented with prey either free-floating in open water or concealed within a mobile ball or a static box feeding device. When targeting free-floating prey both subjects primarily used raptorial biting in combination with suction, which was used to draw prey to within range of the teeth. When targeting prey concealed within either the mobile or static feeding device, the seals were able to use suction to draw out prey items that could not be reached by biting. Suction was followed by lateral water expulsion, where water drawn into the mouth along with the prey item was purged via the sides of the mouth. Vibrissae were used to explore the surface of the feeding devices, especially when locating the openings in which the prey items had been hidden. The mobile ball device was also manipulated by pushing it with the muzzle to knock out concealed prey, which was not possible when using the static feeding device. To knock prey out of this static device one seal used targeted bubble blowing, where a focused stream of bubbles was blown out of the nose into the openings in the device. Once captured in the jaws, prey items were manipulated and re-oriented using further mouth movements or chews so that they could be swallowed head first. While most items were swallowed whole underwater, some were instead taken to the surface and held in the teeth, while being vigorously shaken to break them into smaller pieces before swallowing. The behavioural flexibility displayed by Australian fur seals likely assists in capturing and consuming the extremely wide range of prey types that are targeted in the wild, during both benthic and epipelagic foraging. PMID:25390347

  15. Australian fur seals (Arctocephalus pusillus doriferus) use raptorial biting and suction feeding when targeting prey in different foraging scenarios.

    PubMed

    Hocking, David P; Salverson, Marcia; Fitzgerald, Erich M G; Evans, Alistair R

    2014-01-01

    Foraging behaviours used by two female Australian fur seals (Arctocephalus pusillus doriferus) were documented during controlled feeding trials. During these trials the seals were presented with prey either free-floating in open water or concealed within a mobile ball or a static box feeding device. When targeting free-floating prey both subjects primarily used raptorial biting in combination with suction, which was used to draw prey to within range of the teeth. When targeting prey concealed within either the mobile or static feeding device, the seals were able to use suction to draw out prey items that could not be reached by biting. Suction was followed by lateral water expulsion, where water drawn into the mouth along with the prey item was purged via the sides of the mouth. Vibrissae were used to explore the surface of the feeding devices, especially when locating the openings in which the prey items had been hidden. The mobile ball device was also manipulated by pushing it with the muzzle to knock out concealed prey, which was not possible when using the static feeding device. To knock prey out of this static device one seal used targeted bubble blowing, where a focused stream of bubbles was blown out of the nose into the openings in the device. Once captured in the jaws, prey items were manipulated and re-oriented using further mouth movements or chews so that they could be swallowed head first. While most items were swallowed whole underwater, some were instead taken to the surface and held in the teeth, while being vigorously shaken to break them into smaller pieces before swallowing. The behavioural flexibility displayed by Australian fur seals likely assists in capturing and consuming the extremely wide range of prey types that are targeted in the wild, during both benthic and epipelagic foraging. PMID:25390347

  16. A biorobotic model of the suction-feeding system in largemouth bass: the roles of motor program speed and hyoid kinematics.

    PubMed

    Kenaley, Christopher P; Lauder, George V

    2016-07-01

    The vast majority of ray-finned fishes capture prey through suction feeding. The basis of this behavior is the generation of subambient pressure through rapid expansion of a highly kinetic skull. Over the last four decades, results from in vivo experiments have elucidated the general relationships between morphological parameters and subambient pressure generation. Until now, however, researchers have been unable to tease apart the discrete contributions of, and complex relationships among, the musculoskeletal elements that support buccal expansion. Fortunately, over the last decade, biorobotic models have gained a foothold in comparative research and show great promise in addressing long-standing questions in vertebrate biomechanics. In this paper, we present BassBot, a biorobotic model of the head of the largemouth bass (Micropterus salmoides). BassBot incorporates a 3D acrylic plastic armature of the neurocranium, maxillary apparatus, lower jaw, hyoid, suspensorium and opercular apparatus. Programming of linear motors permits precise reproduction of live kinematic behaviors including hyoid depression and rotation, premaxillary protrusion, and lateral expansion of the suspensoria. BassBot reproduced faithful kinematic and pressure dynamics relative to live bass. We show that motor program speed has a direct relationship to subambient pressure generation. Like vertebrate muscle, the linear motors that powered kinematics were able to produce larger magnitudes of force at slower velocities and, thus, were able to accelerate linkages more quickly and generate larger magnitudes of subambient pressure. In addition, we demonstrate that disrupting the kinematic behavior of the hyoid interferes with the anterior-to-posterior expansion gradient. This resulted in a significant reduction in subambient pressure generation and pressure impulse of 51% and 64%, respectively. These results reveal the promise biorobotic models have for isolating individual parameters and assessing

  17. New fossil insect order Permopsocida elucidates major radiation and evolution of suction feeding in hemimetabolous insects (Hexapoda: Acercaria).

    PubMed

    Huang, Di-Ying; Bechly, Günter; Nel, Patricia; Engel, Michael S; Prokop, Jakub; Azar, Dany; Cai, Chen-Yang; van de Kamp, Thomas; Staniczek, Arnold H; Garrouste, Romain; Krogmann, Lars; Dos Santos Rolo, Tomy; Baumbach, Tilo; Ohlhoff, Rainer; Shmakov, Alexey S; Bourgoin, Thierry; Nel, André

    2016-01-01

    With nearly 100,000 species, the Acercaria (lice, plant lices, thrips, bugs) including number of economically important species is one of the most successful insect lineages. However, its phylogeny and evolution of mouthparts among other issues remain debatable. Here new methods of preparation permitted the comprehensive anatomical description of insect inclusions from mid-Cretaceous Burmese amber in astonishing detail. These "missing links" fossils, attributed to a new order Permopsocida, provide crucial evidence for reconstructing the phylogenetic relationships in the Acercaria, supporting its monophyly, and questioning the position of Psocodea as sister group of holometabolans in the most recent phylogenomic study. Permopsocida resolves as sister group of Thripida + Hemiptera and represents an evolutionary link documenting the transition from chewing to piercing mouthparts in relation to suction feeding. Identification of gut contents as angiosperm pollen documents an ecological role of Permopsocida as early pollen feeders with relatively unspecialized mouthparts. This group existed for 185 million years, but has never been diverse and was superseded by new pollenivorous pollinators during the Cretaceous co-evolution of insects and flowers. The key innovation of suction feeding with piercing mouthparts is identified as main event that triggered the huge post-Carboniferous radiation of hemipterans, and facilitated the spreading of pathogenic vectors. PMID:26961785

  18. New fossil insect order Permopsocida elucidates major radiation and evolution of suction feeding in hemimetabolous insects (Hexapoda: Acercaria)

    PubMed Central

    Huang, Di-Ying; Bechly, Günter; Nel, Patricia; Engel, Michael S.; Prokop, Jakub; Azar, Dany; Cai, Chen-Yang; van de Kamp, Thomas; Staniczek, Arnold H.; Garrouste, Romain; Krogmann, Lars; dos Santos Rolo, Tomy; Baumbach, Tilo; Ohlhoff, Rainer; Shmakov, Alexey S.; Bourgoin, Thierry; Nel, André

    2016-01-01

    With nearly 100,000 species, the Acercaria (lice, plant lices, thrips, bugs) including number of economically important species is one of the most successful insect lineages. However, its phylogeny and evolution of mouthparts among other issues remain debatable. Here new methods of preparation permitted the comprehensive anatomical description of insect inclusions from mid-Cretaceous Burmese amber in astonishing detail. These “missing links” fossils, attributed to a new order Permopsocida, provide crucial evidence for reconstructing the phylogenetic relationships in the Acercaria, supporting its monophyly, and questioning the position of Psocodea as sister group of holometabolans in the most recent phylogenomic study. Permopsocida resolves as sister group of Thripida + Hemiptera and represents an evolutionary link documenting the transition from chewing to piercing mouthparts in relation to suction feeding. Identification of gut contents as angiosperm pollen documents an ecological role of Permopsocida as early pollen feeders with relatively unspecialized mouthparts. This group existed for 185 million years, but has never been diverse and was superseded by new pollenivorous pollinators during the Cretaceous co-evolution of insects and flowers. The key innovation of suction feeding with piercing mouthparts is identified as main event that triggered the huge post-Carboniferous radiation of hemipterans, and facilitated the spreading of pathogenic vectors. PMID:26961785

  19. Raising the Sugar Content – Orchid Bees Overcome the Constraints of Suction Feeding through Manipulation of Nectar and Pollen Provisions

    PubMed Central

    Pokorny, Tamara; Lunau, Klaus; Eltz, Thomas

    2014-01-01

    Unlike most other bees, the long-tongued orchid bees ingest nectar using suction feeding. Although long tongues allow exploitation of flowers with deep spurs, the energy intake rate is optimal at 10–20% lower nectar sugar concentrations compared to that of lapping bees. This constraint might be compensated by a higher digestive throughput. Additionally, orchid bees might evaporate water from regurgitated droplets of crop contents. We found male Euglossa championi (n = 10) and Euglossa dodsoni (n = 12) to regularly regurgitate droplets of crop content to the base of their proboscis, generating a fluid film between the proximal parts of the galeae, glossa and labial palps. Rhythmic movements of the proboscis may help to increase convection. There was a significant change in sugar concentration between the initially imbibed solution and the resulting crop content (P<0.05) and the time individual bees had engaged in this liquid exposure behavior was positively correlated with the resulting crop sugar concentration. Female Euglossa townsendi and Euglossa viridissima showed the same behavior. Additionally, they manipulated their nectar-enriched pollen provisions for extensive periods of time before deposition in brood cells. The deposited pollen loads (n = 14) showed a significantly higher sugar concentration than the sugar-water available to the bees (P<0.001). Thus, both male and female euglossines show behaviors that promote evaporative water loss from nectar. We suggest that the behaviors have evolved in concert with suction feeding on dilute nectar from deep floral tubes. PMID:25422945

  20. Persistent halogenated hydrocarbons in fish feeds manufactured in South China.

    PubMed

    Guo, Ying; Yu, Huan-Yun; Zhang, Bao-Zhong; Zeng, Eddy Y

    2009-05-13

    Persistent halogenated hydrocarbons (PHHs), including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs), in fish feeds (including trash fish and compound feed) manufactured in South China, were analyzed. PHHs were ubiquitous in fish feeds, with the concentrations of OCPs, PBDEs, and PCBs at the upper, mid, and lower levels of the global range. Trash fish generally contained higher concentrations of DDXs (sum of o,p'- and p,p'-DDT, -DDD, and -DDE and p,p'-DDMU), especially p,p'-DDT and low-brominated PBDEs, while compound feeds had higher concentrations of highly brominated BDEs, e.g., BDE-209. In addition, no concentration difference of HCHs and PCBs was found between trash fish and compound feeds. The habit of direct use of trash fish as fish feeds has induced the accumulation of DDXs in aquatic species in China, and trash fish collected in South China seemed to be slightly hazardous to wildlife because of the concentrations of DDXs. The results from the present study suggest that the use pattern of fish feeds in China may have to be adjusted to minimize contamination of fishery products and wildlife by PHHs. Use of compound feeds produced with controlled procedures should be encouraged, whereas that of trash fish should be restricted, at least for now. PMID:19326952

  1. PCBs and DDE in commercial fish feeds

    USGS Publications Warehouse

    Mac, Michael J.; Nicholson, L.W.; McCauley, C.A.

    1979-01-01

    Three commercial fish feeds were analyzed for PCBs and p,p' DDE and were reported in dry weight concentrations. In various sizes of Oregon Moist Pellets, concentrations of PCBs ranged from less than 0.10 to 0.30 I?g/g and those of p,p' DDE from less than 0.01 to 0.47 I?g/g. In Silver Cup, concentrations of PCBs were 0.06 to 0.07 I?g/g, and p,p' DDE, 0.01 to 0.06 I?g/g. Nauplii of brine shrimp (Artemia salina) contained 0.14 I?g/g PCB and 0.03 I?g/g p,p' DDE.

  2. A fish that uses its hydrodynamic tongue to feed on land.

    PubMed

    Michel, Krijn B; Heiss, Egon; Aerts, Peter; Van Wassenbergh, Sam

    2015-04-22

    To capture and swallow food on land, a sticky tongue supported by the hyoid and gill arch skeleton has evolved in land vertebrates from aquatic ancestors that used mouth-cavity-expanding actions of the hyoid to suck food into the mouth. However, the evolutionary pathway bridging this drastic shift in feeding mechanism and associated hyoid motions remains unknown. Modern fish that feed on land may help to unravel the physical constraints and biomechanical solutions that led to terrestrialization of fish-feeding systems. Here, we show that the mudskipper emerges onto land with its mouth cavity filled with water, which it uses as a protruding and retracting 'hydrodynamic tongue' during the initial capture and subsequent intra-oral transport of food. Our analyses link this hydrodynamic action of the intra-oral water to a sequence of compressive and expansive cranial motions that diverge from the general pattern known for suction feeding in fishes. However, the hyoid motion pattern showed a remarkable resemblance to newts during tongue prehension. Consequently, although alternative scenarios cannot be excluded, hydrodynamic tongue usage may be a transitional step onto which the evolution of adhesive mucosa and intrinsic lingual muscles can be added to gain further independence from water for terrestrial foraging. PMID:25788596

  3. A fish that uses its hydrodynamic tongue to feed on land

    PubMed Central

    Michel, Krijn B.; Heiss, Egon; Aerts, Peter; Van Wassenbergh, Sam

    2015-01-01

    To capture and swallow food on land, a sticky tongue supported by the hyoid and gill arch skeleton has evolved in land vertebrates from aquatic ancestors that used mouth-cavity-expanding actions of the hyoid to suck food into the mouth. However, the evolutionary pathway bridging this drastic shift in feeding mechanism and associated hyoid motions remains unknown. Modern fish that feed on land may help to unravel the physical constraints and biomechanical solutions that led to terrestrialization of fish-feeding systems. Here, we show that the mudskipper emerges onto land with its mouth cavity filled with water, which it uses as a protruding and retracting ‘hydrodynamic tongue’ during the initial capture and subsequent intra-oral transport of food. Our analyses link this hydrodynamic action of the intra-oral water to a sequence of compressive and expansive cranial motions that diverge from the general pattern known for suction feeding in fishes. However, the hyoid motion pattern showed a remarkable resemblance to newts during tongue prehension. Consequently, although alternative scenarios cannot be excluded, hydrodynamic tongue usage may be a transitional step onto which the evolution of adhesive mucosa and intrinsic lingual muscles can be added to gain further independence from water for terrestrial foraging. PMID:25788596

  4. Unexpectedly high mercury level in pelleted commercial fish feed

    SciTech Connect

    Choi, M.H.; Cech, J.J. Jr.

    1998-10-01

    An unexpectedly high mercury (Hg) level was found in a pelleted commercial fish feed used to feed fish in laboratory and fish farm settings. Mean total Hg (T-Hg) concentration in the commercial fish pellets was 66 ppb. Mean total selenium (T-Se) concentration in the pellets was 1,120 ppb (ranging from 790 to 1,360 ppb). Total Hg and Se in the whole blood of Sacramento blackfish and in the fish feed were determined by inductively coupled plasma-mass spectrometry (ICP-MS). During a 10-week sampling period T-Hg in blood fluctuated between 35 and 56 ppb. A highly significant, positive correlation was found between T-Hg in the fish blood and in the fish feed through the sampling period. On the other hand, no correlation was found between T-Se in the fish feed and T-Hg or T-Se blood level. Researchers working with fish in Hg studies need to know that fish pellets may contain Hg and to consider the influence of these pellets in their results.

  5. Liparid and macrourid fishes of the hadal zone: in situ observations of activity and feeding behaviour

    PubMed Central

    Jamieson, A.J.; Fujii, T.; Solan, M.; Matsumoto, A.K.; Bagley, P.M.; Priede, I.G.

    2008-01-01

    Using baited camera landers, the first images of living fishes were recorded in the hadal zone (6000–11 000 m) in the Pacific Ocean. The widespread abyssal macrourid Coryphaenoides yaquinae was observed at a new depth record of approximately 7000 m in the Japan Trench. Two endemic species of liparid were observed at similar depths: Pseudoliparis amblystomopsis in the Japan Trench and Notoliparis kermadecensis in the Kermadec Trench. From these observations, we have documented swimming and feeding behaviour of these species and derived the first estimates of hadal fish abundance. The liparids intercepted bait within 100–200 min but were observed to preferentially feed on scavenging amphipods. Notoliparis kermadecensis act as top predators in the hadal food web, exhibiting up to nine suction-feeding events per minute. Both species showed distinctive swimming gaits: P. amblystomopsis (mean length 22.5 cm) displayed a mean tail-beat frequency of 0.47 Hz and mean caudal : pectoral frequency ratio of 0.76, whereas N. kermadecensis (mean length 31.5 cm) displayed respective values of 1.04 and 2.08 Hz. Despite living at extreme depths, these endemic liparids exhibit similar activity levels compared with shallow-water liparids. PMID:19129104

  6. Liparid and macrourid fishes of the hadal zone: in situ observations of activity and feeding behaviour.

    PubMed

    Jamieson, A J; Fujii, T; Solan, M; Matsumoto, A K; Bagley, P M; Priede, I G

    2009-03-22

    Using baited camera landers, the first images of living fishes were recorded in the hadal zone (6000-11000 m) in the Pacific Ocean. The widespread abyssal macrourid Coryphaenoides yaquinae was observed at a new depth record of approximately 7000 m in the Japan Trench. Two endemic species of liparid were observed at similar depths: Pseudoliparis amblystomopsis in the Japan Trench and Notoliparis kermadecensis in the Kermadec Trench. From these observations, we have documented swimming and feeding behaviour of these species and derived the first estimates of hadal fish abundance. The liparids intercepted bait within 100-200 min but were observed to preferentially feed on scavenging amphipods. Notoliparis kermadecensis act as top predators in the hadal food web, exhibiting up to nine suction-feeding events per minute. Both species showed distinctive swimming gaits: P. amblystomopsis (mean length 22.5 cm) displayed a mean tail-beat frequency of 0.47 Hz and mean caudal:pectoral frequency ratio of 0.76, whereas N. kermadecensis (mean length 31.5 cm) displayed respective values of 1.04 and 2.08 Hz. Despite living at extreme depths, these endemic liparids exhibit similar activity levels compared with shallow-water liparids. PMID:19129104

  7. Mercury and stable isotope signatures in caged marine fish and fish feeds.

    PubMed

    Onsanit, Sarayut; Chen, Min; Ke, Caihuan; Wang, Wen-Xiong

    2012-02-15

    Total mercury (THg) and methylmercury (MeHg) concentrations were determined in four species of marine caged carnivorous fish, one species of herbivorous fish and three types of fish feeds (dried pellet feed, forage fish and fish viscera), collected from five cage sites in the rural areas along Fujian coastline, China. For the carnivorous fish, the concentrations of THg and MeHg ranged from 0.03 to 0.31 μg/g and from 0.02 to 0.30 μg/g on wet weight basis, respectively. The concentrations were lower for the herbivorous fish with both within the range of 0.01-0.03 μg/g. Out of the three tested fish feeds, tuna viscera contained the highest level of mercury (0.20 μg/g THg and 0.13 μg/g MeHg), with pellet feed containing the lowest level (0.05 μg/g THg and 0.01 μg/g MeHg). The calculated trophic transfer factor of MeHg was the highest (12-64) for fish fed on pellet feeds, and was the lowest for fish fed on tuna viscera. A significant relationship was found between Hg concentrations in caged fish and in fish feeds, thus Hg was primarily accumulated from the diet. Furthermore, the stable isotope δ(15)N was positively correlated with the Hg concentration in two caged sites, indicating that δ(15)N may be a suitable tool for tracking mercury in caged fish. We conclude that fish farming may be a good way of reducing the human exposure to Hg because mercury levels can be carefully controlled in such farming systems. PMID:22195524

  8. [Detection of fish DNA in ruminant feed by PCR amplification].

    PubMed

    Nomura, Tetsuya; Kusama, Toyoko; Kadowaki, Koh-ichi

    2006-10-01

    The Japanese Government has prohibited the use of seafood protein, as well as mammalian protein, in ruminant feed. There is an official method to detect meat and bone meal, but no method is yet available to detect fishmeal in ruminant feed. We tried to develop a suitable method to detect fishmeal in ruminant feed, similar to the official method "PCR detection of animal-derived DNA in feed". Our previously reported primers (fishcon5 and fishcon3-1) showed low sensitivity, so we designed new primers based on a DNA sequence from yellowfin tuna mitchondrial DNA. Among the primers, FM5 and FM3 specifically detected fish DNA (sardine, yellowfin tuna, skipjack tuna, chub mackerel, Pacific saury, salmon, rainbow trout, Japanese anchovy, codfish and Japanese horse mackerel) from fish meat, and did not amplify DNA from animals and plants. The sensitivity for detection of the presence of fishmeal in ruminant feed was 0.01-0.001%. PMID:17128872

  9. [Selective feeding in fish: Effect of feeding and defensive motivations evoked by natural odors].

    PubMed

    Kasumyan, A O; Marusov, E A

    2015-01-01

    The effect of feeding and defensive motivations evoked by natural olfactory signals (the food odor, the alarm pheromone) on choice and consumption of food items different in color and taste, and the manifestation of foraging behavior were examined in fish (koi Cyprinus carpio, roach Rutilus rutilus). The agar-agar pellets of red and green color having one of the amino acids (glycine, L-proline, L-alanine; all in concentration of 0.1 M) were simultaneously offered to single fishes in pure water, and in water extract of Chironomidae larvae or in water extract of fish skin. It was found out that odors used have different effects on fish foraging activity and on pellet selection for both pellet choice and consumption. On background of food odor, fish grasped pellets more often than in pure water. The equal choice of red and green pellets in pure water shifted to the preference of red ones in the presence of food odor. Despite the increase in the absolute number of pellets grasped, the relative consumption reduced and was replaced by selective consumption of pellets with glycine regardless of their color. Increasing demand for the food quality, due to the increased feeding motivation in response to food odor, is an important adaptation enhancing selection and consumption of food with more appropriate sensory qualities for fish. Defensive motivation caused by alarm pheromone suppressed predisposition. of fish to feed. Fish grasped pellets several times less often than in pure water and refused most of them. Any changes in the color or taste preferences were absent. Feeding behavior of fish of both species was characterized by repeated intraoral pellet testing, but in koi handling was less typical than in roach. In both species, handling activity was higher in those cases when the pellet was finally rejected. This activity was enhanced also on the background of food odor. PMID:26201217

  10. Feeding diets and significance of coral feeding among Chaetodontid fishes in Moorea (French Polynesia)

    NASA Astrophysics Data System (ADS)

    Harmelin-Vivien, M. L.; Bouchon-Navaro, Y.

    1983-06-01

    The feeding diets of 18 Chaetodontid fishes from a coral reef of Moorea (French Polynesia) were studied by quantitative analysis of their stomach contents. Three major types of feeding behaviours were distinguished. Sixteen species essentially ingested coral polyps. Among these species, 5 were exclusive coral browsers and the others displayed more heterogeneous diets. One species was a plankton feeder and the other consumed benthic invertebrates other than corals. The importance of coral consumption on the reef by Chaetodontid fishes was estimated knowing the feeding diets and density of species in the various biota. Moreover, the species which were previously observed as quantitatively dominant in the different reef zones, were found to be exclusive coral browsers. Besides, the proportion between obligative and facultative coral feeders was found to be relatively constant on the reef, emphasizing that a balance is established among the Chaetodontid species occupying the same habitat for the resource partitioning.

  11. Suction generation in white-spotted bamboo sharks Chiloscyllium plagiosum.

    PubMed

    Wilga, Cheryl D; Sanford, Christopher P

    2008-10-01

    After the divergence of chondrichthyans and teleostomes, the structure of the feeding apparatus also diverged leading to alterations in the suction mechanism. In this study we investigated the mechanism for suction generation during feeding in white-spotted bamboo sharks, Chiloscyllium plagiosum and compared it with that in teleosts. The internal movement of cranial elements and pressure in the buccal, hyoid and pharyngeal cavities that are directly responsible for suction generation was quantified using sonomicrometry and pressure transducers. Backward stepwise multiple linear regressions were used to explore the relationship between expansion and pressure, accounting for 60-96% of the variation in pressure among capture events. The progression of anterior to posterior expansion in the buccal, hyoid and pharyngeal cavities is accompanied by the sequential onset of subambient pressure in these cavities as prey is drawn into the mouth. Gape opening triggers the onset of subambient pressure in the oropharyngeal cavities. Peak gape area coincides with peak subambient buccal pressure. Increased velocity of hyoid area expansion is primarily responsible for generating peak subambient pressure in the buccal and hyoid regions. Pharyngeal expansion appears to function as a sink to receive water influx from the mouth, much like that of compensatory suction in bidirectional aquatic feeders. Interestingly, C. plagiosum generates large suction pressures while paradoxically compressing the buccal cavity laterally, delaying the time to peak pressure. This represents a fundamental difference from the mechanism used to generate suction in teleost fishes. Interestingly, pressure in the three cavities peaks in the posterior to anterior direction. The complex shape changes that the buccal cavity undergoes indicate that, as in teleosts, unsteady flow predominates during suction feeding. Several kinematic variables function together, with great variation over long gape cycles to

  12. Effects of bottom trawling on fish foraging and feeding.

    PubMed

    Johnson, Andrew Frederick; Gorelli, Giulia; Jenkins, Stuart Rees; Hiddink, Jan Geert; Hinz, Hilmar

    2015-01-22

    The effects of bottom trawling on benthic invertebrates include reductions of biomass, diversity and body size. These changes may negatively affect prey availability for demersal fishes, potentially leading to reduced food intake, body condition and yield of fishes in chronically trawled areas. Here, the effect of trawling on the prey availability and diet of two commercially important flatfish species, plaice (Pleuronectes platessa) and dab (Limanda limanda), was investigated over a trawling intensity gradient in the Irish Sea. Previous work in this area has shown that trawling negatively affects the condition of plaice but not of dab. This study showed that reductions in local prey availability did not result in reduced feeding of fish. As trawling frequency increased, both fish and prey biomass declined, such that the ratio of fish to prey remained unchanged. Consequently, even at frequently trawled sites with low prey biomass, both plaice and dab maintained constant levels of stomach fullness and gut energy contents. However, dietary shifts in plaice towards energy-poor prey items were evident when prey species were analysed individually. This, together with a potential decrease in foraging efficiency due to low prey densities, was seen as the most plausible cause for the reduced body condition observed. Understanding the relationship between trawling, benthic impacts, fish foraging and resultant body condition is an important step in designing successful mitigation measures for future management strategies in bottom trawl fisheries. PMID:25621336

  13. Effects of bottom trawling on fish foraging and feeding

    PubMed Central

    Johnson, Andrew Frederick; Gorelli, Giulia; Jenkins, Stuart Rees; Hiddink, Jan Geert; Hinz, Hilmar

    2015-01-01

    The effects of bottom trawling on benthic invertebrates include reductions of biomass, diversity and body size. These changes may negatively affect prey availability for demersal fishes, potentially leading to reduced food intake, body condition and yield of fishes in chronically trawled areas. Here, the effect of trawling on the prey availability and diet of two commercially important flatfish species, plaice (Pleuronectes platessa) and dab (Limanda limanda), was investigated over a trawling intensity gradient in the Irish Sea. Previous work in this area has shown that trawling negatively affects the condition of plaice but not of dab. This study showed that reductions in local prey availability did not result in reduced feeding of fish. As trawling frequency increased, both fish and prey biomass declined, such that the ratio of fish to prey remained unchanged. Consequently, even at frequently trawled sites with low prey biomass, both plaice and dab maintained constant levels of stomach fullness and gut energy contents. However, dietary shifts in plaice towards energy-poor prey items were evident when prey species were analysed individually. This, together with a potential decrease in foraging efficiency due to low prey densities, was seen as the most plausible cause for the reduced body condition observed. Understanding the relationship between trawling, benthic impacts, fish foraging and resultant body condition is an important step in designing successful mitigation measures for future management strategies in bottom trawl fisheries. PMID:25621336

  14. Environmental health impacts of feeding crops to farmed fish.

    PubMed

    Fry, Jillian P; Love, David C; MacDonald, Graham K; West, Paul C; Engstrom, Peder M; Nachman, Keeve E; Lawrence, Robert S

    2016-05-01

    Half of the seafood consumed globally now comes from aquaculture, or farmed seafood. Aquaculture therefore plays an increasingly important role in the global food system, the environment, and human health. Traditionally, aquaculture feed has contained high levels of wild fish, which is unsustainable for ocean ecosystems as demand grows. The aquaculture industry is shifting to crop-based feed ingredients, such as soy, to replace wild fish as a feed source and allow for continued industry growth. This shift fundamentally links seafood production to terrestrial agriculture, and multidisciplinary research is needed to understand the ecological and environmental health implications. We provide basic estimates of the agricultural resource use associated with producing the top five crops used in commercial aquaculture feed. Aquaculture's environmental footprint may now include nutrient and pesticide runoff from industrial crop production, and depending on where and how feed crops are produced, could be indirectly linked to associated negative health outcomes. We summarize key environmental health research on health effects associated with exposure to air, water, and soil contaminated by industrial crop production. Our review also finds that changes in the nutritional content of farmed seafood products due to altered feed composition could impact human nutrition. Based on our literature reviews and estimates of resource use, we present a conceptual framework describing the potential links between increasing use of crop-based ingredients in aquaculture and human health. Additional data and geographic sourcing information for crop-based ingredients are needed to fully assess the environmental health implications of this trend. This is especially critical in the context of a food system that is using both aquatic and terrestrial resources at unsustainable rates. PMID:26970884

  15. Biorobotic adhesion in water using suction cups.

    PubMed

    Bandyopadhyay, Promode R; Hrubes, J Dana; Leinhos, Henry A

    2008-03-01

    Echeneid fish, limpets and octopi use suction cups for underwater adhesion. When echeneid fish use suckers to 'hitch a ride' on sharks (which have riblet-patterned skins), the apparent absence of any pump or plumbing may be an advantage over biorobotic suction cups. An intriguing question is: How do they achieve seemingly persistent leak-free contact at low energy cost over rough surfaces? The design features of their suckers are explored in a biorobotic context of adhesion in water over rough surfaces. We have carried out experiments to compare the release force and tenacity of man-made suction cups with those reported for limpets and echeneid fish. Applied tensile and shear release forces were monotonically increased until release. The effects of cup size and type, host surface roughness, curvature and liquid surface tension have been examined. The flow of water in the sharkskin-like host surface roughness has been characterized. The average tenacity is 5.28 N cm(-2) (sigma = 0.53 N cm(-2), N = 37) in the sub-ambient pressure range of 14.6-49.0 kPa, in man-made cups for monotonically increasing applied release force. The tenacity is lower for harmonically oscillating release forces. The dynamic structural interactions between the suction cup and the oscillating applied forcing are discussed. Inspired by the matching of sharkskin riblet topology in echeneid fish suckers, it was found that biorobotic sealed contact over rough surfaces is also feasible when the suction cup makes a negative copy of the rough host surface. However, for protracted, persistent contact, the negative topology would have to be maintained by active means. Energy has to be spent to maintain the negative host roughness topology to minute detail, and protracted hitch-riding on sharks for feeding may not be free for echeneid fish. Further work is needed on the mechanism and efficiency of the densely populated tiny actuators in the fish suckers that maintain leak-proof contact with minimal

  16. Fish oil replacement in current aquaculture feed: is cholesterol a hidden treasure for fish nutrition?

    PubMed

    Norambuena, Fernando; Lewis, Michael; Hamid, Noor Khalidah Abdul; Hermon, Karen; Donald, John A; Turchini, Giovanni M

    2013-01-01

    Teleost fish, as with all vertebrates, are capable of synthesizing cholesterol and as such have no dietary requirement for it. Thus, limited research has addressed the potential effects of dietary cholesterol in fish, even if fish meal and fish oil are increasingly replaced by vegetable alternatives in modern aquafeeds, resulting in progressively reduced dietary cholesterol content. The objective of this study was to determine if dietary cholesterol fortification in a vegetable oil-based diet can manifest any effects on growth and feed utilization performance in the salmonid fish, the rainbow trout. In addition, given a series of studies in mammals have shown that dietary cholesterol can directly affect the fatty acid metabolism, the apparent in vivo fatty acid metabolism of fish fed the experimental diets was assessed. Triplicate groups of juvenile fish were fed one of two identical vegetable oil-based diets, with additional cholesterol fortification (high cholesterol; H-Chol) or without (low cholesterol; L-Chol), for 12 weeks. No effects were observed on growth and feed efficiency, however, in fish fed H-Col no biosynthesis of cholesterol, and a remarkably decreased apparent in vivo fatty acid β-oxidation were recorded, whilst in L-Chol fed fish, cholesterol was abundantly biosynthesised and an increased apparent in vivo fatty acid β-oxidation was observed. Only minor effects were observed on the activity of stearyl-CoA desaturase, but a significant increase was observed for both the transcription rate in liver and the apparent in vivo activity of the fatty acid Δ-6 desaturase and elongase, with increasing dietary cholesterol. This study showed that the possible effects of reduced dietary cholesterol in current aquafeeds can be significant and warrant future investigations. PMID:24324720

  17. Fish Oil Replacement in Current Aquaculture Feed: Is Cholesterol a Hidden Treasure for Fish Nutrition?

    PubMed Central

    Norambuena, Fernando; Lewis, Michael; Hamid, Noor Khalidah Abdul; Hermon, Karen; Donald, John A.; Turchini, Giovanni M.

    2013-01-01

    Teleost fish, as with all vertebrates, are capable of synthesizing cholesterol and as such have no dietary requirement for it. Thus, limited research has addressed the potential effects of dietary cholesterol in fish, even if fish meal and fish oil are increasingly replaced by vegetable alternatives in modern aquafeeds, resulting in progressively reduced dietary cholesterol content. The objective of this study was to determine if dietary cholesterol fortification in a vegetable oil-based diet can manifest any effects on growth and feed utilization performance in the salmonid fish, the rainbow trout. In addition, given a series of studies in mammals have shown that dietary cholesterol can directly affect the fatty acid metabolism, the apparent in vivo fatty acid metabolism of fish fed the experimental diets was assessed. Triplicate groups of juvenile fish were fed one of two identical vegetable oil-based diets, with additional cholesterol fortification (high cholesterol; H-Chol) or without (low cholesterol; L-Chol), for 12 weeks. No effects were observed on growth and feed efficiency, however, in fish fed H-Col no biosynthesis of cholesterol, and a remarkably decreased apparent in vivo fatty acid β-oxidation were recorded, whilst in L-Chol fed fish, cholesterol was abundantly biosynthesised and an increased apparent in vivo fatty acid β-oxidation was observed. Only minor effects were observed on the activity of stearyl-CoA desaturase, but a significant increase was observed for both the transcription rate in liver and the apparent in vivo activity of the fatty acid Δ-6 desaturase and elongase, with increasing dietary cholesterol. This study showed that the possible effects of reduced dietary cholesterol in current aquafeeds can be significant and warrant future investigations. PMID:24324720

  18. Evaluation of an alternative to feeding whole frozen fish in belugas (Delphinapterus leucas).

    PubMed

    Mazzaro, Lisa M; Richmond, Julie P; Morgan, Jessica N; Kluever, Michaela E; Dunn, J Lawrence; Romano, Tracy A; Zinn, Steven A; Koutsos, Elizabeth A

    2011-01-01

    Feeding fish to captive piscivores can be challenging owing to cost, availability, variability in nutrient, and caloric composition, as well as handling and storage concerns. This trial evaluated the response of three belugas to being fed Fish Analog, an alternative to frozen fish. Body condition, gut transit time, serum chemistry and metabolic hormone analytes, immune function, and behavioral motivation were the dependent variables. Belugas (n=3) were fed various levels of Fish Analog (0-50%) over a 6-month period, and follow-up studies were conducted to further examine several dependent variables. When provided in gradually increasing amounts, belugas consumed the Fish Analog, with only minor fecal consistency changes and without behavioral responses indicative of gastric discomfort. Axillary girth and blubber thickness were positively correlated, and did not differ significantly with changes in the percentage of Fish Analog fed. Individual animal variation in initial passage time, some serum chemistry analytes, and immune function differences were noted following feeding of Fish Analog. Feeding Fish Analog reduced blood n9 fatty acids compared with captive belugas fed no Fish Analog. Feeding a DHA-enriched Fish Analog increased several n3 fatty acids, including eicosapentaenoic acid, but not DHA, compared with whales fed no Fish Analog or non-DHA-enriched Fish Analog. Fish Analog was shown to be a viable alternative to feeding fish at up to 50% of the dietary caloric density. PMID:21319209

  19. Associations among coral reef macroalgae influence feeding by herbivorous fishes

    NASA Astrophysics Data System (ADS)

    Loffler, Z.; Bellwood, D. R.; Hoey, A. S.

    2015-03-01

    Benthic macroalgae often occur in close association with other macroalgae, yet the implications of such associations on coral reefs are unclear. We selected three pairs of commonly associated macroalgae on inshore reefs of the Great Barrier Reef and exposed them, either independently or paired, to herbivore assemblages. Pairing the palatable alga Acanthophora with the calcified and chemically defended Galaxaura resulted in a 69 % reduction in the consumption of Acanthophora, but had no effect on the consumption of Galaxaura. The reduced consumption of Acanthophora was related to 53-85 % reductions in the feeding rates of two herbivorous fish species, Kyphosus vaigiensis and Siganus doliatus. Neither Acanthophora nor Sargassum were afforded protection when paired with the brown macroalga Turbinaria. Although limited to one of the three species pairings, such associations between algae may allow the ecological persistence of palatable species in the face of intense herbivory, enhancing macroalgal diversity on coral reefs.

  20. Effects of various feed supplements containing fish protein hydrolysate or fish processing by-products on the innate immune functions of juvenile coho salmon (oncorhynchus kisutch)

    USGS Publications Warehouse

    Murray, A.L.; Pascho, R.J.; Alcorn, S.W.; Fairgrieve, W.T.; Shearer, K.D.; Roley, D.

    2003-01-01

    Immunomodulators administered to fish in the diet have been shown in some cases to enhance innate immune defense mechanisms. Recent studies have suggested that polypeptide fractions found in fish protein hydrolysates may stimulate factors in fish important for disease resistance. For the current study, groups of coho salmon were reared on practical feeds that contained either fish meal (Control diet), fish meal supplemented with cooked fish by-products, or fish meal supplemented with hydrolyzed fish protein alone, or with hydrolyzed fish protein and processed fish bones. For each diet group, three replicate tanks of fish were fed the experimental diets for 6 weeks. Morphometric measurements, and serologic and cellular assays were used to evaluate the general health and immunocompetence of fish in the various feed groups. Whereas the experimental diets had no effect on the morphometric and cellular measurements, fish fed cooked by-products had increased leucocrit levels and lower hematocrit levels than fish from the other feed groups. Innate cellular responses were increased in all feed groups after feeding the four experimental diets compared with pre-feed results. Subgroups of fish from each diet group were also challenged with Vibrio anguillarum (ca. 7.71 ?? 105 bacteria ml-1) at 15??C by immersion. No differences were found in survival among the various feed groups.

  1. Feeding response of sport fish after electrical immobilization, chemical sedation, or both

    USGS Publications Warehouse

    Meinertz, Jeffery R.; Fredricks, Kim T.; Ambrose, Ryan D.; Jackan, Leanna M.; Wise, Jeremy K.

    2012-01-01

    Fishery managers frequently capture wild fish for a variety of fishery management activities. Though some activities can be accomplished without immobilizing the fish, others are accomplished more readily, humanely, and safely (for both the handler and the fish) when fish are immobilized by physical (e.g., electrical immobilization) or chemical sedation. A concern regarding the use of chemical sedatives is that chemical residues may remain in the fillet tissue after the fish recovers from sedation. If those residues are harmful to humans, there is some risk that a postsedated fish released to public waters may be caught and consumed by an angler. To characterize this risk, a series of four trials were conducted. Three trials assessed feeding activity after hatchery-reared fish were electrically immobilized, chemically sedated, or both, and one trial assessed the likelihood of an angler catching a wild fish that had been electrically immobilized and chemically sedated. Results from the first trial indicated that the feeding activity of laboratory habituated fish was variable among and within species after electrical immobilization, chemical sedation, or both. Results from the second trial indicated that the resumption of feeding activity was rapid after being mildly sedated for 45 min. Results from the third trial indicated that the feeding activity of outdoor, hatchery-reared fish was relatively aggressive after fish had been chemically sedated. Results from the fourth trial indicated that the probability of capturing wild fish in a more natural environment by angling after fish had been electrically immobilized and chemically sedated is not likely, i.e., in a group of five fish caught, 3 out of 100 times one would be a fish that had been sedated.

  2. Occurrence of Deoxynivalenol and Zearalenone in Commercial Fish Feed: An Initial Study

    PubMed Central

    Pietsch, Constanze; Kersten, Susanne; Burkhardt-Holm, Patricia; Valenta, Hana; Dänicke, Sven

    2013-01-01

    The control of mycotoxins is a global challenge not only in human consumption but also in nutrition of farm animals including aquatic species. Fusarium toxins, such as deoxynivalenol (DON) and zearalenone (ZEN), are common contaminants of animal feed but no study reported the occurrence of both mycotoxins in fish feed so far. Here, we report for the first time the occurrence of DON and ZEN in samples of commercial fish feed designed for nutrition of cyprinids collected from central Europe. A maximal DON concentration of 825 μg kg−1 feed was found in one feed whereas average values of 289 μg kg−1 feed were noted. ZEN was the more prevalent mycotoxin but the concentrations were lower showing an average level of 67.9 μg kg−1 feed. PMID:23325300

  3. Chemical contaminants in fish feeds used in federal salmonid hatcheries in the USA

    USGS Publications Warehouse

    Maule, A.G.; Gannam, A.L.; Davis, J.W.

    2007-01-01

    Recent studies have demonstrated that fish feeds contain significant concentrations of contaminants, many of which can bioaccumulate and bioconcentrate in fish. Organochlorine (OC) contaminants are present in the fish oils and fish meals used in feed manufacture, and some researchers speculate that all fish feeds contain measurable levels of some contaminants. To determine the concentration of contaminants in feeds used in US Fish and Wildlife Service's National Fish Hatcheries, we systematically collected samples of feed from 11 cold-water fish hatcheries. All samples (collected from October 2001 to October 2003) contained at least one polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF), polychlorinated biphenyl (PCB) congener, or dichlorodiphenyltrichloroethane (DDT) metabolite. Of the 55 samples in which they were analyzed 39 contained PCDDs, 24 contained PCDFs and 24 contained DDT or its metabolites. There were 10- to 150-fold differences in concentrations of total PCBs, PCDDs, PCDFs and DDT. Although PCBs were the most commonly detected contaminant in our study, concentrations (range: 0.07-10.46 ng g-1 wet weight) were low compared to those reported previously. In general, we also found lower levels of OCs than reported previously in fish feed. Perhaps most notable was the near absence of OC pesticides - except for DDT or its metabolites, and two samples containing hexachlorocyclohexane (HCH). While contaminant concentrations were generally low, the ecological impacts can not be determined without a measure of the bioaccumulation of these compounds in the fish and the fate of these compounds after the fish are released. ?? 2006 Elsevier Ltd. All rights reserved.

  4. Natural occurrence of emerging Fusarium mycotoxins in feed and fish from aquaculture.

    PubMed

    Tolosa, Josefa; Font, Guillermina; Mañes, Jordi; Ferrer, Emilia

    2014-12-24

    A new analytical method for the simultaneous determination of enniatins (ENs) and beauvericin (BEA) in fish feed and fish tissues by liquid chromatography coupled to mass spectrometry with linear ion trap (LC-MS/MS-LIT) was developed. Results showed that the developed method is precise and sensitive. The presence of emerging Fusarium mycotoxins, ENs and BEA, was determined in samples of aquaculture fish and feed for farmed fish, showing that all feed samples analyzed were contaminated with mycotoxins, with 100% coexistence. In aquacultured fish samples, the highest incidence was found in edible muscle and liver. As for the exposure assessment calculated, it was found that average consumer intake was lower than tolerable daily intake (TDI) values for other Fusarium mycotoxins. PMID:25432004

  5. Food wastes as fish feeds for polyculture of low-trophic-level fish: bioaccumulation and health risk assessments of heavy metals in the cultured fish.

    PubMed

    Cheng, Zhang; Lam, Cheung-Lung; Mo, Wing-Yin; Nie, Xiang-Ping; Choi, Wai-Ming; Man, Yu-Bon; Wong, Ming-Hung

    2016-04-01

    The major purpose of this study was to use different types of food wastes which serve as the major sources of protein to replace the fish meal used in fish feeds to produce quality fish. Two types of food waste-based feed pellets FW A (with cereals) and FW B (with cereals and meat products) and the commercial feed Jinfeng® were used to culture fingerlings of three low-trophic-level fish species: bighead carp, grass carp, and mud carp (in the ratio of 1:3:1) for 1 year period in the Sha Tau Kok Organic Farm in Hong Kong. Heavy metal concentrations in all of the fish species fed with food waste pellets and commercial pellets in Sha Tau Kok fish ponds were all below the local and international maximum permissible levels in food. Health risk assessments indicated that human consumption of the fish fed with food waste feed pellets was safe for the Hong Kong residents. The present results revealed that recycling of food waste for cultivating low-trophic-level fish (mainly herbivores and detritus feeders) is feasible, and at the same time will ease the disposal pressure of food waste, a common problem of densely populated cities like Hong Kong. PMID:27002811

  6. Red Light Stimulates Feeding Motivation in Fish but Does Not Improve Growth

    PubMed Central

    Bovi, Thais S.; de Freitas, Renato H. A.; da Silva, Danielle F.; Delicio, Helton C.; Barreto, Rodrigo Egydio

    2013-01-01

    Nile tilapia fish were individually reared under similar light levels for 8 weeks under five colored light spectra (maximum wavelength absorbance): white (full light spectrum), blue (∼452 nm), green (∼516 nm), yellow (∼520 nm) or red (∼628 nm). The effects of light on feeding, latency to begin feeding, growth and feed conversion were measured during the last 4 weeks of the study (i.e., after acclimation). We found that red light stimulates feeding, as in humans, most likely by affecting central control centers, but the extra feeding is not converted into growth. PMID:23516606

  7. Is nasogastric suction necessary in acute pancreatitis?

    PubMed Central

    Naeije, R; Salingret, E; Clumeck, N; De Troyer, A; Devis, G

    1978-01-01

    Fifty-eight patients with mild to moderately severe acute pancreatitis were randomly allocated to treatment with or without nasogastric suction (27 and 31 patients respectively). Intravenous fluids and pethidine hydrochloride were also given. The two groups were comparable clinically at the start of the study. There were no differences between the two groups in the mean duration of the following features: abdominal pain or tenderness; absence of bowel movements; raised serum amylase concentration; time to resumption of oral feeding; and days in hospital. Prolonged hyperamylasaemia (serum amylase greater than 0.33 mU/l) occurred in one patient in the suction group and in three patients in the non-suction group. A mild recurrence of abdominal pain after resumption of oral feeding occurred in three patients in the suction group and in two patients in the non-suction group. Two patients in the suction group developed overt consumption coagulopathy and two others pulmonary complications. No patient in the non-suction group had complications. The findings suggest that most patients with mild to moderately severe acute pancreatitis do not benefit from nasogastric suction. The procedure should be elective rather than mandatory in treating this condition. PMID:698650

  8. Levels of synthetic antioxidants (ethoxyquin, butylated hydroxytoluene and butylated hydroxyanisole) in fish feed and commercially farmed fish.

    PubMed

    Lundebye, A-K; Hove, H; Måge, A; Bohne, V J B; Hamre, K

    2010-12-01

    Several synthetic antioxidants are authorized for use as feed additives in the European Union. Ethoxyquin (EQ) and butylated hydroxytoluene (BHT) are generally added to fish meal and fish oil, respectively, to limit lipid oxidation. The study was conducted to examine the concentrations of EQ, BHT and butylated hydroxyanisole (BHA) in several commercially important species of farmed fish, namely Atlantic salmon, halibut and cod and rainbow trout, as well as concentrations in fish feed. The highest levels of BHT, EQ and BHA were found in farmed Atlantic salmon fillets, and were 7.60, 0.17 and 0.07 mg kg(-1), respectively. The lowest concentrations of the synthetic antioxidants found were in cod. The concentration of the oxidation product ethoxyquin dimer (EQDM) was more than ten-fold higher than the concentration of parent EQ in Atlantic salmon halibut and rainbow trout, whereas this dimer was not detected in cod fillets. The theoretical consumer exposure to the synthetic antioxidants EQ, BHA and BHT from the consumption of farmed fish was calculated. The contribution of EQ from a single portion (300 g) of skinned fillets of the different species of farmed fish would contribute at most 15% of the acceptable daily intake (ADI) for a 60 kg adult. The consumption of farmed fish would not contribute measurably to the intake of BHA; however, a 300 g portion of farmed Atlantic salmon would contribute up to 75% of the ADI for BHT. PMID:20931417

  9. Hiding and feeding in floating seaweed: Floating seaweed clumps as possible refuges or feeding grounds for fishes

    NASA Astrophysics Data System (ADS)

    Vandendriessche, Sofie; Messiaen, Marlies; O'Flynn, Sarah; Vincx, Magda; Degraer, Steven

    2007-02-01

    Floating seaweed is considered to be an important habitat for juvenile fishes due to the provision of food, shelter, a visual orientation point and passive transport. The importance of the presence of the highly dynamical seaweed clumps from the North Sea to juvenile neustonic fishes was investigated by analysing both neuston samples (without seaweed) and seaweed samples concerning fish community structure, and length-frequency distributions and feeding habits of five associated fish species. While the neustonic fish community was mainly seasonally structured, the seaweed-associated fish community was more complex: the response of the associated fish species to environmental variables was species specific and probably influenced by species interactions, resulting in a large multivariate distance between the samples dominated by Chelon labrosus and the samples dominated by Cyclopterus lumpus, Trachurus trachurus and Ciliata mustela. The results of the stomach analysis confirmed that C. lumpus is a weedpatch specialist that has a close spatial affinity with the seaweed and feeds intensively on the seaweed-associated invertebrate fauna. Similarly, C. mustela juveniles also fed on the seaweed fauna, but in a more opportunistic way. The shape of the size-frequency distribution suggested enhanced growth when associated with floating seaweed. Chelon labrosus and T. trachurus juveniles were generally large in seaweed samples, but large individuals were also encountered in the neuston. The proportion of associated invertebrate fauna in their diet was of minor importance, compared to the proportions in C. lumpus. Individuals of Syngnathus rostellatus mainly fed on planktonic invertebrates but had a discontinuous size-frequency distribution, suggesting that some of the syngnathids were carried with the seaweed upon detachment and stayed associated. Floating seaweeds can therefore be regarded as ephemeral habitats shared between several fish species (mainly juveniles) that use

  10. Evaluation of the in Vitro Anti-Atherogenic Properties of Lipid Fractions of Olive Pomace, Olive Pomace Enriched Fish Feed and Gilthead Sea Bream (Sparus aurata) Fed with Olive Pomace Enriched Fish Feed

    PubMed Central

    Nasopoulou, Constantina; Gogaki, Vassiliki; Stamatakis, Giorgos; Papaharisis, Leonidas; Demopoulos, Constantinos A.; Zabetakis, Ioannis

    2013-01-01

    Given the pivotal role of Platelet-Activating-Factor (PAF) in atherosclerosis and the cardio-protective role of PAF-inhibitors derived from olive pomace, the inclusion of olive pomace in fish feed has been studied for gilthead sea bream (Sparus aurata). The aim of the current research was to elucidate the anti-atherogenic properties of specific HPLC lipid fractions obtained from olive pomace, olive pomace enriched fish feed and fish fed with the olive pomace enriched fish feed, by evaluating their in vitro biological activity against washed rabbit platelets. This in vitro study underlines that olive pomace inclusion in fish feed improves the nutritional value of both fish feed and fish possibly by enriching the marine lipid profile of gilthead sea bream (Sparus aurata) with specific bioactive lipid compounds of plant origin. PMID:24084786

  11. Seasonal variation of assemblage and feeding guild structure of fish species in a boreal tidal basin

    NASA Astrophysics Data System (ADS)

    Kellnreitner, Florian; Pockberger, Moritz; Asmus, Harald

    2012-08-01

    Species composition, abundance, feeding relationships and guild structure of the fish assemblage in the Sylt-Rømø bight, a tidal basin in the northern Wadden Sea, were investigated to show seasonal differences and the importance of functional groups in this area. The tidal flats and in shallow subtidal areas were sampled using a beach seine and a bottom trawl net was used for deeper subtidal areas and tidal gullies. Species richness of fish was highest in summer where 26 species were caught, while the lowest richness was recorded in winter (17 species). Clear differences in species richness and abundance were found between shallow areas and deeper parts of the bight. Clupea harengus and Ammodytes tobianus were the most abundant species in deeper areas, while Pomatoschistus microps and Pomatoschistus minutus dominated shallower waters. Gut contents of 27 fish species were identified and the guild structure analyzed by UPGMA clustering of niche overlaps. Calanoid copepods (19.9%), Crangon crangon (18.2%) and mysid shrimps (8.4%) were the most abundant prey items of all fish species combined. Seven feeding guilds were present in the fall and winter, and eight and six in spring and summer, respectively. Fish feeding on calanoid copepods and C. crangon were present year round, whereas the occurrence of other guilds varied between seasons. Species composition of prey changed through seasons and, for some fish species, even the feeding mode itself varied with season. Most noticeable, 11 fish species changed guilds between seasons. We found a convergence in summer towards abundant prey items, whereas in winter diet overlap was lower. This is the first investigation of guild structure of almost all fish species present in a Wadden Sea area, and shows that consideration of seasonal differences is essential when determining feeding relationships of fish in temperate areas.

  12. Within-colony feeding selectivity by a corallivorous reef fish: foraging to maximize reward?

    PubMed Central

    Brooker, Rohan M; Jones, Geoffrey P; Munday, Philip L

    2013-01-01

    Foraging theory predicts that individuals should choose a prey that maximizes energy rewards relative to the energy expended to access, capture, and consume the prey. However, the relative roles of differences in the nutritive value of foods and costs associated with differences in prey accessibility are not always clear. Coral-feeding fishes are known to be highly selective feeders on particular coral genera or species and even different parts of individual coral colonies. The absence of strong correlations between the nutritional value of corals and prey preferences suggests other factors such as polyp accessibility may be important. Here, we investigated within-colony feeding selectivity by the corallivorous filefish, Oxymonacanthus longirostris, and if prey accessibility determines foraging patterns. After confirming that this fish primarily feeds on coral polyps, we examined whether fish show a preference for different parts of a common branching coral, Acropora nobilis, both in the field and in the laboratory experiments with simulated corals. We then experimentally tested whether nonuniform patterns of feeding on preferred coral species reflect structural differences between polyps. We found that O. longirostris exhibits nonuniform patterns of foraging in the field, selectively feeding midway along branches. On simulated corals, fish replicated this pattern when food accessibility was equal along the branch. However, when food access varied, fish consistently modified their foraging behavior, preferring to feed where food was most accessible. When foraging patterns were compared with coral morphology, fish preferred larger polyps and less skeletal protection. Our results highlight that patterns of interspecific and intraspecific selectivity can reflect coral morphology, with fish preferring corals or parts of coral colonies with structural characteristics that increase prey accessibility. PMID:24324862

  13. Algae in Fish Feed: Performances and Fatty Acid Metabolism in Juvenile Atlantic Salmon

    PubMed Central

    Norambuena, Fernando; Hermon, Karen; Skrzypczyk, Vanessa; Emery, James A.; Sharon, Yoni; Beard, Alastair; Turchini, Giovanni M.

    2015-01-01

    Algae are at the base of the aquatic food chain, producing the food resources that fish are adapted to consume. Previous studies have proven that the inclusion of small amounts (<10% of the diet) of algae in fish feed (aquafeed) resulted in positive effects in growth performance and feed utilisation efficiency. Marine algae have also been shown to possess functional activities, helping in the mediation of lipid metabolism, and therefore are increasingly studied in human and animal nutrition. The aim of this study was to assess the potentials of two commercially available algae derived products (dry algae meal), Verdemin (derived from Ulva ohnoi) and Rosamin (derived from diatom Entomoneis spp.) for their possible inclusion into diet of Atlantic Salmon (Salmo salar). Fish performances, feed efficiency, lipid metabolism and final product quality were assessed to investigated the potential of the two algae products (in isolation at two inclusion levels, 2.5% and 5%, or in combination), in experimental diets specifically formulated with low fish meal and fish oil content. The results indicate that inclusion of algae product Verdemin and Rosamin at level of 2.5 and 5.0% did not cause any major positive, nor negative, effect in Atlantic Salmon growth and feed efficiency. An increase in the omega-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) content in whole body of fish fed 5% Rosamin was observed. PMID:25875839

  14. Algae in fish feed: performances and fatty acid metabolism in juvenile Atlantic Salmon.

    PubMed

    Norambuena, Fernando; Hermon, Karen; Skrzypczyk, Vanessa; Emery, James A; Sharon, Yoni; Beard, Alastair; Turchini, Giovanni M

    2015-01-01

    Algae are at the base of the aquatic food chain, producing the food resources that fish are adapted to consume. Previous studies have proven that the inclusion of small amounts (<10% of the diet) of algae in fish feed (aquafeed) resulted in positive effects in growth performance and feed utilisation efficiency. Marine algae have also been shown to possess functional activities, helping in the mediation of lipid metabolism, and therefore are increasingly studied in human and animal nutrition. The aim of this study was to assess the potentials of two commercially available algae derived products (dry algae meal), Verdemin (derived from Ulva ohnoi) and Rosamin (derived from diatom Entomoneis spp.) for their possible inclusion into diet of Atlantic Salmon (Salmo salar). Fish performances, feed efficiency, lipid metabolism and final product quality were assessed to investigated the potential of the two algae products (in isolation at two inclusion levels, 2.5% and 5%, or in combination), in experimental diets specifically formulated with low fish meal and fish oil content. The results indicate that inclusion of algae product Verdemin and Rosamin at level of 2.5 and 5.0% did not cause any major positive, nor negative, effect in Atlantic Salmon growth and feed efficiency. An increase in the omega-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA) content in whole body of fish fed 5% Rosamin was observed. PMID:25875839

  15. Feeding behaviour of Black Sea bottom fishes: Did it change over time?

    NASA Astrophysics Data System (ADS)

    Bănaru, Daniela; Harmelin-Vivien, Mireille

    2009-11-01

    This study was designed to improve knowledge in feeding behaviour of the round goby ( Apollonia melanostomus (Pallas, 1814)), the red mullet ( Mullus barbatus ponticus Essipov, 1927), the whiting ( Merlangius merlangus (Linnaeus, 1758)), the flounder ( Platichthys flesus (Linnaeus, 1758)), the sole ( Solea solea (Linnaeus, 1758)), the turbot ( Psetta maeotica (Pallas, 1814)) and the starry sturgeon ( Acipenser stellatus Pallas, 1771) from the north-western Black Sea. Gut content coupled with stable isotope analysis allowed describing food web variations according to species, in two seasons and at two areas located seawards the Danube River. Present results showed that most fishes have likely changed their feeding behaviour compared to past studies from the same area. Trophic niches were reduced and dietary overlap was common, as different fish species consumed the same dominant prey types. Fishes probably adapted their feeding behaviour to the increasingly low biodiversity of the Black Sea communities.

  16. Feeding ecology of some fish species occurring in artisanal fishery of Socotra Island (Yemen).

    PubMed

    Hassan Ali', Mohammed Kaed; Belluscio, Andrea; Ventura, Daniele; Ardizzone, Giandomenico

    2016-04-30

    The demersal species Lethrinus borbonicus, Lethrinus mahsena, Lethrinus microdon, Lethrinus nebulosus, Lutjanus bohar, Lutjanus gibbus, Lutjanus kasmira, Epinephelus fasciatus, Epinephelus stoliczkae, Carangoides gymnostethus and Euthynnus affinis are important coastal fishes species of the northern coast of Socotra (Yemen), exploited by local fishery. The biology and feeding ecology of these species are poorly known in the area. A total of 1239 specimens were sampled from the main fishing landing site of the island (Hadibo). Total length and weight were measured, stomach contents were analyzed, diet overlap, Fulton's Condition index, and trophic levels were estimated. C. gymnostethus, L. microdon and L. kasmira occupied the highest position (T=4.50), L. nebulosus occupied the lower one (TL=3.41). The role of the increasing abundance of small pelagic fish in the diet of many species after the upwelling event is evident, but also different feeding strategies are reported, according to fish ecology. PMID:26880127

  17. Are kissing gourami specialized for substrate-feeding? Prey capture kinematics of Helostoma temminckii and other anabantoid fishes.

    PubMed

    Ferry, Lara A; Konow, Nicolai; Gibb, Alice C

    2012-11-01

    Helostoma temminckii are known for a "kissing" behavior, which is often used in intraspecific interactions, and an unusual cranial morphology that is characterized by an intramandibular joint (IMJ). The IMJ is located within the lower jaw and aids in generating the eponymous kissing movement. In other teleost linages the IMJ is associated with the adoption of a substrate-grazing foraging habit. However, because of anatomical modifications of the gill-rakers, Helostoma has been considered a midwater filter-feeding species. We offered midwater, benthic, and attached food to Helostoma, Betta, and two "true" osphronemid gouramis, to ask: (1) how do food capture kinematics differ in different foraging contexts; and (2) are Helostoma feeding kinematics distinct when compared with closely related anabantoids that lack an IMJ? For all anabantoid species except Helostoma, benthic prey were captured using a greater contribution of effective suction relative to midwater prey, though Helostoma was rarely willing to feed in the midwater. Helostoma individuals produced relatively less suction than other species regardless of the food type. Helostoma produced a much larger gape and more premaxillary protrusion than other species, but also took longer to do so. We suggest that the jaw morphology of Helostoma facilitates an extremely large mouth-gape to enhance substrate-scraping. The large amplitude mouth-opening that characterizes substrate-feeding may represent a functional trade-off, whereby the enhanced ability to procure food from the substrate is accompanied by a concomitant reduction in the ability to produce suction. PMID:22952136

  18. Food and feeding of fish in Hartwell Reservoir tailwater, Georgia-South Carolina

    USGS Publications Warehouse

    Barwick, D. Hugh; Hudson, Patrick L.

    1985-01-01

    Food of silver redhorse (Moxostoma anisurum), redbreast sunfish (Lepomis auritus), green sunfish (L. cyanellus), and bluegills (L. macrochirus) was examined to determine whether or not these fish in the Hartwell Reservoir tailwater (Savannah River, Georgia-South Carolina) ate organisms entrained from the reservoir or displaced from the tailwater during water releases associated with the production of hydropower. These fish fed primarily on aquatic insects, crayfish, and terrestrial organisms originating from the tailwater. Major periods of feeding occurred during nongeneration.

  19. Use of a gyroscope/accelerometer data logger to identify alternative feeding behaviours in fish.

    PubMed

    Kawabata, Yuuki; Noda, Takuji; Nakashima, Yuuki; Nanami, Atsushi; Sato, Taku; Takebe, Takayuki; Mitamura, Hiromichi; Arai, Nobuaki; Yamaguchi, Tomofumi; Soyano, Kiyoshi

    2014-09-15

    We examined whether we could identify the feeding behaviours of the trophic generalist fish Epinephelus ongus on different prey types (crabs and fish) using a data logger that incorporated a three-axis gyroscope and a three-axis accelerometer. Feeding behaviours and other burst behaviours, including escape responses, intraspecific interactions and routine movements, were recorded from six E. ongus individuals using data loggers sampling at 200 Hz, and were validated by simultaneously recorded video images. For each data-logger record, we extracted 5 s of data when any of the three-axis accelerations exceeded absolute 2.0 g, to capture all feeding behaviours and other burst behaviours. Each feeding behaviour was then identified using a combination of parameters that were derived from the extracted data. Using decision trees with the parameters, high true identification rates (87.5% for both feeding behaviours) with low false identification rates (5% for crab-eating and 6.3% for fish-eating) were achieved for both feeding behaviours. PMID:25013109

  20. Social interactions can affect feeding behaviour of fish in tanks

    NASA Astrophysics Data System (ADS)

    Kooijman, S. A. L. M.

    2009-08-01

    Fish from the same clutch of eggs, so of the same age and family, can differ substantially in size after some time in a tank as result of social interactions. On the basis of computer simulation studies I here demonstrate that it is possible to mimic this empirical observation using the rules of the standard Dynamic Energy Budget (DEB) model, supplemented with a simple stochastic module for interaction between individuals that have identical parameters. The remarkable result is that length-at-age of two individuals in a tank where the number of food particles is kept constant closely follows von Bertalanffy growth curves with very different parameters, while in reality the individuals have identical parameters. The empirical observation demonstrates that fish are close to the supply end of the supply-demand spectrum and that age-based models for growth don't apply to supply systems. The significance of the result is discussed.

  1. FISH MEAL REPLACEMENT; EFFECT OF ALTERNATE FEED INGREDIENTS AND NUTRIENT DENSITY ON GROWTH EFFICIENCY OF RAINBOW TROUT ONCORHYNCHUS MYKISS".

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Development of plant-based, fish-meal free, aquaculture feeds will provide economic, environmental, and health benefits to several sectors of society. Fish growth and feed costs need to be competitive with that observed using current formulations. New ingredients that have not been routinely fed t...

  2. Potential of thraustochytrids to partially replace fish oil in Atlantic salmon feeds.

    PubMed

    Carter, C G; Bransden, M P; Lewis, T E; Nichols, P D

    2003-01-01

    The replacement of fish oil with a dried product made from thraustochytrid culture, a marine microorganism, in canola-oil-based diets for Atlantic salmon was investigated. Salmon (37 g) were fed for 51 days on diets containing only canola oil, canola oil and fish oil, or canola oil and the thraustochytrid. There were no significant differences in final weight (106.1 +/- 1.1 g), weight gain (69.6 +/- 1.1 g), feed consumption (16.5 +/- 0.2 mg dry matter g(-1) d(-1)), feed efficiency ratio (1.15 +/- 0.03 g (g-1)), or productive protein value (51.2% +/- 1.7%) between the diets. Nor were there any significant differences in whole-body chemical composition, organ somatic indices, or measures of immune function. However, following transfer to seawater and 2 challenges with Vibrio anguillarum, cumulative mortality was significantly lower in fish fed some fish oil than in those fed the 2 diets containing no fish oil. In conclusion, the thraustochytrid had no detrimental effects on the performance of salmon but, at the current inclusion of 10%, failed to confer the same effect as fish oil under challenging conditions. PMID:14730431

  3. Trophic transfer of sediment-associated polychlorinated biphenyls from meiobenthos to bottom-feeding fish

    SciTech Connect

    DiPinto, L.M.; Coull, B.C.

    1997-12-01

    Experiments were conducted to examine the dynamics of the sediment-associated polychlorinated biphenyl (PCB) using a benthic-based trophic transfer model (sediments to benthic copepods to juvenile fish). Field-collected benthic copepods were exposed to sublethal levels of PCB in sediments for 96 h. Accumulation of PCB was measured in the copepods, and these contaminated copepods were fed to the juvenile fish predator Leiostomus xanthurus in uncontaminated sediments. After gut clearance, whole fish were homogenized and examined for PCB accumulation. Similar experiments with L. xanthurus in which meals of uncontaminated copepods were fed in PCB-contaminated sediments were conducted to determine the relative roles of contaminated sediments and contaminated copepod prey ingestion to PCB transfer. Total PCB transfer as well as PCB congener group contributions were examined. A total of 30 congeners were grouped according to log K{sub ow} increments and according to chlorine homologue groups. Copepods exposed to PCB-contaminated sediments to 90 {micro}g/g accumulated PCBs to 326 {micro}g/g dry weight. Accumulation of PCB in fish feeding in contaminated sediments was five times higher than that in fish feeding on contaminated prey in uncontaminated sediments (p = 0.0498). In terms of congener patterns, log K{sub ow} grouping provided clearer discrimination between groups. Congener patterns were similar in PCB stock solution, sediments, and copepods and were different in the two fish treatments. K{sub ow} group relative accumulation patterns in fish were mixed. The chlorine homologue groups revealed that the fish preferentially accumulated the tetrachlorinated congeners relative to copepods and sediments.

  4. Detection of artificial water flows by the lateral line system of a benthic feeding cichlid fish.

    PubMed

    Schwalbe, Margot A B; Sevey, Benjamin J; Webb, Jacqueline F

    2016-04-01

    The mechanosensory lateral line system of fishes detects water motions within a few body lengths of the source. Several types of artificial stimuli have been used to probe lateral line function in the laboratory, but few studies have investigated the role of flow sensing in benthic feeding teleosts. In this study, we used artificial flows emerging from a sandy substrate to assess the contribution of flow sensing to prey detection in the peacock cichlid, Aulonocara stuartgranti, which feeds on benthic invertebrates in Lake Malawi. Using a positive reinforcement protocol, we trained fish to respond to flows lacking the visual and chemical cues generated by tethered prey in prior studies with A. stuartgranti Fish successfully responded to artificial flows at all five rates presented (characterized using digital particle image velocimetry), and showed a range of flow-sensing behaviors, including an unconditioned bite response. Immediately after lateral line inactivation, fish rarely responded to flows and the loss of vital fluorescent staining of hair cells (with 4-di-2-ASP) verified lateral line inactivation. Within 2 days post-treatment, some aspects of flow-sensing behavior returned and after 7 days, flow-sensing behavior and hair cell fluorescence both returned to pre-treatment levels, which is consistent with the reported timing of hair cell regeneration in other vertebrates. The presentation of ecologically relevant water flows to assess flow-sensing behaviors and the use of a positive reinforcement protocol are methods that present new opportunities to study the role of flow sensing in the feeding ecology of benthic feeding fishes. PMID:27030780

  5. How to capture fish in a school? Effect of successive predator attacks on seabird feeding success.

    PubMed

    Thiebault, Andréa; Semeria, Magali; Lett, Christophe; Tremblay, Yann

    2016-01-01

    Prey aggregations, such as fish schools, attract numerous predators. This typically leads to the formation of multispecific groups of predators. These aggregations can be seen both as a place of increased competition and as a place of possible facilitation between predators. Consequently, the functional role of such predator-prey aggregation is uncertain, and its effect on individual feeding success is virtually unknown. Using underwater film footage of different predators feeding on fish schools during the sardine run in South Africa, we directly measured the in situ feeding success of individual Cape gannets Morus capensis in different foraging situations. We determined the types of Cape gannet attacks (direct plunge dive or plunge dive followed by underwater pursuit) and we measured the occurrences and timing of attacks from the different species (mostly Cape gannets and long-beaked common dolphins Delphinus capensis). We also estimated the size of the targeted fish schools. These observations were complemented with a simulation model to evaluate the cumulative effect of successive predator attacks on the prey aggregation structure. The probability to capture a fish in one feeding attempt by Cape gannets averaged 0·28. It was lower when gannets engaged in underwater prey pursuit after the plunge compared to direct plunge (0·13 vs. 0·36). We found no effect of the number of prey on gannets' feeding success. However, the timing and frequency of attacks influenced strongly and positively the feeding success of individuals. The probability to capture a fish was the lowest (0·16) when no attack occurred in the few seconds (1-15 s) prior to a dive and the highest (˜0·4, i.e. more than twice) when one or two attacks occurred during this time window. The simulation model showed that a prey aggregation disorganized just after an attack and that the maximum of disturbance was obtained a few seconds after the initiation of the successive attacks. Our study suggests

  6. Food Selectivity and Diet Switch Can Explain the Slow Feeding of Herbivorous Coral-Reef Fishes during the Morning

    PubMed Central

    Khait, Ruth; Obolski, Uri; Hadany, Lilach; Genin, Amatzia

    2013-01-01

    Most herbivorous coral-reef fishes feed slower in the morning than in the afternoon. Given the typical scarcity of algae in coral reefs, this behavior seems maladaptive. Here we suggest that the fishes' slow feeding during the morning is an outcome of highly selective feeding on scarcely found green algae. The rarity of the food requires longer search time and extended swimming tracks, resulting in lower bite rates. According to our findings by noon the fish seem to stop their search and switch to indiscriminative consumption of benthic algae, resulting in apparent higher feeding rates. The abundance of the rare preferable algae gradually declines from morning to noon and seems to reach its lowest levels around the switch time. Using in situ experiments we found that the feeding pattern is flexible, with the fish exhibiting fast feeding rates when presented with ample supply of preferable algae, regardless of the time of day. Analyses of the fish's esophagus content corroborated our conclusion that their feeding was highly selective in the morning and non-selective in the afternoon. Modeling of the fishes' behavior predicted that the fish should perform a diel diet shift when the preferred food is relatively rare, a situation common in most coral reefs found in a warm, oligotrophic ocean. PMID:24358178

  7. Growth and Feed Efficiency of Juvenile Channel Catfish Reared at Different Water Temperatures and Fed Diets Containing Various Levels of Fish Meal

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channel catfish Ictalurus punctatus do not feed well at low temperatures. It is thought that a diet containing fish meal may enhance feed palatability at low temperatures since fish meal is highly palatable to the fish. There is a lack of information on effects of fish meal levels on growth perfor...

  8. A trait-based approach reveals the feeding selectivity of a small endangered Mediterranean fish.

    PubMed

    Rodríguez-Lozano, Pablo; Verkaik, Iraima; Maceda-Veiga, Alberto; Monroy, Mario; de Sostoa, Adolf; Rieradevall, Maria; Prat, Narcís

    2016-05-01

    Functional traits are growing in popularity in modern ecology, but feeding studies remain primarily rooted in a taxonomic-based perspective. However, consumers do not have any reason to select their prey using a taxonomic criterion, and prey assemblages are variable in space and time, which makes taxon-based studies assemblage-specific. To illustrate the benefits of the trait-based approach to assessing food choice, we studied the feeding ecology of the endangered freshwater fish Barbus meridionalis. We hypothesized that B. meridionalis is a selective predator which food choice depends on several prey morphological and behavioral traits, and thus, its top-down pressure may lead to changes in the functional composition of in-stream macroinvertebrate communities. Feeding selectivity was inferred by comparing taxonomic and functional composition (13 traits) between ingested and free-living potential prey using the Jacob's electivity index. Our results showed that the fish diet was influenced by 10 of the 13 traits tested. Barbus meridionalis preferred prey with a potential size of 5-10 mm, with a medium-high drift tendency, and that drift during daylight. Potential prey with no body flexibility, conical shape, concealment traits (presence of nets and/or cases, or patterned coloration), and high aggregation tendency had a low predation risk. Similarly, surface swimmers and interstitial taxa were low vulnerable to predation. Feeding selectivity altered the functional composition of the macroinvertebrate communities. Fish absence favored taxa with weak aggregation tendency, weak flexibility, and a relatively large size (10-20 mm of potential size). Besides, predatory invertebrates may increase in fish absence. In conclusion, our study shows that the incorporation of the trait-based approach in diet studies is a promising avenue to improve our mechanistic understanding of predator-prey interactions and to help predict the ecological outcomes of predator invasions and

  9. Evolution of levers and linkages in the feeding mechanisms of fishes.

    PubMed

    Westneat, Mark W

    2004-11-01

    The evolution of feeding mechanisms in the ray-finned fishes (Actinopterygii) is a compelling example of transformation in a musculoskeletal complex involving multiple skeletal elements and numerous muscles that power skull motion. Biomechanical models of jaw force and skull kinetics aid our understanding of these complex systems and enable broad comparison of feeding mechanics across taxa. Mechanical models characterize how muscles move skeletal elements by pulling bones around points of rotation in lever mechanisms, or by transmitting force through skeletal elements connected in a linkage. Previous work has focused on the feeding biomechanics of several lineages of fishes, but a broader survey of skull function in the context of quantitative models has not been attempted. This study begins such a survey by examining the diversity of mechanical design of the oral jaws in 35 species of ray-finned fishes with three main objectives: (1) analyze lower jaw lever models in a broad phylogenetic range of taxa, (2) identify the origin and evolutionary patterns of change in the linkage systems that power maxillary rotation and upper jaw protrusion, and (3) analyze patterns of change in feeding design in the context of actinopterygian phylogeny. The mandibular lever is present in virtually all actinopterygians, and the diversity in lower jaw closing force transmission capacity, with mechanical advantage ranging from 0.04 to 0.68, has important functional consequences. A four-bar linkage for maxillary rotation arose in the Amiiformes and persists in various forms in many teleost species. Novel mechanisms for upper jaw protrusion based on this linkage for maxillary rotation have evolved independently at least five times in teleosts. The widespread anterior jaws linkage for jaw protrusion in percomorph fishes arose initially in Zeiformes and subsequently radiated into a wide range of premaxillary protrusion capabilities. PMID:21676723

  10. Feeding characteristics reveal functional distinctions among browsing herbivorous fishes on coral reefs

    NASA Astrophysics Data System (ADS)

    Streit, Robert P.; Hoey, Andrew S.; Bellwood, David R.

    2015-12-01

    The removal of macroalgal biomass by fishes is a key process on coral reefs. Numerous studies have identified the fish species responsible for removing mature macroalgae, and have identified how this varies spatially, temporally, and among different algal types. None, however, have considered the behavioural and morphological traits of the browsing fishes and how this may influence the removal of macroalgal material. Using video observations of fish feeding on the brown macroalga Sargassum polycystum, we quantified the feeding behaviour and morphology of the four dominant browsing species on the Great Barrier Reef ( Kyphosus vaigiensis, Naso unicornis, Siganus canaliculatus, and Siganus doliatus). The greatest distinction between species was the algal material they targeted. K. vaigiensis and N. unicornis bit on the entire macroalgal thallus in approximately 90 % of bites. In contrast, Si. canaliculatus and Si. doliatus avoided biting the stalks, with 80-98 % of bites being on the macroalgal leaves only. This distinctive grouping into `entire thallus-biters' versus `leaf-biters' was not supported by size-standardized measures of biting morphology. Rather, species-specific adult body sizes, tooth shape, and feeding behaviour appear to underpin this functional distinction, with adults of the two larger fish species ( N. unicornis and K. vaigiensis) eating the entire macroalgal thallus, while the two smaller species ( Si. canaliculatus and Si. doliatus) bite only leaves. These findings caution against assumed homogeneity within this, and potentially other, functional groups on coral reefs. As functional redundancy within the macroalgal browsers is limited, the smaller `leaf-biting' species are unlikely to be able to compensate functionally for the loss of larger `entire thallus-biting' species.

  11. Tropical agricultural residues and their potential uses in fish feeds: the Costa Rican situation.

    PubMed

    Ulloa, J B; van Weerd, J H; Huisman, E A; Verreth, J A J

    2004-01-01

    In Costa Rica as many other tropical countries, the disposal problem of agricultural wastes is widely recognized but efforts to find solutions are not equal for different sectors. This study describes the situation of major agricultural residues in Costa Rica, identifying the activities with higher amounts produced and, the potential use of these residues in fish feeds. In Costa Rica, during the 1993-1994 production season, major agricultural sectors (crop and livestock) generated a total amount of 3.15-3.25 million MT of residues (classified in by-products: used residues and wastes: not used residues). Some residues are treated to turn them into valuable items or to diminish their polluting effects (e.g., the so-called by-products). About 1.56-1.63 million MT of by-products were used for different purposes (e.g. fertilization, animal feeding, fuel, substrates in greenhouses). However, the remainder (1.59-1.62 million MT) was discharged into environment causing pollution. About 1.07-1.2 million MT wastes came from major crop systems (banana, coffee, sugarcane and oil palm) whereas the remainder came from animal production systems (porcine and poultry production, slaughtering). These data are further compared to residues estimates for the 2001-2002 production season coming from the biggest crops activities. Unfortunately, most of the studied wastes contain high levels of moisture and low levels of protein, and also contain variable amounts of antinutritional factors (e.g., polyphenols, tannins, caffeine), high fibre levels and some toxic substances and pesticides. All these reasons may limit the use of these agricultural wastes for animal feeding, especially in fish feeds. The potential use of the major vegetable and animal residues in fish feeds is discussed based on their nutritional composition, on their amount available over the year and on their pollution risks. Other constraints to use these wastes in fish feeds are the extra costs of drying and, in most cases

  12. Feeding ecology of elasmobranch fishes in coastal waters of the Colombian Eastern Tropical Pacific

    PubMed Central

    Navia, Andrés F; Mejía-Falla, Paola A; Giraldo, Alan

    2007-01-01

    Background Stomach contents of 131 specimens of five elasmobranch species (Mustelus lunulatus, Dasyatis longa, Rhinobatos leucorhynchus, Raja velezi and Zapteryx xyster) caught in the central fishing zone in the Pacific Ocean of Colombia were counted and weighed to describe feeding habits and dietary overlaps. Results Twenty-one prey items belonging to four major groups (stomatopods, decapods, mollusks and fish) were identified. Decapod crustaceans were the most abundant prey found in stomachs. The mantis shrimp Squilla panamensis was the main prey item in the diet of M. lunulatus; tiger shrimp Trachypenaeus sp. was the main prey item in the diet of Rhinobatos leucorhynchus and Raja velezi, and Penaeidae shrimp were the main prey items in the diet of Z. xyster. Furthermore, fish were important in the diet of Raja velezi, Z. xyster and D. longa. The greatest diet breadth corresponded to Z. xyster whereas M. lunulatus was the most specialized predator. Finally, four significant diet overlaps between the five species were found, attributable mainly to Squillidae, Penaeidae and Fish. Conclusion Shrimps (Penaeidae and stomatopods) and benthic fishes were the most important food types in the diet of the elasmobranch species studied. Diet breadth and overlap were relatively low. Determination of food resource partitioning among the batoid species studied was not possible. However, we identified partitions in other niche axes (time of feeding activity and habitat utilization). It is possible to assume that diffuse competition could be exceeding the biunivocal competition among the studied species. Therefore, this assemblage would have a strong tendency to trophic guild formation. PMID:17877796

  13. Monitoring escape and feeding behaviours of cruiser fish by inertial and magnetic sensors.

    PubMed

    Noda, Takuji; Kawabata, Yuuki; Arai, Nobuaki; Mitamura, Hiromichi; Watanabe, Shun

    2013-01-01

    A method was developed and applied for monitoring two types of fast-start locomotion (feeding and escape) of a cruiser fish, Japanese amberjacks Seriola quinqueradiata. A data logger, which incorporated a 3-axis gyroscope, a 3-axis accelerometer and a 3-axis magnetometer, was attached to the five fish. The escape, feeding and routine movements of the fish, which were triggered in tank experiments, were then recorded by the data logger and video cameras. The locomotor variables, calculated based on the high resolution measurements by the data logger (500 Hz), were investigated to accurately detect and classify the types of fast-track behaviour. The results show that fast-start locomotion can be detected with a high precision (0.97) and recall rate (0.96) from the routine movements. Two types of fast-start movements were classified with high accuracy (0.84). Accuracy was greater if the data were obtained from the data logger, which combined an accelerometer, a gyroscope and a magnetometer, than if only an accelerometer (0.80) or a gyroscope (0.66) was used. PMID:24236126

  14. Phosphorus Loadings Associated with a Park Tourist Attraction: Limnological Consequences of Feeding the Fish

    NASA Astrophysics Data System (ADS)

    Turner, Andrew M.; Ruhl, Nathan

    2007-04-01

    The Linesville spillway of Pymatuning State Park is one of the most visited tourist attractions in Pennsylvania, USA, averaging more than 450,000 visitors · year-1. Carp ( Cyprinus carpio Linnaeus) and waterfowl congregate at the spillway where they are fed bread and other foods by park visitors. We hypothesized that the “breadthrowers” constitute a significant nutrient vector to the upper portion of Pymatuning Reservoir. In the summer of 2002, we estimated phosphorus loadings attributable to breadthrowers, and compared these values to background loadings from Linesville Creek, a major tributary to the upper reservoir. Items fed to fish included bread, donuts, bagels, canned corn, popcorn, corn chips, hot dogs, birthday cakes, and dog food. Phosphorus loading associated with park visitors feeding fish was estimated to be 3233 g day-1, and estimated P export from the Linesville Creek watershed was 2235 g·day-1. P loading attributable to breadthrowers exceeded that of the entire Linesville Creek watershed on 33 of the 35 days of study, with only a heavy rainfall event triggering watershed exports that exceeded spillway contributions. Averaged across 5 weeks, breadthrowers contributed 1.45-fold more P to Pymatuning Reservoir than the Linesville Creek watershed. If Linesville Creek P exports are extrapolated to the entire Sanctuary Lake watershed, spillway contributions of P added 48% to the non-point source watershed P entering the lake. Park visitors feeding fish at the Linesville Spillway are a significant source of nutrients entering Sanctuary Lake.

  15. Changes in the trophic status of fish feeding guilds in response to flow modification

    NASA Astrophysics Data System (ADS)

    Delong, M. D.; Thoms, M. C.

    2016-03-01

    Rivers are among the most extensively modified ecosystems globally. Identifying linkages between critical drivers of change and ecological response is challenging because of the myriad of ways rivers are modified. This study examines longer-term relationships (>70 years) between the trophic status of fish and historical flow changes in rivers of the Mississippi Basin. The flow regime of each river is regulated but differs in terms of character of hydrological modification. Tissue samples from specimens obtained from museum collections were used for determination of carbon and nitrogen stable isotope ratios. Questions asked were as follows: (1) Are there differences in stable isotope ratios of fish feeding guilds prior to and following hydrological modification? (2) What hydrological attributes are associated with isotopic changes? And (3) are corresponding changes in stable isotope ratios and hydrology identifiable across different spatial scales? Significant and sustained changes in stable isotope ratios of fish feeding guilds occurred immediately following flow regulation in all rivers. These changes were not associated with human-induced biogeochemical alterations. The subsequent response was complex because (1) different guilds exhibited pronounced shifts in isotopic ratios, (2) hydrological modification differed between rivers, and (3) differences in stable isotopic ratios varied between spatial scales.

  16. "Who's been feeding in my bed?" Benthivorous fish affect fluvial sediment transport - fact or fairy tale?

    NASA Astrophysics Data System (ADS)

    Rice, Stephen; Pledger, Andrew; Smith, James; Toone, Julia

    2016-04-01

    Many species of fish are benthivorous - they forage for food in the river bed - and their foraging disturbs, displaces and sorts bed materials with implications for fluvial sediment transport. Flume experiments have confirmed that benthic foraging by Barbel (Barbus barbus (L.)) and Chub (Squalius cephalus (L.)) modifies the structure and topography of water-worked gravels, thereby increasing particle entrainment probabilities and the quantity of sediment mobilised during experimental high flows. Field experiments and observations have demonstrated the impact of foraging on patch-scale bed disturbance, gravel structure, grain displacements and grain-size sorting. Initial ex-situ experiments support the suggestion that in low gradient rivers, shoals of fish like Bream (Abramis brama (L.)) entrain fine bed sediments, adding a biotic surcharge to the suspended sediment flux and modifying bed topography. These results underpin a novel proposal: that there is an aggregate, cumulative effect of benthic foraging on fluvial sediment transport at larger scales, including at scales where the contribution to sediment movement and river channel behaviour generates management concerns. Evaluating this proposal is a long-term goal, which is based on two intermediate objectives: to develop deeper mechanistic understanding of foraging impacts and to establish the spatial and temporal extent of geomorphologically significant feeding behaviours in river systems. The latter is crucial because field data are currently limited to a single reach on one UK river. It is reasonable to hypothesise that foraging impacts are spatially and temporally widespread because obligate and opportunistic benthic feeding is common and fish feed throughout their life. However, the effectiveness of foraging as a geomorphological process is likely to vary with factors including substrate size, fish community composition, food availability, water temperature, river flows and seasonal changes in fish

  17. Diet and feeding strategies of mesopelagic fishes in the western Mediterranean

    NASA Astrophysics Data System (ADS)

    Bernal, Ainhoa; Olivar, M. Pilar; Maynou, Francesc; Fernández de Puelles, M. Luz

    2015-06-01

    Myctophids, gonostomatids and sternoptychids are the most abundant teleosteans worldwide and constitute an important assemblage of the mesopelagic ecosystem, functioning as vehicles of energy and matter through trophic webs. This study concentrates on the trophic ecology of the most abundant mesopelagic fishes of the western Mediterranean (WM) based on stomach content analysis. The myctophids (in this study: Benthosema glaciale, Ceratoscopelus maderensis, Lobianchia dofleini, Myctophum punctatum, Hygophum benoiti, Hygophum hygomii, Lampanyctus crocodilus, Lampanyctus pusillus and Notoscopelus elongatus) perform extensive diel migrations across the water column, between the surface to as deep as 1000 m, interacting with plankton and micronekton at multiple depths, and generally feeding in the epipelagic layers at night. In contrast, the gonostomatids Cyclothone braueri, Cyclothone pygmaea, and the sternoptychid Argyropelecus hemigymnus remain below epipelagic layers, feeding at different times throughout the day and night. The diet composition, trophic niche breadth and prey selectivity of 11 of these fish species were determined for juvenile and adult individuals from two surveys performed in December 2009 and July 2010 in the western Mediterranean Sea. The number of prey items varied among species, e.g. Myctophum punctatum was the species with the highest feeding intensity, reaching ca. 700 prey items in a stomach, whereas the mean number of prey in Cyclothone braueri was low (usually 1 or 2 prey per stomach). A dietary shift towards larger prey was evident from juveniles to the largest and oldest adult individuals, despite trophic niche breadths did not increase with body length for any of these mesopelagic species. The diets of the small gonostomatids, sternoptychid and early juveniles of myctophids were dominated by non-calanoid copepods, ostracods, and other small zooplankton, whereas medium-sized myctophids, e.g. L. dofleini or H. benoiti, preyed mainly on

  18. Phytoremediation of aquaculture wastewater for water recycling and production of fish feed.

    PubMed

    Ghaly, A E; Kamal, M; Mahmoud, N S

    2005-01-01

    Five plants were examined for their ability to remove nutrients from aquaculture wastewater and suitability as fish feed: alfalfa, white clover, oat, fall rye, barley. The seeds were first germinated in water in a hydroponic system, and the plants were fed wastewater from Tilapia production facility. Clover and alfalfa seeds were infected with fungus shortly after germination, and their roots were completely destroyed by day 14. Oat, rye and barley had the fastest growth and showed greater tolerance to fungal disease compared with alfalfa and clover. Although substantial amounts of soluble and insoluble substances were released by the seeds during the germination period, the plants were able to remove all the pollutants in wastewater and significant portions of those released substances. The total reductions in total solids, COD, NO3-N, NO2-N, phosphate and potassium ranged from 54.7% to 91.0%, 56.0% to 91.5%, 82.9% to 98.1%, 95.9% to 99.5%, 54.5% to 93.6% and 99.6% to 99.8%, respectively. Oat, barley and rye grow well in this type of hydroponic system and can be used as a fish feed after being supplemented with fat, Ca, Na, Mn and Fe. Oil seeds and the chlorides of these elements could be added to these plants when formulating the fish feed. For a continuous operation, a two-unit system could be configured to allow for one week germination and one week cleaning and startup in one unit while the other unit is in operation. PMID:15607774

  19. Seagrass feeding choices and digestive strategies of the herbivorous fish Sarpa salpa.

    PubMed

    Goldenberg, S U; Erzini, K

    2014-05-01

    This is the first study investigating the plant-herbivore interaction between Sarpa salpa, which has overgrazed seagrass transplants in Portugal, and the seagrasses Cymodocea nodosa, Zostera marina and Zostera noltii, which have been considered for restoration. When offered the choice between the three seagrasses in outdoor tanks, adult S. salpa clearly preferred Z. noltii. Testing the seagrasses separately, mean ± s.d. feeding rates ranged from 21 ± 11 g seagrass fresh mass kg⁻¹ fish mass day⁻¹ for Z. marina to 32 ± 9 g seagrass fresh mass kg⁻¹ fish mass day⁻¹ for C. nodosa and 40 ± 11 g seagrass fresh mass kg⁻¹ fish mass day⁻¹ for Z. noltii (temperature = 16° C). Food-processing rate in S. salpa did not differ between seagrasses, and there was no evidence of a regulation of processing rate according to food intake. Seagrasses differed substantially in nitrogen content and C:N, with C. nodosa containing the highest nitrogen content and lowest C:N (2·5 ± 0·1% and 14·0 ± 1·0), followed by Z. noltii (2·1 ± 0·1% and 17·0 ± 1·0) and Z. marina (1·4 ± 0·1% and 26·0 ± 2·0). Food-processing rate in S. salpa and the nutritional value of the seagrasses were not correlated with the observed feeding preference and rate. The study suggests that C. nodosa and Z. marina are less at risk of overgrazing by S. salpa and might thus be preferable to Z. noltii for seagrass restoration in areas with noticeable abundances of this fish. PMID:24684485

  20. Trophic characteristics of a mangrove fish community in Southwest Thailand: Important mangrove contribution and intraspecies feeding variability

    NASA Astrophysics Data System (ADS)

    Zagars, Matiss; Ikejima, Kou; Kasai, Akihide; Arai, Nobuaki; Tongnunui, Prasert

    2013-03-01

    Mangrove production has been found to make a major contribution to the nutrition of a fish community in the Sikao Creek mangrove estuary, Southwest Thailand. Gut content analysis and carbon and nitrogen stable isotope analysis were used to assess fish feeding behavior and trophic reliance on different primary producers (mangrove leaves, phytoplankton, microphytobenthos) focusing on 19 dominant fish species, and 4 potential fish food items. Cluster analysis identified 5 trophic groups and the IsoSource model indicated the importance of primary food sources in trophically supporting different fish species. Most analyzed fish species had carbon isotopic signatures that were more depleted than those reported in previous studies, and the IsoSource model indicated that mangrove leaves were an important primary food source. This may be a specific characteristic of our study site, which is not well connected to other productive coastal habitats that provide alternative primary food sources. Thus we suggest that food chains in trophically isolated mangrove estuaries of southwest Thailand are more dependent on mangrove tree production. We also assessed the relationship of individuality in fish feeding habits and variability of δ13C values and showed that several mangrove fish species have significant intraspecies variability in feeding habits, possibly due to high intraspecific competition.

  1. Waste feed from coastal fish farms: A trophic subsidy with compositional side-effects for wild gadoids

    NASA Astrophysics Data System (ADS)

    Fernandez-Jover, Damian; Martinez-Rubio, Laura; Sanchez-Jerez, Pablo; Bayle-Sempere, Just T.; Lopez Jimenez, Jose Angel; Martínez Lopez, Francisco Javier; Bjørn, Pål-Arne; Uglem, Ingebrigt; Dempster, Tim

    2011-03-01

    Aquaculture of carnivorous fish species in sea-cages typically uses artificial feeds, with a proportion of these feeds lost to the surrounding environment. This lost resource may provide a trophic subsidy to wild fish in the vicinity of fish farms, yet the physiological consequences of the consumption of waste feed by wild fish remain unclear. In two regions in Norway with intensive aquaculture, we tested whether wild saithe ( Pollachius virens) and Atlantic cod ( Gadus morhua) associated with fish farms (F assoc), where waste feed is readily available, had modified diets, condition and fatty acid (FA) compositions in their muscle and liver tissues compared to fish unassociated (UA) with farms. Stomach content analyses revealed that both cod and saithe consumed waste feed in the vicinity of farms (6-96% of their diet was composed of food pellets). This translated into elevated body and liver condition compared to fish caught distant from farms for cod at both locations and elevated body condition for saithe at one of the locations. As a consequence of a modified diet, we detected significantly increased concentrations of terrestrial-derived fatty acids (FAs) such as linoleic (18:2ω6) and oleic (18:1ω9) acids and decreased concentrations of DHA (22:6ω3) in the muscle and/or liver of F assoc cod and saithe when compared with UA fish. In addition, the ω3:ω6 ratio clearly differed between F assoc and UA fish. Linear discriminant analysis (LDA) correctly classified 97% of fish into F assoc or UA origin for both cod and saithe based on the FA composition of liver tissues, and 89% of cod and 86% of saithe into F assoc or UA origin based on the FA composition of muscle. Thus, LDA appears a useful tool for detecting the influence of fish farms on the FA composition of wild fish. Ready availability of waste feed with high protein and fat content provides a clear trophic subsidy to wild fish in coastal waters, yet whether the accompanying side-effect of altered fatty

  2. Feeding ecology of pelagic fish larvae and juveniles in slope waters of the Gulf of Mexico.

    PubMed

    Wells, R J D; Rooker, J R

    2009-11-01

    Stable isotope ratios of carbon (delta13C) and nitrogen (delta15N) were used to investigate feeding patterns of larval and early juvenile pelagic fishes in slope waters of the Gulf of Mexico. Contribution of organic matter supplied to fishes and trophic position within this pelagic food web was estimated in 2007 and 2008 by comparing dietary signatures of the two main producers in this ecosystem: phytoplankton [based on particulate organic matter (POM)] and Sargassum spp. Stable isotope ratios of POM and pelagic Sargassum spp. were significantly different from one another with delta13C values of POM depleted by 3-6 per thousand and delta15N values enriched by 2 relative to Sargassum spp. Stable isotope ratios were significantly different among the five pelagic fishes examined: blue marlin Makaira nigricans, dolphinfish Coryphaena hippurus, pompano dolphinfish Coryphaena equiselis, sailfish Istiophorus platypterus and swordfish Xiphias gladius. Mean delta13C values ranged almost 2 among fishes and were most depleted in I. platypterus. In addition, mean delta15N values ranged 4-5 with highest mean values found for both C. hippurus and C. equiselis and the lowest mean value for M. nigricans during both years. Increasing delta13C or delta15N with standard length suggested that shifts in trophic position and diet occurred during early life for several species examined. Results of a two-source mixing model suggest approximately an equal contribution of organic matter by both sources (POM=55%; pelagic Sargassum spp.=45%) to the early life stages of pelagic fishes examined. Contribution of organic matter, however, varied among species, and sensitivity analyses indicated that organic source estimates changed from 2 to 13% for a delta(13)C fractionation change of +/-0.25 per thousand or a delta15N fractionation change of +/-1.0 per thousand relative to original fractionation values. PMID:20738644

  3. Parallel evolutionary trajectories underlie the origin of giant suspension-feeding whales and bony fishes.

    PubMed

    Friedman, Matt

    2012-03-01

    Giant suspension feeders such as mysticete whales, basking and whale sharks, and the extinct (indicated by '†') †pachycormiform teleosts are conspicuous members of modern and fossil marine vertebrate faunas. Whether convergent anatomical features common to these clades arose along similar evolutionary pathways has remained unclear because of a lack of information surrounding the origins of all groups of large-bodied suspension feeders apart from baleen whales. New investigation reveals that the enigmatic ray-finned fish †Ohmdenia, from the Lower Jurassic (Toarcian, 183.0-175.6 Ma) Posidonia Shale Lagerstätte, represents the immediate sister group of edentulous †pachycormiforms, the longest lived radiation of large vertebrate suspension feeders. †Ohmdenia bisects the long morphological branch leading to suspension-feeding †pachycormiforms, providing information on the sequence of anatomical transformations preceding this major ecological shift that can be compared to changes associated with the origin of modern mysticetes. Similarities include initial modifications to jaw geometry associated with the reduction of dentition, followed by the loss of teeth. The evolution of largest body sizes within both radiations occurs only after the apparent onset of microphagy. Comparing the fit of contrasting evolutionary models to functionally relevant morphological measurements for whales and †pachycormiform fishes reveals strong support for a common adaptive peak shared by suspension-feeding members of both clades. PMID:21849314

  4. Mercury Exposure in Healthy Korean Weaning-Age Infants: Association with Growth, Feeding and Fish Intake

    PubMed Central

    Chang, Ju Young; Park, Jeong Su; Shin, Sue; Yang, Hye Ran; Moon, Jin Soo; Ko, Jae Sung

    2015-01-01

    Low-level mercury (Hg) exposure in infancy might be harmful to the physical growth as well as neurodevelopment of children. The aim of this study was to investigate postnatal Hg exposure and its relationship with anthropometry and dietary factors in late infancy. We recruited 252 healthy Korean infants between six and 24 months of age from an outpatient clinic during the 2009/2010 and 2013/2014 seasons. We measured the weight and height of the infants and collected dietary information using questionnaires. The Hg content of the hair and blood was assessed using inductively coupled plasma mass spectroscopy. The geometric mean Hg concentration in the hair and blood was 0.22 (95% confidence interval: 0.20–0.24) µg/g and 0.94 (n = 109, 95% confidence interval: 0.89–0.99) µg/L, respectively. The hair Hg concentration showed a good correlation with the blood Hg concentration (median hair-to-blood Hg ratio: 202.7, r = 0.462, p < 0.001) and was >1 µg/g in five infants. The hair Hg concentration showed significant correlations with weight gain after birth (Z-score of the weight for age—Z-score of the birthweight; r = −0.156, p = 0.015), the duration (months) of breastfeeding as the dominant method of feeding (r = 0.274, p < 0.001), and the duration of fish intake more than once per week (r = 0.138, p = 0.033). In an ordinal logistic regression analysis with categorical hair Hg content (quartiles), dietary factors, including breastfeeding as the dominant method of feeding in late infancy (cumulative odds ratio: 6.235, 95% confidence interval: 3.086–12.597, p < 0.001) and the monthly duration of fish intake more than once per week (cumulative odds ratio: 1.203, 95% confidence interval: 1.034–1.401; p = 0.017), were significantly associated with higher hair Hg content. Weight gain after birth was not, however, significantly associated with hair Hg content after adjustment for the duration of breastfeeding as the dominant method of feeding. Low-level Hg exposure

  5. Feeding biomechanics in Acanthostega and across the fish-tetrapod transition.

    PubMed

    Neenan, James M; Ruta, Marcello; Clack, Jennifer A; Rayfield, Emily J

    2014-04-22

    Acanthostega is one of the earliest and most primitive limbed vertebrates. Its numerous fish-like features indicate a primarily aquatic lifestyle, yet cranial suture morphology suggests that its skull is more similar to those of terrestrial taxa. Here, we apply geometric morphometrics and two-dimensional finite-element analysis to the lower jaws of Acanthostega and 22 other tetrapodomorph taxa in order to quantify morphological and functional changes across the fish-tetrapod transition. The jaw of Acanthostega is similar to that of certain tetrapodomorph fish and transitional Devonian taxa both morphologically (as indicated by its proximity to those taxa in morphospace) and functionally (as indicated by the distribution of stress values and relative magnitude of bite force). Our results suggest a slow tempo of morphological and biomechanical changes in the transition from Devonian tetrapod jaws to aquatic/semi-aquatic Carboniferous tetrapod jaws. We conclude that Acanthostega retained a primitively aquatic lifestyle and did not possess cranial adaptations for terrestrial feeding. PMID:24573844

  6. Investigation of the available technologies and their feasibility for the conversion of food waste into fish feed in Hong Kong.

    PubMed

    Cheng, Jack Y K; Lo, Irene M C

    2016-04-01

    Food waste is the largest constituent of municipal solid waste in Hong Kong, but food waste recycling is still in its infancy. With the imminent saturation of all landfill sites by 2020, multiple technologies are needed to boost up the food waste recycling rate in Hong Kong. Conversion of food waste into animal feeds is prevalent in Japan, South Korea, and Taiwan, treating over 40 % of their recycled food waste. This direction is worth exploring in Hong Kong once concerns over food safety are resolved. Fortunately, while feeding food waste to pigs and chickens poses threats to public health, feeding it to fish is considered low risk. In order to examine the feasibility of converting food waste into fish feed in Hong Kong, this paper investigates the market demand, technical viability, feed quality, regulatory hurdles, and potential contribution. The results show that a significant amount of food waste can be recycled by converting it into fish feed due to the enormous demand from feed factories in mainland China. Two conversion technologies, heat drying and black soldier fly bioconversion, are studied extensively. Black soldier fly bioconversion is preferable because the end-product, insect powder, is anticipated to gain import approval from mainland China. The authors suggest further research efforts to speed up its application for food waste recycling in urban cities. PMID:25982983

  7. Effects of feeding fermented fish on egg cholesterol content in hens.

    PubMed

    Loh, Teck-Chwen; Law, Fang-Ling; Goh, Yong-Meng; Foo, Hooi-Ling; Zulkifli, Idrus

    2009-02-01

    This study was conducted to investigate the effects of feeding fermented fish (FF) to layers on laying performance, and polyunsaturated fatty acid and cholesterol levels in eggs and plasma. A total of 96, 13-week-old Babcock B380 pullets were used in this study. They were randomly assigned to four numerically equal groups with eight replicates per treatment, three birds per replicate. All the birds were housed in individual cages. The dietary treatments were: Control diet, without FF; FF3 diet containing 3% (w/w) FF, FF6 diet containing 6% (w/w) FF and FF9 diet containing 9% (w/w) FF. The study was carried out for 16 weeks inclusive of two weeks of adjustment. Weekly feed intake and egg production were recorded. Blood plasma cholesterol and fatty acid profiles were assayed at the end of the experiment. FF did not enhance (P > 0.05) egg mass but (P < 0.05) decreased egg weight slightly. However, egg yolk cholesterol and plasma cholesterol concentrations were reduced (P < 0.05) by FF. The n-6:n-3 fatty acids ratio in the egg yolk (Control = 7.9, FF9 = 6.2) and plasma (Control = 10.6, FF9 = 6.2) were decreased by feeding FF. Moreover, FF was able to increase (P < 0.05) the docosahexaenoic acid (DHA) concentrations in egg yolk and plasma. In conclusion, this study demonstrated that FF increased DHA and reduced egg yolk cholesterol in poultry eggs. PMID:20163464

  8. Piscivorous fish exhibit temperature-influenced binge feeding during an annual prey pulse.

    PubMed

    Furey, Nathan B; Hinch, Scott G; Mesa, Matthew G; Beauchamp, David A

    2016-09-01

    Understanding the limits of consumption is important for determining trophic influences on ecosystems and predator adaptations to inconsistent prey availability. Fishes have been observed to consume beyond what is sustainable (i.e. digested on a daily basis), but this phenomenon of hyperphagia (or binge-feeding) is largely overlooked. We expect hyperphagia to be a short-term (1-day) event that is facilitated by gut volume providing capacity to store consumed food during periods of high prey availability to be later digested. We define how temperature, body size and food availability influence the degree of binge-feeding by comparing field observations with laboratory experiments of bull trout (Salvelinus confluentus), a large freshwater piscivore that experiences highly variable prey pulses. We also simulated bull trout consumption and growth during salmon smolt outmigrations under two scenarios: 1) daily consumption being dependent upon bioenergetically sustainable rates and 2) daily consumption being dependent upon available gut volume (i.e. consumption is equal to gut volume when empty and otherwise 'topping off' based on sustainable digestion rates). One-day consumption by laboratory-held bull trout during the first day of feeding experiments after fasting exceeded bioenergetically sustainable rates by 12- to 87-fold at low temperatures (3 °C) and by  ˜1·3-fold at 20 °C. The degree of binge-feeding by bull trout in the field was slightly reduced but largely in agreement with laboratory estimates, especially when prey availability was extremely high [during a sockeye salmon (Oncorhynchus nerka) smolt outmigration and at a counting fence where smolts are funnelled into high densities]. Consumption by bull trout at other settings were lower and more variable, but still regularly hyperphagic. Simulations demonstrated the ability to binge-feed increased cumulative consumption (16-32%) and cumulative growth (19-110%) relative to only feeding at

  9. Fluid dynamics of feeding behaviour in white-spotted bamboo sharks.

    PubMed

    Nauwelaerts, Sandra; Wilga, Cheryl D; Lauder, George V; Sanford, Christopher P

    2008-10-01

    Although the motor control of feeding is presumed to be generally conserved, some fishes are capable of modulating the feeding behaviour in response to prey type and or prey size. This led to the 'feeding modulation hypothesis', which states that rapid suction strikes are pre-programmed stereotyped events that proceed to completion once initiated regardless of sensory input. If this hypothesis holds true, successful strikes should be indistinguishable from unsuccessful strikes owing to a lack of feedback control in specialized suction feeding fishes. The hydrodynamics of suction feeding in white-spotted bamboo sharks (Chiloscyllium plagiosum) was studied in three behaviours: successful strikes, intraoral transports of prey and unsuccessful strikes. The area of the fluid velocity region around the head of feeding sharks was quantified using time-resolved digital particle image velocimetry (DPIV). The maximal size of the fluid velocity region is 56% larger in successful strikes than unsuccessful strikes (10.79 cm2 vs 6.90 cm2), but they do not differ in duration, indicating that strikes are modulated based on some aspect of the prey or simply as a result of decreased effort on the part of the predator. The hydrodynamic profiles of successful and unsuccessful strikes differ after 21 ms, a period probably too short to provide time to react through feedback control. The predator-to-prey distance is larger in missed strikes compared with successful strikes, indicating that insufficient suction is generated to compensate for the increased distance. An accuracy index distinguishes unsuccessful strikes (-0.26) from successful strikes (0.45 to 0.61). Successful strikes occur primarily between the horizontal axis of the mouth and the dorsal boundary of the ingested parcel of water, and missed prey are closer to the boundary or beyond. Suction transports are shorter in duration than suction strikes but have similar maximal fluid velocity areas to move the prey through the

  10. Potential changes in feeding behavior of Antarctic fish, Pseudotrematomus bernacchii (Boulenger, 1902) on the East Ongul Island, Antarctica

    NASA Astrophysics Data System (ADS)

    Chavanich, Suchana; Viyakarn, Voranop; Nomura, Daiki; Watanabe, Kentaro

    2015-12-01

    The feeding habits of the Antarctic fish Pseudotrematomus bernacchii (Previous name: Trematomus bernacchii) under the fast ice around Japanese Syowa Station were investigated in the summers of 2004/2005 and 2009/2010. The results showed that amphipods and krill were the major prey. However, there was a significant difference in the proportions of larger invertebrates such as squids, octopus and other crustaceans found in the fish stomachs between 2009/2010 and the previous years. Moreover, the percentage of amphipods and krill in fish stomachs declined over the 5-year period in all fish size classes. Several factors including sea ice melting, habitat and environmental changes might have influenced the pattern of feeding behavior.

  11. Biofilm forming abilities of Salmonella are correlated with persistence in fish meal- and feed factories

    PubMed Central

    Vestby, Lene K; Møretrø, Trond; Langsrud, Solveig; Heir, Even; Nesse, Live L

    2009-01-01

    Background Feed contaminated with Salmonella spp. constitutes a risk of Salmonella infections in animals, and subsequently in the consumers of animal products. Salmonella are occasionally isolated from the feed factory environment and some clones of Salmonella persist in the factory environment for several years. One hypothesis is that biofilm formation facilitates persistence by protecting bacteria against environmental stress, e.g. disinfection. The aim of this study was to investigate the biofilm forming potential of Salmonella strains from feed- and fishmeal factories. The study included 111 Salmonella strains isolated from Norwegian feed and fish meal factories in the period 1991–2006 of serovar Agona, serovar Montevideo, serovar Senftenberg and serovar Typhimurium. Results Significant differences were found between serovars regarding the abilities to form biofilm on polystyrene (microtiter plate assay) and in the air-liquid interface of nutrient broth (pellicle assay). Strains of serovar Agona and serovar Montevideo were good biofilm producers. In Norwegian factories, clones of these serovars have been observed to persist for several years. Most serovar Senftenberg clones appear to persist for a shorter period, and strains of this serovar were medium biofilm producers in our test systems. Strains of the serovar Typhimurium were relatively poor biofilm producers. Salmonella ser. Typhimurium clones have not been observed to persist even though this serovar is resident in Norwegian wild life. When classifying strains according to persistence or presumed non-persistence, persistent strains produced more biofilm than presumed non-persisting strains. Conclusion The results indicate a correlation between persistence and biofilm formation which suggests that biofilm forming ability may be an important factor for persistence of Salmonella in the factory environment. PMID:19473515

  12. Feeding ecology of indigenous and non-indigenous fish species within the family Sphyraenidae.

    PubMed

    Kalogirou, S; Mittermayer, F; Pihl, L; Wennhage, H

    2012-06-01

    The feeding ecology of two common indigenous (Sphyraena viridensis and Sphyraena sphyraena) and one abundant non-indigenous sphyraenid species, Sphyraena chrysotaenia, of Indo-Pacific Ocean origin, was investigated in an area of the eastern Mediterranean Sea. The stomach contents of 738 individuals of varying size, collected during the period December 2008 to August 2009, were examined. The dietary analyses revealed that all three species were specialized piscivores with a diet consisting of >90% fish, both by number and mass. Concurrent sampling of the fish assemblage made it possible to calculate selectivity as well as diet breadth and overlap of these strict piscivores. Even though several prey species were found in the stomachs of the three predators examined, selectivity towards Atherina boyeri was highly significant. For all species examined, >70% of the diet by mass was made up by three indigenous species of commercial value: Spicara smaris, Boops boops and A. boyeri. Diet breadth and size of prey increased with increasing body size for all predators. With increased body size, the diet overlap between indigenous and non-indigenous species decreased. This could be attributed to increased diet breadth and the specific life-history characteristics of indigenous species developing into larger individuals. During winter, the condition factor of the non-indigenous species was significantly lower than that of the indigenous, indicating that winter conditions in the Mediterranean Sea may limit its further expansion north and westward. With this study, the gap in knowledge of the feeding preferences of the most abundant piscivorous species found in coastal areas of the study region is filled. Additionally, the results indicate that non-indigenous species familial affiliation to indigenous ones does not facilitate invasion success. PMID:22650432

  13. Feeding habits of an endemic fish, Oxygymnocypris stewartii, in the Yarlung Zangbo River in Tibet, China

    USGS Publications Warehouse

    Huo, Bin; Xie, Cong Xin; Madenjian, Charles P.; Ma, Bao Shan; Yang, Xue Feng; Huang, Hai Ping

    2014-01-01

    Feeding habits of Oxygymnocypris stewartii were investigated based on monthly sampling in the Yarlung Zangbo River from August 2008 to August 2009. The gut contents of 194 individuals were analysed and quantified with numerical and gravimetric methods. This species can be considered a generalized and opportunistic predator feeding both on teleosts and aquatic insects. A multivariate analysis revealed noticeable variation in O. stewartii diet composition with fish size and season. The smaller specimens fed primarily on Cobitidae and Hydropsychidae. As they grew, Cyprinidae and Chironomidae larvae became important prey. The preferred food items were teleosts in summer and autumn. For winter and spring, the predominant prey switched to chironomidae larvae. Diet composition did not significantly vary between the sexes. Finally, a significant and positive correlation between predator and prey length was found. These findings provide the fundamental information better understanding the role of this important endemic species in the Yarlung Zangbo River food web.

  14. Diet and feeding of fish from Grande River, located below the Volta Grande Reservoir, MG-SP.

    PubMed

    Andrade, P M; Braga, F M S

    2005-08-01

    We compare the classic model of feeding of tropical fish by means of six bimonthly samplings using gillnets of varying mesh sizes that were inspected every twelve hours throughout a forty-eight hour period. The stomachs of the fish caught were classified in three categories according to quantity of food found. The amount of fat in the visceral cavity with respect to the energetic reserve deposition was also studied. The relative frequencies of the different categories of stomach repletion and fat deposition were examined for patterns of feeding seasonality. The stomachs considered full were examined to record diet composition. To assess the relative importance of the different food resources, we applied Feeding Importance Degree (FID), which is a useful index when difficulties exist in determining a common basis for volume, number, or weight of a given food item in different species, a common problem when dealing with fish species having different feeding habits. The fish species whose stomach contents were analyzed using the FID index were Serrasalmus spilopleura (Characidae), L. prolixa (Loricaridae), Schizodon nasutus (Anostomidae), and Pimelodus maculatus (Pimelodidae). Our findings indicate some contrasting elements, in dietary composition in relation to the classic model for tropical rivers. These factors include the importance of aquatic macrophytes, the lack of piscivorous species, and a lesser presence of allochthonous vegetation in the diet of the species studied. PMID:16341415

  15. Selective feeding by coral reef fishes on coral lesions associated with brown band and black band disease

    NASA Astrophysics Data System (ADS)

    Chong-Seng, K. M.; Cole, A. J.; Pratchett, M. S.; Willis, B. L.

    2011-06-01

    Recent studies have suggested that corallivorous fishes may be vectors for coral disease, but the extent to which fishes actually feed on and thereby potentially transmit coral pathogens is largely unknown. For this study, in situ video observations were used to assess the level to which fishes fed on diseased coral tissues at Lizard Island, northern Great Barrier Reef. Surveys conducted at multiple locations around Lizard Island revealed that coral disease prevalence, especially of brown band disease (BrB), was higher in lagoon and backreef locations than in exposed reef crests. Accordingly, video cameras were deployed in lagoon and backreef habitats to record feeding by fishes during 1-h periods on diseased sections of each of 44 different coral colonies. Twenty-five species from five fish families (Blennidae, Chaetodontidae, Gobiidae, Labridae and Pomacentridae) were observed to feed on infected coral tissues of staghorn species of Acropora that were naturally infected with black band disease (BBD) or brown band disease (BrB). Collectively, these fishes took an average of 18.6 (±5.6 SE) and 14.3 (±6.1 SE) bites per hour from BBD and BrB lesions, respectively. More than 40% (408/948 bites) and nearly 25% (314/1319 bites) of bites were observed on lesions associated with BBD and BrB, respectively, despite these bands each representing only about 1% of the substratum available. Moreover, many corallivorous fishes ( Labrichthys unilineatus, Chaetodon aureofasciatus, C. baronessa, C. lunulatus, C. trifascialis, Cheiloprion labiatus) selectively targeted disease lesions over adjacent healthy coral tissues. These findings highlight the important role that reef fishes may play in the dynamics of coral diseases, either as vectors for the spread of coral disease or in reducing coral disease progression through intensive and selective consumption of diseased coral tissues.

  16. Oryzias melastigma - an effective substitute for exotic larvicidal fishes: enhancement of its reproductive potential by supplementary feeding.

    PubMed

    Dutta, Abir Lal; Dey, Sajal Kumar; Chakraborty, Debargha; Manna, Asim Kumar; Manna, Pankaj Kumar

    2013-12-01

    A preliminary study was conducted on the efficacy of Oryzias melastigma in consuming mosquito larva so as to control mosquito and mosquito borne diseases, and enhancing its reproductive success using supplementary feed. Oryzias melastigma is a larvivore fish and widely distributed in the shallow water, wetlands of Gangetic plains and peninsular India. These studies indicate that O. melastigma is a prolific breeder and gregarious feeder of mosquito larvae. Increased reproduction by providing different supplementary feed, of which Ulothrix acted remarkably, may aid in wide spread use of this fish as a biological control measure against mosquitoes. One adult fish of any sex can consume 87.1% first instars mosquito larvae/day. So, early stages of mosquito larvae are effectively controlled, as compared to other successive stages. Ulothrix has considerable effect on egg production, successful hatching and regaining reproductive maturity of female in surprisingly quicker interval. PMID:23807913

  17. The biological role of pituitary adenylate cyclase-activating polypeptide (PACAP) in growth and feeding behavior in juvenile fish.

    PubMed

    Lugo, Juana Maria; Oliva, Aymé; Morales, Antonio; Reyes, Osvaldo; Garay, Hilda Elisa; Herrera, Fidel; Cabrales, Ania; Pérez, Ever; Estrada, Mario Pablo

    2010-11-01

    To date, many technologies have been developed to increase efficiency in aquaculture, but very few successful biotechnology molecules have arrived on the market. In this context, marine biotechnology has an opportunity to develop products to improve the output of fish in aquaculture. Published in vivo studies on the action of the pituitary adenylate cyclase-activating polypeptide (PACAP) in fish are scarce. Recently, our group, for the first time, demonstrated the biological role of this neuropeptide administrated by immersion baths in the growth and development of larval fish. In this work, we have evaluated the effects of recombinant Clarias gariepinus PACAP administration by intraperitoneal injection on growth performance and feeding behavior in juvenile fish. Our results showed the physiological role of this peptide for growth control in fish, including the juvenile stage, and confirm that its biological functions are well conserved in fish, since C. gariepinus PACAP stimulated growth in juvenile tilapia Oreochromis niloticus. In addition, we have observed that the growth-promoting effect of PACAP in juvenile tilapia was correlated with higher GH concentration in serum. With regard to the neuroendocrine regulation of growth control by PACAP, it was demonstrated that PACAP stimulates food intake in juvenile tilapia. In general, PACAP appears to act in the regulation of the growth control in juvenile fish. These findings propose that PACAP is a prominent target with the potential to stimulate fish growth in aquaculture. PMID:20853308

  18. Trace elements in farmed fish (Cyprinus carpio, Ctenopharyngodon idella and Oncorhynchus mykiss) from Beijing: implication from feed.

    PubMed

    Jiang, Haifeng; Qin, Dongli; Mou, Zhenbo; Zhao, Jiwei; Tang, Shizhan; Wu, Song; Gao, Lei

    2016-06-01

    Concentrations of 30 trace elements, Li, V, Cr, Mn, Fe, Ni, Cu, Mo, Zn, Se, Sr, Co, Al, Ti, As, Cs, Sc, Te, Ba, Ga, Pb, Sn, Cd, Sb, Ag, Tm, TI, Be, Hg and U in major cultured freshwater fish species (common carp-Cyprinus carpio, grass carp-Ctenopharyngodon idella and rainbow trout-Oncorhynchus mykiss) with the corresponding feed from 23 fish farms in Beijing, China, were investigated. The results revealed that Fe, Zn, Cu, Mn, Sr, Se were the major accumulated essential elements and Al, Ti were the major accumulated non-essential elements, while Mo, Co, Ga, Sn, Cd, Sb, Ag, Tm, U, TI, Be, Te, Pb and Hg were hardly detectable. Contents of investigated trace elements were close to or much lower than those in fish from other areas in China. Correlation analysis suggested that the elemental concentrations in those fish species were relatively constant and did not vary much with the fish feed. In comparison with the limits for aquafeeds and fish established by Chinese legislation, Cd in 37.5% of rainbow trout feeds and As in 20% of rainbow trout samples exceeded the maximum limit, assuming that inorganic As accounts for 10% of total As. Further health risk assessment showed that fish consumption would not pose risks to consumers as far as non-essential element contaminants are concerned. However, the carcinogenic risk of As in rainbow trout for the inhabitants in Beijing exceeded the acceptable level of 10(-)(4), to which more attention should be paid. PMID:26892032

  19. Replacing fish meal by food waste in feed pellets to culture lower trophic level fish containing acceptable levels of organochlorine pesticides: health risk assessments.

    PubMed

    Cheng, Zhang; Mo, Wing-Yin; Man, Yu-Bon; Nie, Xiang-Ping; Li, Kai-Bing; Wong, Ming-Hung

    2014-12-01

    The present study used food waste (collected from local hotels and restaurants) feed pellets in polyculture of low-trophic level fish [bighead (Aristichtys nobilis), grass carp (Ctenopharyngodon idellus), and mud carp (Cirrhina molitorella)] aiming at producing safe and quality products for local consumption. The results indicated that grass carp (hexachlorocyclohexanes (HCHs) <0.03; dichlorodiphenyltrichloroethanes (DDTs) 1.42-3.34 ng/g ww) and bighead carp (HCHs<0.03; DDTs 1.55-2.56 ng/g ww) fed with food waste feed pellets were relatively free of organochlorine pesticides (OCPs). The experimental ponds (water and sediment) were relatively free of OCPs, lowering the possibility of biomagnification of OCPs in the food chains within the ponds. The raw concentrations of OCPs extracted from the fish were not in the bioavailable form, which would ultimately reach bloodstream and exert adverse effects on human body. Health risk assessments based on digestible concentrations are commonly regarded as a more accurate method. The results of health risk assessments based on raw and digestible concentrations showed that the fish fed with food waste feed pellets were safe for consumption from the OCP perspective. PMID:25080070

  20. Stress, nutrition and parental care in a teleost fish: exploring mechanisms with supplemental feeding and cortisol manipulation.

    PubMed

    Zolderdo, A J; Algera, D A; Lawrence, M J; Gilmour, K M; Fast, M D; Thuswaldner, J; Willmore, W G; Cooke, S J

    2016-04-15

    Parental care is an essential life-history component of reproduction for many animal species, and it entails a suite of behavioural and physiological investments to enhance offspring survival. These investments can incur costs to the parent, reducing their energetic and physiological condition, future reproductive capabilities and survival. In fishes, relatively few studies have focused on how these physiological costs are mediated. Male smallmouth bass provide parental care for developing offspring until the brood reaches independence. During this energetically demanding life stage, males cease active foraging as they vigorously defend their offspring. Experimental manipulation of cortisol levels (via implantation) and food (via supplemental feeding) in parental males was used to investigate the fitness consequences of parental care. Improving the nutritional condition of nest-guarding males increased their reproductive success by reducing premature nest abandonment. However, supplemental feeding and cortisol treatment had no effect on parental care behaviours. Cortisol treatment reduced plasma lymphocyte numbers, but increased neutrophil and monocyte concentrations, indicating a shift in immune function. Supplemental feeding improved the physiological condition of parental fish by reducing the accumulation of oxidative injury. Specifically, supplemental feeding reduced the formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) on DNA nucleotides. Increasing the nutritional condition of parental fish can reduce the physiological cost associated with intensive parental activity and improve overall reproductive success, illustrating the importance of nutritional condition as a key modulator of parental fitness. PMID:26896551

  1. Assessing impacts of land-applied manure from concentrated animal feeding operations on fish populations and communities.

    PubMed

    Leet, Jessica K; Lee, Linda S; Gall, Heather E; Goforth, Reuben R; Sassman, Stephen; Gordon, Denise A; Lazorchak, James M; Smith, Mark E; Jafvert, Chad T; Javfert, Chad T; Sepúlveda, Maria S

    2012-12-18

    Concentrated animal feeding operation (CAFO) manure is a cost-effective fertilizer. In the Midwest, networks of subsurface tile-drains expedite transport of animal hormones and nutrients from land-applied CAFO manure to adjacent waterways. The objective of this study was to evaluate impacts of land-applied CAFO manure on fish populations and communities. Water chemistry including hormone, pesticide, and nutrient concentrations was characterized from study sites along with fish assemblage structure, growth, and endocrine disruption assessed in selected fish species. Although most CAFO water samples had hormone concentrations <1 ng/L, equivalent concentrations for 17β-E2 and 17α-TB peaked at >30 ng/L each during the period of spawning, hatching, and development for resident fishes. CAFO sites had lower fish species richness, and fishes exhibited faster somatic growth and lower reproductive condition compared to individuals from the reference site. Fathead minnows (Pimephales promelas) exposed to CAFO ditchwater during early developmental stages exhibited significantly skewed sex ratios toward males. Maximum observed hormone concentrations were well above the lowest observable effect concentrations for these hormones; however, complexities at the field scale make it difficult to directly relate hormone concentration and impacts on fish. Complicating factors include the consistent presence of pesticides and nutrients, and the difference in temperature and stream architecture of the CAFO-impacted ditches compared to the reference site (e.g., channelization, bottom substrate, shallow pools, and riparian cover). PMID:23171355

  2. Community structure and feeding ecology of mesopelagic fishes in the slope waters of King George Island (South Shetland Islands, Antarctica)

    NASA Astrophysics Data System (ADS)

    Pusch, C.; Hulley, P. A.; Kock, K.-H.

    2004-11-01

    The role of mesopelagic fishes in the Southern Ocean ecosystem and more particular their trophic effect on the standing stock of mesozooplankton is at present poorly understood. To get a deeper insight in the Antarctic mid-water ecosystem the mesopelagic fish community of the King George Island slope (South Shetland Islands) was sampled with a pelagic trawl in 1996. The community structure was analysed and the feeding ecology was studied of the five most abundant species. A total of 18 mesopelagic fish species in 10 families was identified. Of these, the Myctophidae was the most important family by species number (9 species), individual number (98.5% of all individuals) and fish wet weight (87.3% of the total weight). The assemblage was numerically dominated by four myctophids (Electrona antarctica, Gymnoscopelus braueri, Gymnoscopelus nicholsi, Protomyctophum bolini) and one gempilyd (Paradiplospinus gracilis). Multivariate statistical analysis of the mesopelagic fish data reveals two major groups of stations according to the sampled depth: a shallow group of stations (295-450 m depth) and a deeper group of stations (440-825 m depth). The change in relative abundance of mesopelagic fish species at 440-450 m coincides with the presence of warmer and denser Circumpolar Deep Water at and below these depths. Deeper stations were characterized by a higher density and increased diversity of mesopelagic fish species. The community patterns identified correlated well with the vertical depth distribution of the most abundant species. Dietary analysis reveals that myctophids are mostly zooplanktivorous, while the gempilyd P. gracilis is classified as a piscivorous predator. The small P. bolini feed mainly on copepods of the species Metridia gerlachei, while the most important prey item of the larger myctophids E. antarctica, G. braueri, and G. nicholsi were various species of euphausiids. Investigation of feeding chronology showed that G. nicholsi and P. bolini were feeding

  3. Sensing the strike of a predator fish depends on the specific gravity of a prey fish.

    PubMed

    Stewart, William J; McHenry, Matthew J

    2010-11-15

    The ability of a predator fish to capture a prey fish depends on the hydrodynamics of the prey and its behavioral response to the predator's strike. Despite the importance of this predator-prey interaction to the ecology and evolution of a diversity of fish, it is unclear what factors dictate a fish's ability to evade capture. The present study evaluated how the specific gravity of a prey fish's body affects the kinematics of prey capture and the signals detected by the lateral line system of the prey during the strike of a suction-feeding predator. The specific gravity of zebrafish (Danio rerio) larvae was measured with high precision from recordings of terminal velocity in solutions of varying density. This novel method found that specific gravity decreased by ∼5% (from 1.063, N=8, to 1.011, N=35) when the swim bladder inflates. To examine the functional consequences of this change, we developed a mathematical model of the hydrodynamics of prey in the flow field created by a suction-feeding predator. This model found that the observed decrease in specific gravity due to swim bladder inflation causes an 80% reduction of the flow velocity around the prey's body. Therefore, swim bladder inflation causes a substantial reduction in the flow signal that may be sensed by the lateral line system to evade capture. These findings demonstrate that the ability of a prey fish to sense a predator depends crucially on the specific gravity of the prey. PMID:21037055

  4. Non-indigenous species in Mediterranean fish assemblages: Contrasting feeding guilds of Posidonia oceanica meadows and sandy habitats

    NASA Astrophysics Data System (ADS)

    Kalogirou, S.; Wennhage, H.; Pihl, L.

    2012-01-01

    Quantitative sampling in combination with classification of fish species into six major feeding guilds revealed the position and contribution of non-indigenous species (NIS) in the food web of Posidonia oceanica and sandy habitats in an area of the eastern Mediterranean. In P. oceanica beds and on sandy bottoms 10 and five species, respectively, were non-indigenous fish of Indo-Pacific origin. The proportional contribution of NIS individuals on P. oceanica beds was lower than that of sandy bottoms (12.7 vs. 20.4%) a pattern that also followed for biomass (13.6 vs. 23.4%), indicating that low diverse systems may be more liable to introductions than species-rich communities. The two habitats had similar fish feeding guilds, but the biomass contribution from NIS varied within each guild, indicating different degrees of impact on the available resources. This study showed that only few non-indigenous fish species contributed to the differences in biomass between habitats. No support could be found in postulating that taxonomic affiliation could predict invasion success. Size was considered highly important due to habitat shift of species with increased size. Two of the aspects considered in this study, the chance of establishing vs. the chance of being very dominant will depend upon competitive abilities strongly coupled to size and grounds for habitat shift. However, success of establishment will also depend on appropriate food resources in the recipient community as well as competitive abilities and level of competition in the food web within habitats.

  5. Influence of substrate orientation on feeding kinematics and performance of algae-grazing Lake Malawi cichlid fishes.

    PubMed

    Rupp, Maxwell F; Hulsey, C Darrin

    2014-09-01

    Lake Malawi cichlids have been studied extensively in an effort to elucidate the mechanisms underlying their adaptive radiation. Both habitat partitioning and trophic specialization have been suggested to be critical ecological axes underlying the exceptional diversification of these fishes, but the mechanisms facilitating this divergence are often unclear. For instance, in the rock-dwelling mbuna of Lake Malawi, coexistence is likely tightly linked to how and where species feed on the algae coating all the surfaces of the rocky reefs they exclusively inhabit. Yet, although mbuna species often preferentially graze from particular substrate orientations, we understand very little about how substrate orientation influences feeding kinematics or feeding rates in any group of organisms. Therefore, for three species of mbuna, we quantified feeding kinematics and inferred the rates that algae could be ingested on substrates that mimicked the top, side and bottom of the algae-covered boulders these species utilize in Lake Malawi. A number of differences in feeding kinematics were found among species, and several of the kinematic variables were found to differ even within species when the fish grazed from different surface orientations. However, despite their preferences for particular microhabitats, we found no evidence for clear trade-offs in the rates that the three species were inferred to be able to obtain algae from different substrate orientations. Nevertheless, our results indicate microhabitat divergence linked to differences in feeding kinematics could have played a role in the origin and maintenance of the vast diversity of co-occurring Lake Malawi mbuna species. PMID:24948641

  6. Small estuarine fishes feed on large trematode cercariae: Lab and field investigations

    USGS Publications Warehouse

    Kaplan, A.T.; Rebhal, S.; Lafferty, K.D.; Kuris, A.M.

    2009-01-01

    In aquatic ecosystems, dense populations of snails can shed millions of digenean trematode cercariae every day. These short-lived, free-living larvae are rich in energy and present a potential resource for consumers. We investigated whether estuarine fishes eat cercariae shed by trematodes of the estuarine snail Cerithidea californica. In aquaria we presented cercariae from 10 native trematode species to 6 species of native estuarine fishes. Many of these fishes readily engorged on cercariae. To determine if fishes ate cercariae in the field, we collected the most common fish species, Fundulus parvipinnis (California killifish), from shallow water on rising tides when snails shed cercariae. Of 61 killifish, 3 had recognizable cercariae in their gut. Because cercariae are common in this estuary, they could be frequent sources of energy for small fishes. In turn, predation on cercariae by fishes (and other predators) could also reduce the transmission success of trematodes. ?? 2009 American Society of Parasitologists.

  7. A fish-feeding laboratory bioassay to assess the antipredatory activity of secondary metabolites from the tissues of marine organisms.

    PubMed

    Marty, Micah J; Pawlik, Joseph R

    2015-01-01

    Marine chemical ecology is a young discipline, having emerged from the collaboration of natural products chemists and marine ecologists in the 1980s with the goal of examining the ecological functions of secondary metabolites from the tissues of marine organisms. The result has been a progression of protocols that have increasingly refined the ecological relevance of the experimental approach. Here we present the most up-to-date version of a fish-feeding laboratory bioassay that enables investigators to assess the antipredatory activity of secondary metabolites from the tissues of marine organisms. Organic metabolites of all polarities are exhaustively extracted from the tissue of the target organism and reconstituted at natural concentrations in a nutritionally appropriate food matrix. Experimental food pellets are presented to a generalist predator in laboratory feeding assays to assess the antipredatory activity of the extract. The procedure described herein uses the bluehead, Thalassoma bifasciatum, to test the palatability of Caribbean marine invertebrates; however, the design may be readily adapted to other systems. Results obtained using this laboratory assay are an important prelude to field experiments that rely on the feeding responses of a full complement of potential predators. Additionally, this bioassay can be used to direct the isolation of feeding-deterrent metabolites through bioassay-guided fractionation. This feeding bioassay has advanced our understanding of the factors that control the distribution and abundance of marine invertebrates on Caribbean coral reefs and may inform investigations in diverse fields of inquiry, including pharmacology, biotechnology, and evolutionary ecology. PMID:25650625

  8. Molecular Dynamics Simulations of Water/Mucus Partition Coefficients for Feeding Stimulants in Fish and the Implications for Olfaction

    PubMed Central

    Rygg, Alex D.; van Duin, Adri C. T.; Craven, Brent A.

    2013-01-01

    The odorant partition coefficient is a physicochemical property that has been shown to dramatically influence odorant deposition patterns in the mammalian nose, leading to a chromatographic separation of odorants along the sensory epithelium. It is unknown whether a similar phenomenon occurs in fish. Here we utilize molecular dynamics simulations, based on a simplified molecular model of olfactory mucus, to calculate water/mucus partition coefficients for amino acid odorants (alanine, glycine, cysteine, and valine) that are known to elicit feeding behavior in fish. Both fresh water and salt water environments are considered. In fresh water, all four amino acids prefer the olfactory mucus phase to water, and the partition coefficient is shown to correlate with amino acid hydrophobicity. In salt water, a reversal in odorant partitioning is found, where each of the feeding stimulants (except glycine) prefer the water phase to olfactory mucus. This is due to the interactions between the salt ions and the odorant molecules (in the water phase), and between the salt and simplified mucin (in the olfactory mucus phase). Thus, slightly different odorant deposition patterns may occur in the fish olfactory organ in fresh and salt water environments. However, in both underwater environments we found that the variation of the water/mucus odorant partition coefficient is approximately one order of magnitude, in stark contrast to air/mucus odorant partition coefficients that can span up to six orders of magnitude. We therefore anticipate relatively similar deposition patterns for most amino acid odorants in the fish olfactory chamber. Thus, in contrast to terrestrial species, living in an underwater environment may preclude appreciable chromatographic odorant separation that may be used for spatial coding of odor identity across the olfactory epithelium. This is consistent with the reported lack of spatial organization of olfactory receptor neurons in the fish olfactory

  9. Daily rhythms of lipid metabolic gene expression in zebra fish liver: Response to light/dark and feeding cycles.

    PubMed

    Paredes, J F; López-Olmeda, J F; Martínez, F J; Sánchez-Vázquez, F J

    2015-01-01

    Despite numerous studies about fish nutrition and lipid metabolism, very little is known about the daily rhythm expression of lipogenesis and lipolysis genes. This research aimed to investigate the existence of daily rhythm expressions of the genes involved in lipid metabolism and their synchronization to different light/dark (LD) and feeding cycles in zebra fish liver. For this purpose, three groups of zebra fish were submitted to a 12:12 h LD cycle. A single daily meal was provided to each group at various times: in the middle of the light phase (ML); in the middle of the dark phase (MD); at random times. After 20 days of acclimation to these experimental conditions, liver samples were collected every 4 h in one 24-h cycle. The results revealed that most genes displayed a significant daily rhythm with an acrophase of expression in the dark phase. The acrophase of lipolytic genes (lipoprotein lipase - lpl, peroxisome proliferator-activated receptor - pparα and hydroxyacil CoA dehydrogenase - hadh) was displayed between ZT 02:17 h and ZT 18:31 h. That of lipogenic genes (leptin-a - lepa, peroxisome proliferator-activated receptor - pparγ, liver X receptor - lxr, insulin-like growth factor - igf1, sterol regulatory element-binding protein - srebp and fatty acid synthase - fas) was displayed between ZT 15:25 h and 20:06 h (dark phase). Feeding time barely influenced daily expression rhythms, except for lxr in the MD group, whose acrophase shifted by about 14 h compared with the ML group (ZT 04:31 h versus ZT 18:29 h, respectively). These results evidence a strong synchronization to the LD cycle, but not to feeding time, and most genes showed a nocturnal acrophase. These findings highlight the importance of considering light and feeding time to optimize lipid metabolism and feeding protocols in fish farming. PMID:26595085

  10. Suction muffler for refrigeration compressor

    DOEpatents

    Nelson, Richard T.; Middleton, Marc G.

    1983-01-01

    A hermetic refrigeration compressor includes a suction muffler formed from two pieces of plastic material mounted on the cylinder housing. One piece is cylindrical in shape with an end wall having an aperture for receiving a suction tube connected to the cylinder head. The other piece fits over and covers the other end of the cylindrical piece, and includes a flaring entrance horn which extends toward the return line on the sidewall of the compressor shell.

  11. Suction muffler for refrigeration compressor

    DOEpatents

    Nelson, R.T.; Middleton, M.G.

    1983-01-25

    A hermetic refrigeration compressor includes a suction muffler formed from two pieces of plastic material mounted on the cylinder housing. One piece is cylindrical in shape with an end wall having an aperture for receiving a suction tube connected to the cylinder head. The other piece fits over and covers the other end of the cylindrical piece, and includes a flaring entrance horn which extends toward the return line on the sidewall of the compressor shell. 5 figs.

  12. Application of mercury isotopes for tracing trophic transfer and internal distribution of mercury in marine fish feeding experiments.

    PubMed

    Kwon, Sae Yun; Blum, Joel D; Chirby, Michelle A; Chesney, Edward J

    2013-10-01

    Feeding experiments were performed to investigate mercury (Hg) isotope fractionation during trophic transfer and internal distribution of total Hg (THg) in marine fish on exposure to natural seafood. Young-of-the-year amberjack (Seriola dumerili) were fed with either blackfin tuna (Thunnus atlanticus; 2647 ng/g THg) or brown shrimp (Farfantepenaeus aztecus; 25.1 ng/g THg) for 80 d or 50 d, respectively, and dissected for muscle, liver, kidney, brain, and blood. After 30 d of tuna consumption, Hg isotopes (δ(202) Hg and Δ(199)Hg) of the amberjack organs shifted to the tuna value (δ(202)Hg = 0.55‰, Δ(199)Hg = 1.54‰,), demonstrating the absence of Hg isotope fractionation. When amberjack were fed a shrimp diet, there was an initial mixing of the amberjack organs toward the shrimp value (δ(202)Hg = -0.48‰, Δ(199)Hg = 0.32‰), followed by a cessation of further shifts in Δ(199)Hg and a small shift in δ(202)Hg. The failure of Δ(199)Hg to reach the shrimp value can be attributed to a reduction in Hg bioaccumulation from shrimp resulting from feeding inhibition and the δ(202)Hg shift can be attributed to a small internal fractionation during excretion. Given that the feeding rate and Hg concentration of the diet can influence internal Hg isotope distribution, these parameters must be considered in biosentinel fish studies. PMID:23787815

  13. Size-selective feeding on phytoplankton by two morpho-groups of the small freshwater fish Amblypharyngodon mola.

    PubMed

    Nandi, S; Saikia, S K

    2015-08-01

    Two morpho-groups (i.e., small, MGS and big, MGL) of the small freshwater fish Amblypharyngodon mola were studied for their feeding behaviour in the natural environment. Both the morpho-groups fed on a variety of phytoplankton including Cyanophyceae, Chlorophyceae, Bacillariophyceae and Euglenophyceae. The fish had more Chlorophyceae and Bacillariophyceae in their gut than other phytoplankton. Costello's selectivity plots revealed that the MGS fed on the smaller phytoplankters (2-6 µm in size), whereas the MGL fed on both the small and large (up to 12 µm in size) phytoplankters. The differences in mouth areas between the two morpho-groups were explained as a possible reason of size-selective feeding and contribute to overcome gape limitation in A. mola. This is further accompanied by the uniform pore size of the gills (2 µm) in all the morpho-groups. This study concluded that A. mola exhibits a size-dependent feeding strategy regulated by gape limitation at the ingestion level. With ontogenetic shifts, flexibility appears to overcome such a limitation in the MGL, having a wider mouth area supported by jaw opening ability. PMID:26084383

  14. Mexican blind cavefish use mouth suction to detect obstacles.

    PubMed

    Holzman, Roi; Perkol-Finkel, Shimrit; Zilman, Gregory

    2014-06-01

    Fish commonly use their lateral line system to detect moving bodies such as prey and predators. A remarkable case is the Mexican blind cavefish Astyanax fasciatus, which evolved the ability to detect non-moving obstacles. The swimming body of A. fasciatus generates fluid disturbances, the alteration of which by an obstacle can be sensed by the fish's lateral line system. It is generally accepted that these alterations can provide information on the distance to the obstacle. We observed that A. fasciatus swimming in an unfamiliar environment open and close their mouths at high frequency (0.7-4.5 Hz) in order to generate suction flows. We hypothesized that repeated mouth suction generates a hydrodynamic velocity field, which is altered by an obstacle, inducing pressure gradients in the neuromasts of the lateral line and corresponding strong lateral line stimuli. We observed that the frequency and rate of mouth-opening events varied with the fish's distance to obstacles, a hallmark of pulse-based navigation mechanisms such as echolocation. We formulated a mathematical model of this hitherto unrecognized mechanism of obstacle detection and parameterized it experimentally. This model suggests that suction flows induce lateral line stimuli that are weakly dependent on the fish's speed, and may be an order of magnitude stronger than the correspondent stimuli induced by the fish's gliding body. We illustrate that A. fasciatus can navigate non-visually using a combination of two deeply ancestral and highly conserved mechanisms of ray-finned fishes: the mechanism of sensing water motion by the lateral line system and the mechanism of generating water motion by mouth suction. PMID:24675558

  15. Environmental and water-quality operational studies. Prey selection and feeding patterns of fish in a Southern United States hydropower tailwater. Final report

    SciTech Connect

    Barwick, D.; Hudson, P.L.; Nestler, J.M.

    1985-10-01

    The downstream effects of peaking hydropower generation at Lake Hartwell Georgia-South Carolina, on the diel prey selection and feeding of four species of fish-silver redhorse (Moxostoma anisurum), redbreast sunfish (Lepomis auritus), green sunfish (L. cyanellus), and bluegill (L. macrochirus)--were determined. Aquatic insects (primarily dipterans, ephemeropterans, and trichopterans), crayfish, and terrestrial organisms (primarily insects) composed most of the food eaten. These fish fed primarily during daylight, before daily hydropower generation began, and little or no feeding occurred during generation. Consequently, few organisms entrained from the reservoir or displaced from the tailwater during hydropower generation were eaten by these fish.

  16. Development, validation and accreditation of a method for the determination of Pb, Cd, Cu and As in seafood and fish feed samples.

    PubMed

    Psoma, A K; Pasias, I N; Rousis, N I; Barkonikos, K A; Thomaidis, N S

    2014-05-15

    A rapid, sensitive, accurate and precise method for the determination of Pb, Cd, As and Cu in seafood and fish feed samples by Simultaneous Electrothermal Atomic Absorption Spectrometry was developed in regard to Council Directive 333/2007EC and ISO/IEC 17025 (2005). Different approaches were investigated in order to shorten the analysis time, always taking into account the sensitivity. For method validation, precision (repeatability and reproducibility) and accuracy by addition recovery tests have been assessed as performance criteria. The expanded uncertainties based on the Eurachem/Citac Guidelines were calculated. The method was accredited by the Hellenic Accreditation System and it was applied for an 8 years study in seafood (n=202) and fish feeds (n=275) from the Greek market. The annual and seasonal variation of the elemental content and correlation among the elemental content in fish feeds and the respective fish samples were also accomplished. PMID:24423504

  17. Evaluation of commercial marine fish feeds for production of juvenile cobia in recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of feeding three commercially available diets manufactured by three U.S. feed companies on production characteristics and body composition of juvenile cobia Rachycentron canadum reared in recirculating aquaculture systems (RAS) was evaluated in a 57 d growth trial. Juvenile cobia (26.7 +...

  18. Uptake and transmission of Toxoplasma gondii oocysts by migratory, filter-feeding fish.

    PubMed

    Massie, Gloeta N; Ware, Michael W; Villegas, Eric N; Black, Michael W

    2010-05-11

    From bottlenose dolphins, to walruses, to sea otters, the parasitic protozoan Toxoplasma gondii is infecting marine mammals around the world. Whereas the terrestrial transmission pathways of T. gondii are well-described, the transmission pathway by which marine mammals are being infected is unknown. We hypothesize that migratory filter feeders, specifically northern anchovies (Engraulis mordax) and Pacific sardines (Sardinops sagax), are serving as biotic vectors for T. gondii within the marine environment. By filtering oocysts from seawater, these fishes could be transporting the oocysts from nearshore to pelagic environments. In this study, we experimentally exposed northern anchovies and Pacific sardines to T. gondii oocysts under laboratory conditions. Following exposure, the fishes' alimentary canals were harvested and assayed for the presence of T. gondii by PCR. Fish exposed to as few as 1197 oocysts/L seawater tested positive for T. gondii by PCR. In total, the PCR assay detected T. gondii DNA in 66% (40/61) of the exposed fishes. Oocyst infectivity was confirmed by mouse bioassay: 30% (7/23) of mice developed toxoplasmosis when fed fish exposed to 100,000 oocysts/L. This study demonstrates that both northern anchovies and Pacific sardines can filter T. gondii oocysts out of seawater under experimental conditions. Our experiments with anchovies demonstrated that the oocysts persisted in the fish for at least 8h post-exposure and our experiments with sardines demonstrated that the oocysts remained infectious inside the fish's alimentary canals. PMID:20097009

  19. Feed Formulation and Manufacture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter provides information on feed formulation and manufacture. To formulate and manufacture high quality fish feeds, including tilapia feeds, one should have knowledge of nutrient requirements, nutrient composition, digestibility, and availability of feed ingredients; impacts of manufacturin...

  20. Protecting the hand that feeds us: seagrass (Zostera marina) serves as commercial juvenile fish habitat.

    PubMed

    Bertelli, Chiara M; Unsworth, Richard K F

    2014-06-30

    Although fisheries are of major economic and food security importance we still know little about specific juvenile habitats that support such production. This is a major issue given the degradation to and lack of protection afforded to potential juvenile habitats such as seagrass meadows. In the present study we investigate the role of seagrass in supporting juvenile fish of commercial value. By assessing seagrass relative to adjacent sand we determined the presence of abundant juvenile fish. Nine commercial species were recorded and the most abundant of these were Plaice, Pollock and Herring. We provide the first quantitative evidence of the presence of juvenile fish of commercial value in seagrass surrounding Great Britain. Although the species that we found in seagrass as juveniles are not obligate seagrass users the resources that seagrass meadows offer to these fish provide significant long-term fitness benefits, potentially enhancing the whole population. PMID:23998854

  1. Development of functional fish feed with natural ingredients to control heavy metals.

    PubMed

    Jia, Huijun; Ren, Huifeng; Maita, Masashi; Satoh, Shuichi; Endo, Hideaki; Hayashi, Tetsuhito

    2006-01-01

    The effects of two natural ingredients, Chinese parsley (CP) and chitosan (CT), on growth, accumulation, and excretion of cadmium in fish body and preservation of essential trace metals in the body were investigated by using rainbow trout that had been fed cadmium-added diet, low and high concentration, for 3 weeks. This pretest confirmed that cadmium was accumulated in the liver, kidney, and intestine of the test fish. The cadmium level of the fish, fed diet with CP or CT, was decreased by 18% and 24%, respectively, compared to that of the fish given the control diet. But CP and CT did not have an influence on normal growth of test fish and the levels of essential trace metals in the body. In addition, the level of cadmium was higher in liver than kidney in the high-cadmium dietary group, indicating the Cd level in kidney follows that of liver as kidney lies in the final stage of metabolism. The cadmium accumulation in the fish body was supposed to be reduced, by giving CP to increase the solubility of Cd to body fluid by conjugation into metallothioneins (MTs), while CT was supposed to be responsible for the physical adsorption of cadmium ions by glucosamine groups. PMID:20021015

  2. Polychlorinated Biphenyls (PCBs) in Predator and Bottom-Feeding Fish from Abiquiu and Cochiti Reservoirs in North-Central New Mexico

    SciTech Connect

    G.J. Gonzales, P.R. Fresquez

    2006-03-01

    Concern has existed for years that the Los Alamos National Laboratory (LANL), a complex of nuclear weapons research and support facilities, has released polychlorinated biphenyls (PCBs) to the environment that may have reached adjacent bodies of water through canyons that connect them. In 1997, we began measuring PCBs in fish in the Rio Grande upstream and downstream of ephemeral streams that cross LANL and later began sampling fish in Abiquiu and Cochiti reservoirs, which are situated on the Rio Chama and Rio Grande upstream and downstream of LANL, respectively. In 2005, six species of fish from Abiquiu and Cochiti reservoirs were collected and the edible portion (fillets) was analyzed for 209 possible PCB congeners. Fish from the reservoirs were last sampled in 2001. Mean total PCB concentrations in fish from Abiquiu Reservoir ({mu} = 2.4 ng/g) were statistically similar ({alpha} = 0.01; P (T{le}t) [range = 0.23-0.71]) to mean total PCB concentrations in fish from Cochiti Reservoir ({mu} = 2.7 ng/g), implying that LANL is not the source of PCBs in fish in Cochiti Reservoir. The levels of PCBs in fish from Cochiti Reservoir generally appear to be declining, at least since 2001, which is when PCB levels might have peaked resulting from storm water runoff after the Cerro Grande Fire. Although a PCB ''fingerprinting'' method can be used to relate PCB ''signatures'' in one area to signatures in another area, this method of implicating the source of PCBs cannot be effectively used for biota because they alter the PCB signature through metabolic processes. Regardless of the source of the PCBs, certain species of fish (catfish and carpsuckers) at both Abiquiu and Cochiti reservoirs continue to harbor levels of PCBs that could be harmful to human health if they are consistently eaten over a long period of time. Bottom-feeding fish (carpsucker and catfish) from Cochiti Reservoir contained statistically higher levels of total PCBs ({mu} = 4.25 ng/g-fillet-wet) than predator

  3. Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus).

    PubMed

    Besson, M; Komen, H; Aubin, J; de Boer, I J M; Poelman, M; Quillet, E; Vancoillie, C; Vandeputte, M; van Arendonk, J A M

    2014-12-01

    In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal growth coefficient (TGC) and the feed conversion ratio (FCR). This approach was applied to a farm producing African catfish (Clarias gariepinus) in a recirculating aquaculture system (RAS). In the RAS, 2 factors could limit production level: the nitrogen treatment capacity of the biofilter or the fish density in rearing tanks at harvest. Profit calculation includes revenue from fish sales, cost of juveniles, cost of feed, cost of waste water treatment, and fixed costs. In the reference scenario, profit was modeled to zero. EV were calculated as the difference in profit per kilogram of fish between the current population mean for both traits (µt) and the next generation of selective breeding (µt+Δt) for either TGC or FCR. EV of TGC and FCR were calculated for three generations of hypothetical selection on either TGC or FCR (respectively 6.8% and 7.6% improvement per generation). The results show that changes in TGC and FCR can affect both the number of fish that can be stocked (number of batches per year and number of fish per batch) and the factor limiting production. The EV of TGC and FCR vary and depend on the limiting factors. When dissolved NH3-N is the limiting factor for both µt and µt+Δt, increasing TGC decreases the number of fish that can be stocked but increases the number of batches that can be grown. As a result, profit remains constant and EVTGC is zero. Increasing FCR, however, increases the number of fish stocked and the ratio of fish produced per kilogram of feed consumed ("economic efficiency"). The EVFCR is 0.14 €/kg of fish, and profit per kilogram of fish increases by about 10%. When density is the limiting factor for both µt and µt+Δt, the

  4. Effect of substituting live feed with formulated feed on the reproductive performance and fry survival of Siamese fighting fish, Betta splendens (Regan, 1910).

    PubMed

    Mandal, Sagar C; Kohli, Mahinder P S; Das, Pronob; Singh, Soibam K; Munilkumar, Sukham; Sarma, Kamal; Baruah, Kartik

    2012-04-01

    This study aimed to elucidate the effect of partial or complete replacement of live feed (LF) (Tubifex) with formulated feed (FF) on the reproductive performance of Betta splendens. Three hundred B. splendens fry (average weight 0.19 ± 0.01 g) were equally distributed into five different groups, each with three replicates. They were fed for 105 days with following different diets: control (C)-100% LF; T1-75% LF, 25% FF; T2-50% LF, 50% FF; T3-25% LF, 75% FF, and T4-100% FF. Results showed that the average number of hatched larvae (654 ± 101) and fry survival after 2 weeks of rearing (428 ± 70), after completion of three spawning, were recorded highest in the control group, which was, however, not significantly different from the T1, T2, and T3 groups. At the end of the feeding trial, the highest hatching percentage (90.3%) was registered in the T2 group, which was not significantly different from the control and T1 groups. The T2 group also recorded highest fry survival (65.54%) after completion of three spawning, which was not significantly (P < 0.05) different from the T1 and T3 groups. Control diet contained higher saturated fatty acid (63.23%) than formulated diet (29.80%). In the whole-body tissue, highest level of EPA (0.42%) and DHA (3.13%) were found in the T4 group followed by T3 group. The DHA/EPA ration was recorded highest in the T2 group (10.96%), which did not differ significantly from the T1 and T3 groups. Significant positive correlation was observed between saturated fatty acid levels in fish whole-body tissue and number of hatched larvae (Y = 30.81 × -825.3, R(2) = 0.968) and fry survival after 2 weeks of rearing (Y = 21.38 × -580.9, R(2) = 0.967). Considering all these factors, it can be concluded that the live feed Tubifex can be replaced up to 50% without any adverse effect on the reproductive performance and fry survival of B. splendens. PMID:21710171

  5. Stuck suction catheter in endotracheal tube.

    PubMed

    Raut, Monish S; Joshi, Sandeep; Maheshwari, Arun

    2015-02-01

    Endotracheal tube (ETT) suction is essential to clear secretions so that airway patency can be maintained. Stuck suction catheter in ETT is an uncommon event, and it can be dangerous in patients with difficult airway cases. PMID:25722554

  6. Stuck suction catheter in endotracheal tube

    PubMed Central

    Raut, Monish S.; Joshi, Sandeep; Maheshwari, Arun

    2015-01-01

    Endotracheal tube (ETT) suction is essential to clear secretions so that airway patency can be maintained. Stuck suction catheter in ETT is an uncommon event, and it can be dangerous in patients with difficult airway cases. PMID:25722554

  7. Functional Feed Assessment on Litopenaeus vannamei Using 100% Fish Meal Replacement by Soybean Meal, High Levels of Complex Carbohydrates and Bacillus Probiotic Strains

    PubMed Central

    Olmos, Jorge; Ochoa, Leonel; Paniagua-Michel, Jesus; Contreras, Rosalia

    2011-01-01

    Functional feed supplemented with alternative-economic nutrient sources (protein, carbohydrates, lipids) and probiotics are being considered in shrimp/fish aquaculture production systems as an option to increase yield and profits and to reduce water pollution. In this study the probiotic potential to formulate functional feeds have been evaluated using four dietary treatments: Treatment 1 (B + Bs); Bacillus subtilis potential probiotic strain was supplemented to a soybeanmeal (SBM)—carbohydrates (CHO) basal feed. Treatment 2 (B + Bm); Bacillus megaterium potential probiotic strain was supplemented to the same SBM-CHO basal feed. In Treatment 3 (B); SBM-CHO basal feed was not supplemented with probiotic strains. Treatment 4 (C); fishmeal commercial feed (FM) was utilized as positive control. Feeding trials evaluated the survival, growth, and food conversion ratio and stress tolerance of juvenile Litopenaeus vannamei (Boone) Pacific white shrimp. Best overall shrimp performance was observed for animals fed with Treatment 1 (B+Bs); additionally, stress tolerance and hemolymph metabolites also showed the best performance in this treatment. SBM-CHO basal feed not supplemented with probiotic strains (B) presented smaller growth and lower feed conversion ratio (FCR). Shrimps fed with the fishmeal commercial feed (C) presented the lowest stress tolerance to high ammonia and low oxygen levels. Specifically selected B. subtilis strains are recommended to formulate functional and economical feeds containing high levels of vegetable; protein and carbohydrates as main dietary sources in L. vannamei cultures. PMID:21747750

  8. Functional feed assessment on Litopenaeus vannamei using 100% fish meal replacement by soybean meal, high levels of complex carbohydrates and Bacillus probiotic strains.

    PubMed

    Olmos, Jorge; Ochoa, Leonel; Paniagua-Michel, Jesus; Contreras, Rosalia

    2011-01-01

    Functional feed supplemented with alternative-economic nutrient sources (protein, carbohydrates, lipids) and probiotics are being considered in shrimp/fish aquaculture production systems as an option to increase yield and profits and to reduce water pollution. In this study the probiotic potential to formulate functional feeds have been evaluated using four dietary treatments: Treatment 1 (B + Bs); Bacillus subtilis potential probiotic strain was supplemented to a soybeanmeal (SBM)-carbohydrates (CHO) basal feed. Treatment 2 (B + Bm); Bacillus megaterium potential probiotic strain was supplemented to the same SBM-CHO basal feed. In Treatment 3 (B); SBM-CHO basal feed was not supplemented with probiotic strains. Treatment 4 (C); fishmeal commercial feed (FM) was utilized as positive control. Feeding trials evaluated the survival, growth, and food conversion ratio and stress tolerance of juvenile Litopenaeus vannamei (Boone) Pacific white shrimp. Best overall shrimp performance was observed for animals fed with Treatment 1 (B+Bs); additionally, stress tolerance and hemolymph metabolites also showed the best performance in this treatment. SBM-CHO basal feed not supplemented with probiotic strains (B) presented smaller growth and lower feed conversion ratio (FCR). Shrimps fed with the fishmeal commercial feed (C) presented the lowest stress tolerance to high ammonia and low oxygen levels. Specifically selected B. subtilis strains are recommended to formulate functional and economical feeds containing high levels of vegetable; protein and carbohydrates as main dietary sources in L. vannamei cultures. PMID:21747750

  9. Determination of selenium by GFAAS in slurries of fish feces to estimate the bioavailability of this micronutrient in feed used in pisciculture.

    PubMed

    Silva, Fábio A; Neves, Renato C F; Quintero-Pinto, Luis G; Padilha, Cilene C F; Jorge, Sônia M A; Barros, Margarida M; Pezzato, Luiz E; Padilha, Pedro M

    2007-07-01

    This paper presents a simple, fast and sensitive method to determine selenium in samples of feces and of fish feed by graphite furnace atomic absorption spectrometry (GFAAS) through the direct introduction of slurries of the samples into the spectrometer's graphite tube. The limits of detection (LOD) and quantification (LOQ) calculated for 20 readings of the blank of the standard slurries (0.50% m/v of feces or feed devoid of selenium) were 0.31 microg l(-1) and 1.03 microg l(-1), respectively, for the standard feces slurries and 0.35 microg l(-1) and 1.16 microg l(-1), respectively, for the standard feed slurries. The proposed method was applied in studies of bioavailability of selenium in different fish feeds and the results proved consistent with that obtained from samples mineralized by acid digestion using the microwave oven. PMID:17448523

  10. A game of keep-away: feeding the fish and not the pond

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytic acid is a storage form of phosphorus in many plants. Its levels rise in the diet along with the inclusion rate of plant-based materials. Our measurements have found that phytic acid levels can be as high as 2% of catfish diets (40 lbs/ton of feed). However, phytic acid is largely indigestib...

  11. Evidence of a specialized feeding niche in a Late Triassic ray-finned fish: evolution of multidenticulate teeth and benthic scraping in †Hemicalypterus.

    PubMed

    Gibson, Sarah Z

    2015-04-01

    Fishes have evolved to exploit multiple ecological niches. Extant fishes in both marine (e.g., rabbitfishes, surgeonfishes) and freshwater systems (e.g., haplochromine cichlids, characiforms) have evolved specialized, scoop-like, multidenticulate teeth for benthic scraping, feeding primarily on algae. Here, I report evidence of the oldest example of specialized multidenticulate dentition in a ray-finned fish, †Hemicalypterus weiri, from the Upper Triassic Chinle Formation of southeastern Utah (∼210-205 Ma), USA. †H. weiri is a lower actinopterygian species that is phylogenetically remote from modern fishes, and has evolved specialized teeth that converge with those of several living teleost fishes (e.g., characiforms, cichlids, acanthurids, siganids), with a likely function of these teeth being to scrape algae off a rock substrate. This finding contradicts previously held notions that fishes with multicuspid, scoop-like dentition were restricted to teleosts, and indicates that ray-finned fishes were diversifying into different trophic niches and exploring different modes of feeding earlier in their history than previously thought, fundamentally altering our perceptions of the ecological roles of fishes during the Mesozoic. PMID:25686871

  12. Evidence of a specialized feeding niche in a Late Triassic ray-finned fish: evolution of multidenticulate teeth and benthic scraping in † Hemicalypterus

    NASA Astrophysics Data System (ADS)

    Gibson, Sarah Z.

    2015-04-01

    Fishes have evolved to exploit multiple ecological niches. Extant fishes in both marine (e.g., rabbitfishes, surgeonfishes) and freshwater systems (e.g., haplochromine cichlids, characiforms) have evolved specialized, scoop-like, multidenticulate teeth for benthic scraping, feeding primarily on algae. Here, I report evidence of the oldest example of specialized multidenticulate dentition in a ray-finned fish, † Hemicalypterus weiri, from the Upper Triassic Chinle Formation of southeastern Utah (˜210-205 Ma), USA. † H. weiri is a lower actinopterygian species that is phylogenetically remote from modern fishes, and has evolved specialized teeth that converge with those of several living teleost fishes (e.g., characiforms, cichlids, acanthurids, siganids), with a likely function of these teeth being to scrape algae off a rock substrate. This finding contradicts previously held notions that fishes with multicuspid, scoop-like dentition were restricted to teleosts, and indicates that ray-finned fishes were diversifying into different trophic niches and exploring different modes of feeding earlier in their history than previously thought, fundamentally altering our perceptions of the ecological roles of fishes during the Mesozoic.

  13. Amending reduced fish-meal feeds with marine lecithin, but not soy lecithin, improves the growth of juvenile cobia and may attenuate heightened responses to stress challenge.

    PubMed

    Trushenski, J; Schwarz, M; Pessoa, W V N; Mulligan, B; Crouse, C; Gause, B; Yamamoto, F; Delbos, B

    2013-02-01

    Sparing of marine resources in aquafeeds can be environmentally and economically advantageous; however, fish meal (FM) replacement can affect the production performance and physiological competence. Phospholipids are increasingly understood to be involved in maintaining growth and vigour in fish and may be deficient in reduced FM formulations. Accordingly, we evaluated the growth and stress tolerance of juvenile cobia fed typical (50% FM) or reduced FM feeds (12% FM) with or without phospholipid amendment [1% marine lecithin (12% FM + Marine PL) or soy lecithin (12% FM + Soy PL)] for 6 weeks in triplicate tanks (N = 3) in a recirculation aquaculture system. The 50% FM feed yielded significantly superior growth and growth efficiency in comparison with the 12% FM and 12% FM+ Soy PL feeds, but the 12% FM+ Marine PL feed yielded comparable results to 50% FM feed. A low-water stress challenge induced elevated plasma glucose, cortisol and lactate levels in all treatments. However, a significant interaction (diet × stress) effect suggested a lesser cortisol response among fish fed the 12% FM+ Marine PL and 50% FM diets. These findings demonstrate that growth performance and, perhaps, resilience of cobia raised on reduced FM feeds may be improved by the addition of marine-origin phospholipid to the diet. PMID:22106957

  14. Persistent organic pollutants (POPs) in fish with different feeding habits inhabiting a shallow lake ecosystem.

    PubMed

    Barni, María F Silva; Ondarza, Paola M; Gonzalez, Mariana; Da Cuña, Rodrigo; Meijide, Fernando; Grosman, Fabián; Sanzano, Pablo; Lo Nostro, Fabiana L; Miglioranza, Karina S B

    2016-04-15

    The occurrence of persistent organic pollutants (POPs) in the environment can affect organisms inhabiting aquatic systems, in particular shallow lakes that are vulnerable to environmental stressors. This study aimed to assess POPs accumulation and changes at histological and physiological levels in tissues of three fish species with different trophic habits. Gills, brain, muscle, liver and gonads of Odontesthes bonariensis, Oligosarcus jenynsii and Cyphocharax voga were collected from the shallow lake La Peregrina, located in an agricultural area from Argentina. In addition, contaminant levels in surface water (SW), suspended particulate matter (SPM) and bottom sediments (BS) were assessed. Histological lesions were evaluated in fish tissues and levels of vitellogenin (VTG) were assessed in plasma of male fish in order to correlate these alterations with the presence of POPs in the environment. Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were determined by GC-ECD. Biotic and abiotic samples showed the same POPs distribution pattern: OCPs>PCBs>PBDEs. Although tissue distribution of OCPs was species-specific, muscle showed the lowest levels in all species. The most abundant contaminants were endosulfans, suggesting their widespread use in the area. O. bonariensis showed the highest endosulfans levels in liver (184.2-219ngg(-1)wet w), which was associated with the high SPM levels considering this species is a filter feeder. The occurrence of PCBs and PBDEs shows the ubiquity of these pollutants in the area. Histological lesions in gills and liver of O. bonariensis and O. jenynsii, might be related with the high levels of endosulfans in these organs. The detection of VTG in males warns about a possible exposure to estrogenic compounds in the environment. In conclusion, the simultaneous exposure of fish to multiple environmental pollutants leads to different alterations, so measures should be taken in

  15. Hybrid striped bass feeds based on fish oil, beef tallow, and eicosapentaenoic acid/docosahexaenoic acid supplements: Insight regarding fish oil sparing and demand for -3 long-chain polyunsaturated fatty acids.

    PubMed

    Bowzer, J; Jackson, C; Trushenski, J

    2016-03-01

    Previous research suggests that saturated (SFA) and monounsaturated fatty acid (MUFA) rich lipids, including beef tallow, can make utilization or diet-to-tissue transfer of long-chain polyunsaturated fatty acids (LC-PUFA) more efficient. We hypothesized that using beef tallow as an alternative to fish oil may effectively reduce the LC-PUFA demand of hybrid striped bass × and allow for greater fish oil sparing. Accordingly, we evaluated growth performance and tissue fatty acid profiles of juvenile fish (23.7 ± 0.3 g) fed diets containing menhaden fish oil (considered an ideal source of LC-PUFA for this taxon), beef tallow (BEEF ONLY), or beef tallow amended with purified sources of eicosapentaenoic acid (EPA) and/or docosahexaenoic acid (DHA) to achieve levels corresponding to 50 or 100% of those observed in the FISH ONLY feed. Diets were randomly assigned to quadruplicate tanks of fish ( = 4; 10 fish/tank), and fish were fed assigned diets to apparent satiation once daily for 10 wk. Survival (98-100%) was equivalent among treatments, but weight gain (117-180%), specific growth rate (1.1-1.5% BW/d), feed intake (1.4-1.8% BW/d), thermal growth coefficient (0.50-0.70), and feed conversion ratio (FCR; 1.1-1.4, DM basis) varied. Except for FCR, no differences were observed between the FISH ONLY and BEEF ONLY treatments, but performance was generally numerically superior among fish fed the diets containing beef tallow supplemented with DHA at the 100% or both EPA and DHA at the 50% or 100% level. Tissue fatty acid composition was significantly distorted in favor among fish fed the beef tallow-based feeds; however, profile distortion was most overt in peripheral tissues. Results suggest that beef tallow may be used as a primary lipid source in practical diets for hybrid striped bass, but performance may be improved by supplementation with LC-PUFA, particularly DHA. Furthermore, our results suggest that -3 LC-PUFA requirements reported for hybrid striped bass may not be

  16. Stochastic feeding of fish larvae and their metabolic handling of starvation

    NASA Astrophysics Data System (ADS)

    Augustine, S.; Litvak, M. K.; Kooijman, S. A. L. M.

    2011-11-01

    Developmental patterns of yolk-sac larvae are well captured by the standard DEB model: (i) when feeding is delayed post birth the size at which post-feeding growth begins is reduced but the rate of growth post-feeding is unaffected and (ii) maternal effects (initial energy in egg) show up as differences in condition at birth and maximum length of non fed individuals. We extended the standard DEB model in two ways to account for starvation. (I): if somatic maintenance can no longer be paid structure is also mobilized to cover the costs, but at an extra cost-conversion efficiency of structure to energy. Death occurs if structure reaches a fraction of the maximum at the onset of shrinking. (II): if maturity maintenance can no longer be paid then maturity level decays exponentially (rejuvenation). Hazard due to rejuvenation is proportional to the difference between maturity and the maximum maturity at the onset of rejuvenation. We performed Monte Carlo simulation studies which treat feeding as a random process to evaluate the contribution of the metabolic handling of starvation to early teleost life history. The simulations suggest that food density strongly impacts growth, energy reserves, mineral fluxes, hazard and mortality from shrinking. Environmental factors can soon override maternal induced differences between individuals. Moreover in the low food density, simulated individuals from eggs of lower caloric content experience mortality from shrinking earlier than their counterparts issued from higher energy eggs. Empirically observed patterns of real data, i.e. high scatter in respiration in combination with low scatter in lengths, can be expected when the metabolism is treated as a deterministic system while behaviourally controlled input is stochastic. At low food densities where mortality from shrinking reaches 10% almost all individuals experience hazard due to rejuvenation. This hazard is difficult to access experimentally but represents moments of heightened

  17. Determination of chromium by GFAAS in slurries of fish feces to estimate the apparent digestibility of nutrients in feed used in pisciculture.

    PubMed

    Silva, Fabio Arlindo; Padilha, Cilene C Federici; Pezzato, Luis Edvaldo; Barros, Margarida Maria; Padilha, Pedro M

    2006-06-15

    This paper presents a simple, fast and sensitive method to determine chromic oxide (used as a biological marker of fish feed) in samples of fish feces by GFAAS through the direct introduction of slurries of the samples into the spectrometer's graphite tube. The standard samples of feces and of fish feed containing 0.10-1.00mgkg(-1) of Cr(2)O(3) were pre-frozen for 1min in liquid nitrogen and then ground a cryogenic mill for 2min, which reduced the samples' grain size to less than 60mum. The standard slurries were prepared by mixing 20mg of standard samples of fish feed or feces with 1mL of a solution containing 0.05% (v/v) of Triton X-100 and 0.50% (v/v) of suprapure HNO(3) directly in the spectrometer's automatic sampling glass. The final concentrations of Cr(2)O(3) present in the standard slurries were 2, 4, 8, 16 and 20mugL(-1). After sonicating the mixture for 20s, 10muL of standard slurries were injected into the graphite tube, whose internal wall was lined with a metallic palladium film that acted as a permanent chemical modifier. The limits of detection (LOD) and quantification (LOQ) calculated for 20 readings of the blank of the standard slurries (2%, m/v of feces or feed devoid of minerals) were 0.81 and 2.70mugL(-1) of Cr(2)O(3) for the standard feces slurries, 0.84 and 2.83mugL(-1) of Cr(2)O(3) for the standard feed slurries. The proposed method was applied in studies of nutrient digestibility of different fish feeds and its results proved compatible with the results obtained from samples pre-mineralized by acid digestion. PMID:18970675

  18. Analysis of Tank 38H (HTF-38-15-119, 127) Surface, Subsurface and Tank 43H (HTF-43-15-116, 117 and 118) Surface, Feed Pump Suction and Jet Suction Subsurface Supernatant Samples in Support of Enrichment, Corrosion Control and Salt Batch Planning Programs

    SciTech Connect

    Oji, L.

    2015-12-17

    Compositional feed limits have been established to ensure that a nuclear criticality event for the 2H and 3H Evaporators is not possible. The Enrichment Control Program (ECP) requires feed sampling to determine the equivalent enriched uranium content prior to transfer of waste other than recycle transfers (requires sampling to determine the equivalent enriched uranium at two locations in Tanks 38H and 43H every 26 weeks) The Corrosion Control Program (CCP) establishes concentration and temperature limits for key constituents and periodic sampling and analysis to confirm that waste supernate is within these limits. This report provides the results of analyses on Tanks 38H and 43H surface and subsurface supernatant liquid samples in support of the ECP, the CCP, and the Salt Batch 10 Planning Program.

  19. Does small-scale vertical distribution of juvenile schooling fish affect prey availability to surface-feeding seabirds in the Wadden Sea?

    NASA Astrophysics Data System (ADS)

    Dänhardt, Andreas; Becker, Peter H.

    2011-02-01

    Food availability is a key variable influencing breeding performance and demography of marine top predators. Due to methodological problems, proportionality between fish abundance and availability is often assumed without being explicitly tested. More specifically, better breeding performance of surface-feeding seabirds at times of large prey stocks suggests that prey availability is also a function of prey abundance. Using vertically resolved stow net sampling we tested whether local abundance and length composition of pelagic fish are reliable predictors of the availability of these fish to surface-feeding Common Terns ( Sterna hirundo) breeding in the German Wadden Sea. Prey fish were found to concentrate below the maximum diving depth of the terns. Individuals caught close to the surface were in most cases smaller than conspecifics caught at greater depth. Correlations between fish abundance within and out of reach of the terns appeared to be both species- and site-specific rather than driven by overall fish abundance. Vertical distribution patterns of the terns' main prey fish could be explained as anti-predator behavior, reducing prey availability to the terns. In 2007, when breeding performance was much better than in 2006, herring and whiting were much more abundant, suggesting that overall prey abundance may also increase prey availability in habitats other than those represented by the stow net sampling.

  20. Prey capture in long-jawed butterflyfishes (Chaetodontidae): the functional basis of novel feeding habits.

    PubMed

    Ferry-Graham, L A.; Wainwright, P C.; Bellwood, D R.

    2001-01-31

    Several species of butterflyfishes (Chaetodontidae) possess extremely elongate jaws, and feed mostly by probing the benthos and biting off pieces of attached invertebrates. In contrast, Forcipiger longirostris, the longest-jawed chaetodontid, exhibits a novel pattern of prey use, feeding almost exclusively on small caridean shrimp, a mobile and highly elusive prey type that lives within the structure of coral reefs. We explored the functional basis of this novel pattern of prey use by comparing prey capture kinematics in this and four other butterflyfish species, including two other species that possess elongate jaws. High speed video recordings of feeding events on live adult brine shrimp were analyzed from individuals of five species: Forcipiger longirostris, F. flavissimus, Chelmon rostratus, Heniochus acuminatus, and Chaetodon xanthurus. We focused on a comparison among species of the relative contribution of "suction", measured as the amount of movement of the prey toward the predator's mouth, and "ram", measured as the distance moved by the predator toward the prey during the strike. All five species utilized a combination of suction and ram while feeding on brine shrimp. The contribution of suction did not differ significantly among species. However, F. longirostris exhibited a ram contribution to the strike that was more than twice that seen in any of the other species, permitting this species to initiate strikes from the greatest initial predator-prey distance. F. longirostris is known to possess a major structural novelty in the feeding mechanism that permits anterior movement of the entire jaw apparatus. The ability of this species to feed successfully on elusive prey appears to be related to exceptional jaw protrusion, resulting in greater use of ram during prey capture. This ability to protrude long, slender jaws toward the prey may allow it to move the jaws without detection within close enough proximity of the prey to then permit the effective use of

  1. Water flow controls distribution and feeding behavior of two co-occurring coral reef fishes: II. Laboratory experiments

    NASA Astrophysics Data System (ADS)

    Clarke, R. D.; Finelli, C. M.; Buskey, E. J.

    2009-06-01

    The chaenopsid blenny Acanthemblemaria spinosa occupies topographically high locations on coral reefs where flow speeds and turbulence are frequently greater than those experienced by its congener, A. aspera, which occupies locations close to the reef surface. To investigate the adaptive mechanisms resulting in this microhabitat differentiation, the foraging effort and success of these fishes were determined in laboratory flumes that produced flow conditions approximating those experienced in the field. Individual fish were subjected to unidirectional (smooth and turbulent) and oscillatory flows while they fed on calanoid copepods, Acartia tonsa, whose vulnerability to predation varies with water flow. In unidirectional flow both blenny species had their greatest foraging success at intermediate flow speeds (ca. 10 cm s-1) and under turbulent flow. Under all conditions, Acanthemblemaria spinosa exhibited greater foraging effort and attacked at greater distances, greater mean water speeds, and in oscillatory flow, over a greater proportion of the wave cycle than did A. aspera. A. spinosa also exhibited greater foraging success under turbulent flow conditions. These differences in feeding patterns allow A. spinosa, with its higher metabolic rate, to occupy the more energetic higher locations in corals where planktonic food is more abundant. A. aspera occupies the poorer quality habitat in terms of planktonic food availability but its lower metabolic rate allows it to thrive there. Consequently, these species divide the resource in short supply, i.e., shelter holes, based on their differing abilities to capture prey in energetic water conditions in conjunction with their differing food energy requirements.

  2. Spatial variations in feeding habits and trophic levels of two small pelagic fish species in the central Mediterranean Sea.

    PubMed

    Rumolo, P; Bonanno, A; Barra, M; Fanelli, E; Calabrò, M; Genovese, S; Ferreri, R; Mazzola, S; Basilone, G

    2016-04-01

    Trophic ecology of adults of European sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) was examined and compared among various regions of central Mediterranean Sea. Carbon and nitrogen stable isotope analyses (δ(13)C and δ(15)N) were adopted as a tool to determine changes in feeding behaviour of adults of sardines and anchovies. In the study period (summer) a clear geographical pattern was recognized in the isotopic composition of both species, with an increasing trend northward. The highest variations in isotopic signal were linked to the geographical positions of the samples and, especially, between pairs of areas: South Sicily/South Campania and Gulf of Gaeta/South Elba. Higher isotope values were found in the anchovies and sardines caught in northern Tyrrhenian Sea, while lower values were mostly estimated in the southern region. Higher carbon and nitrogen isotopes may reflect a more coastal behaviour of both species, being (13)C-enriched source from benthic primary producers in addition to phytoplankton. Variations in the nitrogen isotope ratio may reflect not only differences in the trophic level of prey species, but also variations in the baseline level of food webs. Our results support the hypothesis that feeding behaviour of both species is directly or indirectly influenced by local factors, or by resource partitioning based on zooplankton size. Findings can supply knowledge needed for improving fish stock management and promoting plans able to take into account also local ecosystem analysis. PMID:26895386

  3. Comparing the effects of feeding a grain- or a fish meal-based diet on water quality, waste production, and rainbow trout Oncorhynchus mykiss performance within low exchange water recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feeding a fish meal-free grain-based diet (GB) was compared to feeding a fish meal-based diet (FM) relative to water quality criteria, waste production, water treatment process performance, and rainbow trout Oncorhynchus mykiss performance within six replicated water recirculating aquaculture system...

  4. Evaluation of Enterococcus spp. from rainbow trout (Oncorhynchus mykiss, Walbaum), feed, and rearing environment against fish pathogens.

    PubMed

    Araújo, Carlos; Muñoz-Atienza, Estefanía; Hernández, Pablo E; Herranz, Carmen; Cintas, Luis M; Igrejas, Gilberto; Poeta, Patrícia

    2015-04-01

    The use of lactic acid bacteria of aquatic origin as probiotics constitutes an alternative strategy to the antibiotic treatment for disease control in aquaculture. Enterococci are currently used as probiotics in human and animal health. In this study, we evaluated the safety of 64 enterococci isolated from rainbow trout (Oncorhynchus mykiss, Walbaum), feed and rearing environment, and their antimicrobial activity against 9 fish pathogens. The 64 enterococcal isolates were identified to the species level by polymerase chain reaction (PCR), using specific primers for the different enterococcal species, and confirmed by superoxide dismutase gene sequencing. Enterococcus faecium and E. hirae were the most common species (42.2 and 35.9%, respectively). A total of 48 isolates (75%) showed phenotypic resistance to at least 1 antibiotic determined by a disk-diffusion method, and 25 isolates (39.1%) harbored at least 1 antibiotic resistance gene [erm(B), tet(M), tet(S), tet(K), tet(L), tet(T), vanC2, and aad(E)], detected by PCR. One (1.6%) isolate produced gelatinase and none produced hemolysin, using a plate assay. The virulence genes gelE (46.9%), efaAfs (17.2%), agg (1.6%), and hyl (1.6%) were detected by PCR. A total of 48 isolates (75%) exerted antimicrobial activity against 1 or more of the tested fish pathogens, using a stab-on-agar test. From these isolates, 21 (43.8%) harbored at least 1 bacteriocin-encoding gene (entP, entL50A and entL50B, hirJM79, entSE-K4, entQ and entA), detected by PCR. None of the enterococci showed bile deconjugation and mucin degradation abilities. A total of 17 enterococcal isolates (26.6%) that did not harbor any antibiotic resistance or virulence factor were considered safe for application as probiotics, including 6 isolates (35.3%) that showed antimicrobial activity against at least 1 fish pathogen and harbored at least 1 bacteriocin-encoding gene. Rainbow trout, feed, and rearing environment constitute an appropriate source for the

  5. Feeding mechanism and functional morphology of the jaws of the lemon shark Negaprion brevirostris (Chondrichthyes, Carcharhinidae)

    PubMed

    Motta; Tricas; Summers

    1997-01-01

    This study tests the hypothesis that preparatory, expansive, compressive and recovery phases of biting behavior known for aquatically feeding anamniotes are conserved among extant elasmobranch fishes. The feeding mechanism of the lemon shark Negaprionbrevirostris is examined by anatomical dissection, electromyography and high-speed video analysis. Three types of feeding events are differentiated during feeding: (1) food ingestion primarily by ram feeding; (2) food manipulation; and (3) hydraulic transport of the food by suction. All feeding events are composed of the expansive, compressive and recovery phases common to aquatically feeding teleost fishes, salamanders and turtles. A preparatory phase is occasionally observed during ingestion bites, and there is no fast opening phase characteristic of some aquatically feeding vertebrates. During the compressive phase, palatoquadrate protrusion accounts for 26% of the gape distance during jaw closure and is concurrent with muscle activity in the dorsal and ventral preorbitalis and the levator palatoquadrati. Hydraulic transport events are shorter in duration than ram ingestion bites. Prey ingestion, manipulation and hydraulic transport events are all found to have a common series of kinematic and motor components. Individual sharks are capable of varying the duration and to a lesser extent the onset of muscle activity and, consequently, can vary their biting behavior. We propose a model for the feeding mechanism in carcharhinid sharks, including upper jaw protrusion. This study represents the first electromyographic and kinematic analysis of the feeding mechanism and behavior of an elasmobranch. PMID:9326502

  6. Feeding Ecology of Predatory Fishes from Groote Eylandt in the Gulf of Carpentaria, Australia, with Special Reference to Predation on Penaeid Prawns

    NASA Astrophysics Data System (ADS)

    Brewer, D. T.; Blaber, S. J. M.; Salini, J. P.; Farmer, M. J.

    1995-05-01

    The aim of this study was to describe the feeding ecology of predatory fishes in the inshore waters of Groote Eylandt in the Gulf of Carpentaria, a large tropical bay in northern Australia. This knowledge will increase our understanding of trophic ecology of fishes in tropical waters and, in particular, their interactions with commercially important penaeid prawns. Several structurally complex habitats, including seagrass beds, mixed seagrass/reef habitats and mangrove areas, which support a diverse marine fauna, are found in these shallow waters. Consequently the diets of most predatory fishes in the region comprise a wide variety of fish and invertebrate prey. Juveniles of several species of penaeid live in seagrasses, where they are preyed on by, especially, Scomberoides commersonianusand the common shark species. However, the impact on juvenile penaeid populations is not as high as in the tropical estuaries of north-eastern Australia where fish abundances are lower. Many predatory fishes are size-selective and, in general, larger fish eat bigger penaeids. Seasonal and diel predation on penaeids is largely density-dependent. Evidence from this and previous studies indicates that individual species of tropical marine fishes eat similar prey (taxa and proportions) regardless of their habitat; any differences are chiefly only at the level of genus or species.

  7. Optimum Suction Distribution for Transition Control

    NASA Technical Reports Server (NTRS)

    Balakumar, P.; Hall, P.

    1996-01-01

    The optimum suction distribution which gives the longest laminar region for a given total suction is computed. The goal here is to provide the designer with a method to find the best suction distribution subject to some overall constraint applied to the suction. We formulate the problem using the Lagrangian multiplier method with constraints. The resulting non-linear system of equations is solved using the Newton-Raphson technique. The computations are performed for a Blasius boundary layer on a flat-plate and crossflow cases. For the Blasius boundary layer, the optimum suction distribution peaks upstream of the maximum growth rate region and remains flat in the middle before it decreases to zero at the end of the transition point. For the stationary and travelling crossflow instability, the optimum suction peaks upstream of the maximum growth rate region and decreases gradually to zero.

  8. Feed of Siamese fighting fish, Betta splendens, (Regan, 1910) in open pond: live and formulated diets.

    PubMed

    Sipaúba-Tavares, L H; Appoloni, A M; Fernandes, J B K; Millan, R N

    2016-06-01

    The growth rate and percent survival of Betta splendens when submitted to formulated diet and live food treatments are evaluated. The three different diets were used and designated as: formulated diet (basal diet); live food diet (plankton) and mixed diet (formulated diet with plankton). The live food diet contained plankton belonging to an open pond. High mortality was reported with live food (plankton) treatment whereas higher percent survival occurred with formulated diet. Highest specific growth rate, weight gain and final weight were reported in the mixed diet treatment and were significantly different (p<0.01) from those in formulated diet and live food treatments. The gut contents of B. splendens in mixed diet and live food treatments comprised, Rotifera and Bacillariophyceae species in high percentages or rather, over 78% of total organisms. Lecane sp. was the most ingested zooplankton species by B. splendens in both treatments (mixed diet and live food), with the phytoplankton species Asterionella sp. and Melosira sp. respectively in mixed diet and in live food, respectively. Results indicated that the formulated diet influenced the water parameters dissolved oxygen, total suspended solids, total dissolved solids and pH. The live food in the open pond was not enough to improve the growth rate and percent survival of B. splendens. The growth performance of B. splendens; had the best results with mixed diet which was capable of maintaining species's survival (82%) and development in artificial conditions, benefiting the culture management of ornamental fish. PMID:27097088

  9. Between-Habitat Variation of Benthic Cover, Reef Fish Assemblage and Feeding Pressure on the Benthos at the Only Atoll in South Atlantic: Rocas Atoll, NE Brazil

    PubMed Central

    Longo, G. O.; Morais, R. A.; Martins, C. D. L.; Mendes, T. C.; Aued, A. W.; Cândido, D. V.; de Oliveira, J. C.; Nunes, L. T.; Fontoura, L.; Sissini, M. N.; Teschima, M. M.; Silva, M. B.; Ramlov, F.; Gouvea, L. P.; Ferreira, C. E. L.; Segal, B.; Horta, P. A.; Floeter, S. R.

    2015-01-01

    The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most “pristine” areas in Southwestern Atlantic. We provide the first comprehensive and integrative description of the fish and benthic communities inhabiting different shallow reef habitats of Rocas. We studied two contrasting tide pool habitats: open pools, which communicate with the open ocean even during low tides, thus more exposed to wave action; and closed pools, which remain isolated during low tide and are comparatively less exposed. Reef fish assemblages, benthic cover, algal turfs and fish feeding pressure on the benthos remarkably varied between open and closed pools. The planktivore Thalassoma noronhanum was the most abundant fish species in both habitats. In terms of biomass, the lemon shark Negaprion brevirostris and the omnivore Melichtys niger were dominant in open pools, while herbivorous fishes (mainly Acanthurus spp.) prevailed in closed pools. Overall benthic cover was dominated by algal turfs, composed of articulated calcareous algae in open pools and non-calcified algae in closed pools. Feeding pressure was dominated by acanthurids and was 10-fold lower in open pools than in closed pools. Besides different wave exposure conditions, such pattern could also be related to the presence of sharks in open pools, prompting herbivorous fish to feed more in closed pools. This might indirectly affect the structure of reef fish assemblages and benthic communities. The macroalgae Digenea simplex, which is uncommon in closed pools and abundant in the reef flat, was highly preferred in herbivory assays, indicating that herbivory by fishes might be shaping this distribution pattern. The variations in benthic and reef fish communities, and feeding pressure on the benthos between open

  10. Between-Habitat Variation of Benthic Cover, Reef Fish Assemblage and Feeding Pressure on the Benthos at the Only Atoll in South Atlantic: Rocas Atoll, NE Brazil.

    PubMed

    Longo, G O; Morais, R A; Martins, C D L; Mendes, T C; Aued, A W; Cândido, D V; de Oliveira, J C; Nunes, L T; Fontoura, L; Sissini, M N; Teschima, M M; Silva, M B; Ramlov, F; Gouvea, L P; Ferreira, C E L; Segal, B; Horta, P A; Floeter, S R

    2015-01-01

    The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most "pristine" areas in Southwestern Atlantic. We provide the first comprehensive and integrative description of the fish and benthic communities inhabiting different shallow reef habitats of Rocas. We studied two contrasting tide pool habitats: open pools, which communicate with the open ocean even during low tides, thus more exposed to wave action; and closed pools, which remain isolated during low tide and are comparatively less exposed. Reef fish assemblages, benthic cover, algal turfs and fish feeding pressure on the benthos remarkably varied between open and closed pools. The planktivore Thalassoma noronhanum was the most abundant fish species in both habitats. In terms of biomass, the lemon shark Negaprion brevirostris and the omnivore Melichtys niger were dominant in open pools, while herbivorous fishes (mainly Acanthurus spp.) prevailed in closed pools. Overall benthic cover was dominated by algal turfs, composed of articulated calcareous algae in open pools and non-calcified algae in closed pools. Feeding pressure was dominated by acanthurids and was 10-fold lower in open pools than in closed pools. Besides different wave exposure conditions, such pattern could also be related to the presence of sharks in open pools, prompting herbivorous fish to feed more in closed pools. This might indirectly affect the structure of reef fish assemblages and benthic communities. The macroalgae Digenea simplex, which is uncommon in closed pools and abundant in the reef flat, was highly preferred in herbivory assays, indicating that herbivory by fishes might be shaping this distribution pattern. The variations in benthic and reef fish communities, and feeding pressure on the benthos between open and

  11. Water flow controls distribution and feeding behavior of two co-occurring coral reef fishes: I. Field measurements

    NASA Astrophysics Data System (ADS)

    Finelli, C. M.; Clarke, R. D.; Robinson, H. E.; Buskey, E. J.

    2009-06-01

    The interaction of flowing water with reef topography creates a continuum of flow microhabitats that can alter species distributions directly via transport of organisms or propagules, or indirectly by modulating the availability of critical resources. To examine how water flow affects the distribution and feeding performance of two species of planktivorous tube blennies (Chaenopsidae), flow speed and turbulence were measured within the feeding areas of Acanthemblemaria spinosa and A. aspera at three sites within Glover’s Reef, Belize. Although co-occurring, A. spinosa occupies topographically high locations (e.g., upright coral skeletons) while A. aspera occupies topographically low shelters in the coral pavement. Boundary layer theory predicts that A. spinosa should experience higher flow (and a higher flux of planktonic food) relative to A. aspera; however, complex topography and oscillatory flow require that this prediction is tested directly in the field. Within each site, the flow experienced by A. spinosa was, indeed, faster and more turbulent than that experienced by A. aspera at site-specific intermediate wave heights. When waves were small, gentle velocity gradients produced similar flows for the two species. When waves were high, flow was uniformly fast through the water column due to thinning of the benthic boundary layer. Plankton availability was similar for the species, with the exception of a greater abundance of harpacticoid copepods at the shelters of A. aspera. Quantitative behavioral observations suggest that the foraging strategies employed by the two fishes exploit the prevailing hydrodynamic conditions. For example, A. spinosa, the stronger swimmer of the two, attacks nearly 100% of the time in the water column where it can exploit the higher flux of plankton associated with faster flows, while A. aspera attacks primarily toward the reef surface where currents are likely to be slower and it can exploit more abundant benthic prey.

  12. Elemental content of commercial 'ready to-feed' poultry and fish based infant foods in the UK.

    PubMed

    Zand, Nazanin; Chowdhry, Babur Z; Wray, David S; Pullen, Frank S; Snowden, Martin J

    2012-12-15

    The study reported herein was conducted in order to establish the concentration of 20 essential and non-essential elements in a representative range of commercial infant foods in the UK targeted for infants aged between 6-12 months. The primary objective of this study was to examine the nutritive values and safety of such complementary infant foods on the UK market in relation to dietary and safety guidelines. Quantitative analyses were conducted on eight different products representing four popular brands (poultry and fish based) of ready to-feed infant foods currently on sale in the UK. Six essential elements, namely: calcium, iron, magnesium, potassium, sodium and zinc were determined by ICP-OES. The concentrations of six essential trace elements (selenium, molybdenum, cobalt, copper, chromium, manganese) and eight non-essential, potentially toxic, elements (arsenic, barium, nickel, cadmium, antimony, lead, mercury, aluminium) were determined by ICP-MS due to the higher sensitivity required. The total daily intakes of essential and trace elements from the consumption of such products were then estimated, based on the results of this study, and were referenced to the Recommended Nutrient Intake (RNI) values and safety guidelines for 6-9 months old children. Based on these comparisons the concentration of essential, except for potassium, and trace elements were found to be inadequate in meeting the RNI. In terms of the risk of exposure to toxicity, the concentration of toxic elements in ready to feed products analysed in this study, were not considered to be of concern. These results suggest that commercial complementary infant foods on the UK market may not contain minimum levels of minerals required for labelling declaration of micronutrient content (Commission Directive 2006/125/EC). This provides opportunities and scope for product optimisation to improve their nutritive value. PMID:22980874

  13. Development of thiamine deficiencies and early mortality syndrome in lake trout by feeding experimental and feral fish diets containing thiaminase

    USGS Publications Warehouse

    Honeyfield, D.C.; Hinterkopf, J.P.; Fitzsimons, J.D.; Tillitt, D.E.; Zajicek, J.L.; Brown, S.B.

    2005-01-01

    We conducted a laboratory investigation on the consequences of feeding predatory saimonids either experimental diets low in thiamine or diets containing alewife Alosa pseudoharengus. In experiment 1, adult lake trout Salvelinus namaycush were fed experimental diets containing bacterial thiaminase. In experiment 2, adult lake trout were fed natural prey species, alewives, and bloaters Coregonus hoyi. The diets consisted of four combinations of alewives and bloaters from Lake Michigan (100% alewives, 65% alewives-35% bloaters, 35% alewives-65% bloaters, and 100% bloaters), alewives from Cayuga Lake, a casein bacterial thiaminase, and a commercial trout diet. We assessed the effects of each diet on egg thiamine concentration and incidence of an embryonic early mortality syndrome (EMS). In experiment 1, incidence of EMS ranged from 0% to 100%. Significant relationships were found between the incidence of EMS and thiamine. In experiment 2, adult lake trout fed 100% alewives from either Lake Michigan or Cayuga Lake or fish fed the casein bacterial thiaminase diet produced eggs with low thiamine and swim-up fry with EMS. At either 35% or 65% alewives in the diet, egg thiamine was significantly lowered. The number of females that produced offspring that died from EMS were low but demonstrated the negative potential if feral lake trout foraged on either 35% or 65% alewives. Depleted egg thiamine and the onset of EMS required diets containing thiaminase for a minimum of 2 years in lake trout initially fully thiamine replete. We conclude that EMS can be caused by extensive feeding on 100% alewives and dietary levels of 35% or greater may prove detrimental to sustainable reproduction of salmonids in the Great Lakes. The data are consistent with that observed in feral lake trout, and it is concluded that EMS is the result of a thiamine deficiency. ?? Copyright by the American Fisheries Society 2005.

  14. Experiments with suction-type wings

    NASA Technical Reports Server (NTRS)

    Schrenk, O

    1935-01-01

    The present report collects the investigations of the past years which, while not as yet intended for use in construction, show different possibilities for the building of a suction-type wing and at the same time present some basic explanations concerning the problem of suction. Experiments and results with a thick wing profile are detailed as well as boundary layer removal by suction and sink action. Experiments with flap profiles are also included.

  15. You are what you eat: diet-induced chemical crypsis in a coral-feeding reef fish

    PubMed Central

    Brooker, Rohan M.; Munday, Philip L.; Chivers, Douglas P.; Jones, Geoffrey P.

    2015-01-01

    The vast majority of research into the mechanisms of camouflage has focused on forms that confound visual perception. However, many organisms primarily interact with their surroundings using chemosensory systems and may have evolved mechanisms to ‘blend in’ with chemical components of their habitat. One potential mechanism is ‘chemical crypsis' via the sequestration of dietary elements, causing a consumer's odour to chemically match that of its prey. Here, we test the potential for chemical crypsis in the coral-feeding filefish, Oxymonacanthus longirostris, by examining olfactory discrimination in obligate coral-dwelling crabs and a predatory cod. The crabs, which inhabit the corals consumed by O. longirostris, were used as a bioassay to determine the effect of coral diet on fish odour. Crabs preferred the odour of filefish fed their preferred coral over the odour of filefish fed a non-preferred coral, suggesting coral-specific dietary elements that influence odour are sequestered. Crabs also exhibited a similar preference for the odour of filefish fed their preferred coral and odour directly from that coral, suggesting a close chemical match. In behavioural trials, predatory cod were less attracted to filefish odour when presented alongside the coral it had been fed on, suggesting diet can reduce detectability. This is, we believe, the first evidence of diet-induced chemical crypsis in a vertebrate. PMID:25621328

  16. Temperature acclimation rate of aerobic scope and feeding metabolism in fishes: implications in a thermally extreme future.

    PubMed

    Sandblom, Erik; Gräns, Albin; Axelsson, Michael; Seth, Henrik

    2014-11-01

    Temperature acclimation may offset the increased energy expenditure (standard metabolic rate, SMR) and reduced scope for activity (aerobic scope, AS) predicted to occur with local and global warming in fishes and other ectotherms. Yet, the time course and mechanisms of this process is little understood. Acclimation dynamics of SMR, maximum metabolic rate, AS and the specific dynamic action of feeding (SDA) were determined in shorthorn sculpin (Myoxocephalus scorpius) after transfer from 10°C to 16°C. SMR increased in the first week by 82% reducing AS to 55% of initial values, while peak postprandial metabolism was initially greater. This meant that the estimated AS during peak SDA approached zero, constraining digestion and leaving little room for additional aerobic processes. After eight weeks at 16°C, SMR was restored, while AS and the estimated AS during peak SDA recovered partly. Collectively, this demonstrated a considerable capacity for metabolic thermal compensation, which should be better incorporated into future models on organismal responses to climate change. A mathematical model based on the empirical data suggested that phenotypes with fast acclimation rates may be favoured by natural selection as the accumulated energetic cost of a slow acclimation rate increases in a warmer future with exacerbated thermal variations. PMID:25232133

  17. Jaw muscle fiber type distribution in Hawaiian gobioid stream fishes: histochemical correlations with feeding ecology and behavior.

    PubMed

    Maie, Takashi; Meister, Andrew B; Leonard, Gerald L; Schrank, Gordon D; Blob, Richard W; Schoenfuss, Heiko L

    2011-12-01

    Differences in fiber type distribution in the axial muscles of Hawaiian gobioid stream fishes have previously been linked to differences in locomotor performance, behavior, and diet across species. Using ATPase assays, we examined fiber types of the jaw opening sternohyoideus muscle across five species, as well as fiber types of three jaw closing muscles (adductor mandibulae A1, A2, and A3). The jaw muscles of some species of Hawaiian stream gobies contained substantial red fiber components. Some jaw muscles always had greater proportions of white muscle fibers than other jaw muscles, independent of species. In addition, comparing across species, the dietary generalists (Awaous guamensis and Stenogobius hawaiiensis) had a lower proportion of white muscle fibers in all jaw muscles than the dietary specialists (Lentipes concolor, Sicyopterus stimpsoni, and Eleotris sandwicensis). Among Hawaiian stream gobies, generalist diets may favor a wider range of muscle performance, provided by a mix of white and red muscle fibers, than is typical of dietary specialists, which may have a higher proportion of fast-twitch white fibers in jaw muscles to help meet the demands of rapid predatory strikes or feeding in fast-flowing habitats. PMID:21978841

  18. Nano-Fe as feed additive improves the hematological and immunological parameters of fish, Labeo rohita H.

    NASA Astrophysics Data System (ADS)

    Behera, T.; Swain, P.; Rangacharulu, P. V.; Samanta, M.

    2014-08-01

    An experiment was conducted to compare the effects of iron oxide nanoparticles ( T 1) and ferrous sulfate ( T 2) on Indian major carp, Labeo rohita H. There were significant differences ( P < 0.05) in the final weight of T 1 and T 2 compared with the control. Survival rates were not affected by the dietary treatments. Fish fed a basal diet (control) showed lower ( P < 0.05) iron content in muscle compared to T 1 and T 2. Furthermore, the highest value ( P < 0.05) of iron content was observed in T 1. In addition, RBCs and hemoglobin levels were significantly higher in T 1 as compared to other treated groups. Different innate immune parameters such as respiratory burst activity, bactericidal activity and myeloperoxidase activity were higher in nano-Fe-treated diet ( T 1) as compared to other iron source ( T 2) and control in 30 days post-feeding. Moreover, nano-Fe appeared to be more effective ( P < 0.05) than ferrous sulfate in increasing muscle iron and hemoglobin contents. Dietary administration of nano-Fe did not cause any oxidative damage, but improved antioxidant enzymatic activities (SOD and GSH level) irrespective of different iron sources in the basal diet.

  19. FAST Real Time PCR for control of intra-species recycling in aquaculture feed, focused to the most relevant fish species farmed in Europe.

    PubMed

    Espiñeira, Montserrat; Vieites, Juan M

    2016-08-01

    Recent regulations in animal feed composition prohibit intra-species recycling, the recycling of one given animal species to the same species, in order to avoid potential safety risks to human and animal health. These regulations have generated the need of their control in aquaculture by effective and specific analytical techniques. To date, most studies of species identification and detection in feedstuffs are focused on land species, but few studies are focused on species composition in fish feed. The present work describes five methodologies based in Real Time PCR for detection of the most relevant fish species farmed in Europe: gilthead sea bream (Sparus aurata); sea bass (Dicentrarchus labrax); turbot (Scophthalmus maximus); rainbow trout (Onchorynchus mykiss); and salmon (Salmo salar), in order to guarantee the intra-species recycling regulation in aquaculture feedstuffs. PMID:26988512

  20. Feeding a Modified Fish Diet to Bottlenose Dolphins Leads to an Increase in Serum Adiponectin and Sphingolipids.

    PubMed

    Sobolesky, Philip M; Harrell, Tyler S; Parry, Celeste; Venn-Watson, Stephanie; Janech, Michael G

    2016-01-01

    Feeding a modified fish diet has been suggested to improve insulin sensitivity in bottlenose dolphins; however, insulin sensitivity was not directly measured. Since demonstrating an improvement in insulin sensitivity is technically difficult in dolphins, we postulated that directional changes in the hormone axis: fibroblast growth factor 21 (FGF21)/Adiponectin/Ceramide (Cer), could provide further support to this hypothesis. We measured 2-h post-prandial serum FGF21, total adiponectin, percent unmodified adiponectin, ceramide, and sphingosine levels from dolphins fed a diet rich in heptadecanoic acid (C17:0) over 24 weeks. Serum FGF21 was quantified by ELISA with an observed range of 129-1599 pg/ml, but did not significantly change over the 24-week study period. Total adiponectin levels (mean ± SD) significantly increased from 776 ± 400 pmol/ml at week 0 to 1196 ± 467 pmol/ml at week 24. The percent unmodified adiponectin levels (mean ± SD) decreased from 23.8 ± 6.0% at week 0 to 15.2 ± 5.2% at week 24. Interestingly, although FGF21 levels did not change, there was a good correlation between FGF21 and total adiponectin (ρ = 0.788, P < 0.001). We quantified the abundances of serum ceramides and sphingosines (SPH) because adiponectin has a defined role in sphingolipid metabolism through adiponectin receptor-mediated activation of ceramidases. The most abundant ceramide in dolphin sera was Cer 24:1 comprising 49% of the ceramides measured. Significant reductions were observed in the unsaturated Cer 18:1, Cer 20:1, and Cer 24:1, whereas significant increases were observed in saturated Cer 22:0, Cer 24:0, and Cer 26:0. However, total serum ceramides did not change. Significant elevations were detected for total sphingosine, dihydrosphingosine, sphingosine-1-phosphate, and dihydrosphingosine-1-phosphate. Proteomic analysis of the serum proteins revealed few changes in serum proteins over the study period. In conclusion

  1. Feeding a Modified Fish Diet to Bottlenose Dolphins Leads to an Increase in Serum Adiponectin and Sphingolipids

    PubMed Central

    Sobolesky, Philip M.; Harrell, Tyler S.; Parry, Celeste; Venn-Watson, Stephanie; Janech, Michael G.

    2016-01-01

    Feeding a modified fish diet has been suggested to improve insulin sensitivity in bottlenose dolphins; however, insulin sensitivity was not directly measured. Since demonstrating an improvement in insulin sensitivity is technically difficult in dolphins, we postulated that directional changes in the hormone axis: fibroblast growth factor 21 (FGF21)/Adiponectin/Ceramide (Cer), could provide further support to this hypothesis. We measured 2-h post-prandial serum FGF21, total adiponectin, percent unmodified adiponectin, ceramide, and sphingosine levels from dolphins fed a diet rich in heptadecanoic acid (C17:0) over 24 weeks. Serum FGF21 was quantified by ELISA with an observed range of 129–1599 pg/ml, but did not significantly change over the 24-week study period. Total adiponectin levels (mean ± SD) significantly increased from 776 ± 400 pmol/ml at week 0 to 1196 ± 467 pmol/ml at week 24. The percent unmodified adiponectin levels (mean ± SD) decreased from 23.8 ± 6.0% at week 0 to 15.2 ± 5.2% at week 24. Interestingly, although FGF21 levels did not change, there was a good correlation between FGF21 and total adiponectin (ρ = 0.788, P < 0.001). We quantified the abundances of serum ceramides and sphingosines (SPH) because adiponectin has a defined role in sphingolipid metabolism through adiponectin receptor-mediated activation of ceramidases. The most abundant ceramide in dolphin sera was Cer 24:1 comprising 49% of the ceramides measured. Significant reductions were observed in the unsaturated Cer 18:1, Cer 20:1, and Cer 24:1, whereas significant increases were observed in saturated Cer 22:0, Cer 24:0, and Cer 26:0. However, total serum ceramides did not change. Significant elevations were detected for total sphingosine, dihydrosphingosine, sphingosine-1-phosphate, and dihydrosphingosine-1-phosphate. Proteomic analysis of the serum proteins revealed few changes in serum proteins over the study period. In conclusion

  2. Effects of Feeding Diets With or Without Fish Meal on Production of Channel Catfish, Ictalurus Punctatus, Stocked at Varying Densities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal protein, generally fish meal, has traditionally been used in the diet of channel catfish. However, our previous research indicates that animal protein is not needed for growing stocker size catfish to food fish when the fish are stocked at densities typical of those used in commercial catfish...

  3. Evolutionary Novelty versus Exaptation: Oral Kinematics in Feeding versus Climbing in the Waterfall-Climbing Hawaiian Goby Sicyopterus stimpsoni

    PubMed Central

    Cullen, Joshua A.; Maie, Takashi; Schoenfuss, Heiko L.; Blob, Richard W.

    2013-01-01

    Species exposed to extreme environments often exhibit distinctive traits that help meet the demands of such habitats. Such traits could evolve independently, but under intense selective pressures of extreme environments some existing structures or behaviors might be coopted to meet specialized demands, evolving via the process of exaptation. We evaluated the potential for exaptation to have operated in the evolution of novel behaviors of the waterfall-climbing gobiid fish genus Sicyopterus. These fish use an “inching” behavior to climb waterfalls, in which an oral sucker is cyclically protruded and attached to the climbing surface. They also exhibit a distinctive feeding behavior, in which the premaxilla is cyclically protruded to scrape diatoms from the substrate. Given the similarity of these patterns, we hypothesized that one might have been coopted from the other. To evaluate this, we filmed climbing and feeding in Sicyopterus stimpsoni from Hawai’i, and measured oral kinematics for two comparisons. First, we compared feeding kinematics of S. stimpsoni with those for two suction feeding gobiids (Awaous guamensis and Lentipes concolor), assessing what novel jaw movements were required for algal grazing. Second, we quantified the similarity of oral kinematics between feeding and climbing in S. stimpsoni, evaluating the potential for either to represent an exaptation from the other. Premaxillary movements showed the greatest differences between scraping and suction feeding taxa. Between feeding and climbing, overall profiles of oral kinematics matched closely for most variables in S. stimpsoni, with only a few showing significant differences in maximum values. Although current data cannot resolve whether oral movements for climbing were coopted from feeding, or feeding movements coopted from climbing, similarities between feeding and climbing kinematics in S. stimpsoni are consistent with evidence of exaptation, with modifications, between these behaviors

  4. Evolutionary novelty versus exaptation: oral kinematics in feeding versus climbing in the waterfall-climbing Hawaiian Goby Sicyopterus stimpsoni.

    PubMed

    Cullen, Joshua A; Maie, Takashi; Schoenfuss, Heiko L; Blob, Richard W

    2013-01-01

    Species exposed to extreme environments often exhibit distinctive traits that help meet the demands of such habitats. Such traits could evolve independently, but under intense selective pressures of extreme environments some existing structures or behaviors might be coopted to meet specialized demands, evolving via the process of exaptation. We evaluated the potential for exaptation to have operated in the evolution of novel behaviors of the waterfall-climbing gobiid fish genus Sicyopterus. These fish use an "inching" behavior to climb waterfalls, in which an oral sucker is cyclically protruded and attached to the climbing surface. They also exhibit a distinctive feeding behavior, in which the premaxilla is cyclically protruded to scrape diatoms from the substrate. Given the similarity of these patterns, we hypothesized that one might have been coopted from the other. To evaluate this, we filmed climbing and feeding in Sicyopterus stimpsoni from Hawai'i, and measured oral kinematics for two comparisons. First, we compared feeding kinematics of S. stimpsoni with those for two suction feeding gobiids (Awaous guamensis and Lentipes concolor), assessing what novel jaw movements were required for algal grazing. Second, we quantified the similarity of oral kinematics between feeding and climbing in S. stimpsoni, evaluating the potential for either to represent an exaptation from the other. Premaxillary movements showed the greatest differences between scraping and suction feeding taxa. Between feeding and climbing, overall profiles of oral kinematics matched closely for most variables in S. stimpsoni, with only a few showing significant differences in maximum values. Although current data cannot resolve whether oral movements for climbing were coopted from feeding, or feeding movements coopted from climbing, similarities between feeding and climbing kinematics in S. stimpsoni are consistent with evidence of exaptation, with modifications, between these behaviors. Such

  5. How to suction via a tracheostomy.

    PubMed

    Credland, Nicola

    2016-03-01

    Rationale and key points Patients with a tracheostomy tube may be unable to cough adequately to expel pulmonary secretions. Therefore, tracheal suction is essential in managing secretions and maintaining respiratory function and a patent airway. Tracheal suction reduces the risk of consolidation and atelectasis that may lead to inadequate ventilation. ▶ Respiratory assessment of the patient should be carried out to identify when tracheal suction is required. ▶ A suction pressure of 80-120mmHg is recommended, and suction should last no longer than 15 seconds. ▶ Reassurance and support should be given to the patient to minimise any discomfort and distress that may result from tracheal suction. Reflective activity Clinical skills articles can help update your practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. How you think this article will change your practice when performing tracheal suction. 2. How you could use this resource to educate your colleagues. Subscribers can upload their reflective accounts at: rcni.com/portfolio . PMID:26959470

  6. Sudden weaning of angel fish pterophyllum scalare (Lichtenstein) (Pisces; Cichlidae) larvae from brine shrimp (Artemia sp) nauplii to formulated larval feed.

    PubMed

    Herath, Sandamali Sakunthala; Atapaththu, Kerthi Sri Senarathna

    2013-12-01

    This study investigated the effects of sudden weaning of angel fish larvae (Pteraphylum scalari) from Artemia nauplii to commercial larval feed. Four days post hatch (DPH) larvae were reared in four different weaning protocols (TR1-TR4) with triplicates in a complete randomize design. Larvae in TR1 and TR4 were exclusively fed Artemia nauplii and dry feed respectively. In TR2 and TR3, larvae were initially fed Artemia nauplii and suddenly wean to formulated feed on 14 DPH and 7 DPH respectively. The experiment was lasted for 28 days. At the end of the experiment, final mean weight (FW), total length (FL), height (FH), Daily Weight Gain (DWG), Specific Growth Rate (SGR), survival and stress index were compared. Significantly highest (P < 0.05) FW, DWG and SGR were observed in TR1 and TR2 while former values of TR3 were not significantly different from TR1. Highest FL observed in TR1 and TR2 while FL of TR2 was statistically similar to that of TR3. The poorest growth was observed in larvae solely fed formulated feed. Survival and the stress index were independent from weaning methods. Although sudden weaning is possible on 7 DPH, larvae showed comparatively higher growth when switch off to formulate feed on 14 DPH. PMID:23626927

  7. Use of food waste as fish feeds: effects of prebiotic fibers (inulin and mannanoligosaccharide) on growth and non-specific immunity of grass carp (Ctenopharyngodon idella).

    PubMed

    Mo, Wing Y; Cheng, Zhang; Choi, Wai M; Lun, Clare H I; Man, Yu B; Wong, James T F; Chen, Xun W; Lau, Stanley C K; Wong, Ming H

    2015-11-01

    The effects of inulin and mannanoligosaccharide (MOS) on the growth performance and non-specific immunity of grass carp were studied. Two doses of prebiotic fiber with 0.2 or 2% of the fibers are being mixed into fish feed pellets. Fish growth as well as selected non-specific immune parameters of grass carp were tested in a feeding trial, which lasted for 8 weeks. Fish was fed at 2.5% body mass per day. INU02, INU2, and MOS2 significantly improved relative weight gain, specific growth rate, protein efficiency ratio, and food conversion ratio of grass carp fed with food waste-based diet. In terms of non-specific immune response, grass carp showed significant improvement in all three tested parameters (total serum immunoglobin, bactericidal activity, and anti-protease activity). Adding 2% of inulin (INU2) into food waste diets seemed to be more preferable than other supplemented experimental diets (INU02, MOS02, MOS2), as it could promote growth of grass carp as well as improving the non-specific immune systems of grass carp. PMID:26150295

  8. Are parasite richness and abundance linked to prey species richness and individual feeding preferences in fish hosts?

    PubMed

    Cirtwill, Alyssa R; Stouffer, Daniel B; Poulin, Robert; Lagrue, Clément

    2016-01-01

    Variations in levels of parasitism among individuals in a population of hosts underpin the importance of parasites as an evolutionary or ecological force. Factors influencing parasite richness (number of parasite species) and load (abundance and biomass) at the individual host level ultimately form the basis of parasite infection patterns. In fish, diet range (number of prey taxa consumed) and prey selectivity (proportion of a particular prey taxon in the diet) have been shown to influence parasite infection levels. However, fish diet is most often characterized at the species or fish population level, thus ignoring variation among conspecific individuals and its potential effects on infection patterns among individuals. Here, we examined parasite infections and stomach contents of New Zealand freshwater fish at the individual level. We tested for potential links between the richness, abundance and biomass of helminth parasites and the diet range and prey selectivity of individual fish hosts. There was no obvious link between individual fish host diet and helminth infection levels. Our results were consistent across multiple fish host and parasite species and contrast with those of earlier studies in which fish diet and parasite infection were linked, hinting at a true disconnect between host diet and measures of parasite infections in our study systems. This absence of relationship between host diet and infection levels may be due to the relatively low richness of freshwater helminth parasites in New Zealand and high host-parasite specificity. PMID:26573385

  9. Reproduction and Feeding of the Electric Fish Brachyhypopomus gauderio (Gymnotiformes: Hypopomidae) and the Discussion of a Life History Pattern for Gymnotiforms from High Latitudes

    PubMed Central

    Giora, Julia; Tarasconi, Hellen M.; Fialho, Clarice B.

    2014-01-01

    The reproductive biology and feeding habits of the electric fish Brachyhypopomus gauderio were studied. The species has seasonal reproductive behavior, with breeding occurring during the Southern Hemisphere spring and summer, and having a positive relation with the photoperiod variation. Brachyhypopomus gauderio was defined as a fractional spawner, with low relative fecundity and high first maturation size. Sexual dimorphism was registered, males undergoing hypertrophy of the distal portion of caudal filament. The results on reproductive biology herein obtained are in agreement with data concerning gymnotiforms from Southern Brazil and Uruguay, pointing to an ecological pattern for the species from high latitudes, differing from species with tropical distribution. According to the analysis of the food items, B. gauderio feed mainly on autochthonous insects, likewise the other gymnotiforms previously investigated, leading to conclude that there is no variation on the diet of the species of the order related to climatic conditions or even to habitat of occurrence. PMID:25207924

  10. Feeding of the megamouth shark (Pisces: Lamniformes: Megachasmidae) predicted by its hyoid arch: a biomechanical approach.

    PubMed

    Tomita, Taketeru; Sato, Keiichi; Suda, Kenta; Kawauchi, Junro; Nakaya, Kazuhiro

    2011-05-01

    Studies of the megamouth shark, one of three planktivorous sharks, can provide information about their evolutionary history. Megamouth shark feeding has never been observed in life animals, but two alternative hypotheses on biomechanics suggest either feeding, i.e., ram feeding or suction feeding. In this study, the second moment of area of the ceratohyal cartilages, which is an indicator of the flexural stiffness of the cartilages, is calculated for 21 species of ram- and suction-feeding sharks using computed tomography. The results indicate that suction-feeding sharks have ceratohyal cartilages with a larger second moment of area than ram-feeding sharks. The result also indicates that the ram-suction index, which is an indicator of relative contribution of ram and suction behavior, is also correlated with the second moment of area of the ceratohyal. Considering that large bending stresses are expected to be applied to the ceratohyal cartilage during suction, the larger second moment of area of the ceratohyal of suction-feeding sharks can be interpreted as an adaptation for suction feeding. Based on the small second moment of area of the ceratohyal cartilage of the megamouth shark, the feeding mode of the megamouth shark is considered to be ram feeding, similar to the planktivorous basking shark. From these results, an evolutionary scenario of feeding mechanics of three species of planktivorous sharks can be suggested. In this scenario, the planktivorous whale shark evolved ram feeding from a benthic suction-feeding ancestor. Ram feeding in the planktivorous megamouth shark and the basking shark evolved from ram feeding swimming-type ancestors and that both developed their unique filtering system to capture small-sized prey. PMID:21381075

  11. Thermophile-fermented compost as a fish feed additive modulates lipid peroxidation and free amino acid contents in the muscle of the carp, Cyprinus carpio.

    PubMed

    Tanaka, Ryusuke; Miyamoto, Hirokuni; Inoue, Shin-Ichi; Shigeta, Kazuhiro; Kondo, Masakazu; Ito, Toshiyuki; Kodama, Hiroaki; Miyamoto, Hisashi; Matsushita, Teruo

    2016-05-01

    Recently, a compost fermented with marine animals with thermophilic Bacillaceae in a clean and exclusive process at high temperature was reported as a possible feed additive to improve the healthy balance in sea fish and mammals (i.e., pigs and rodents). Here, the effects of the oral administration of the compost on the muscle and internal organs of carp (Cyprinus carpio) as a freshwater fish model were investigated. The fatty acid composition was different in the muscle of the carp fed with or without the compost extract, but there was little difference in the hepatopancreas. The accumulation of triacylglycerols, cholesterol, lipid peroxide and hydroxyl lipids decreased in the muscle after the oral administration of the compost extract in the carps over 12 weeks, but the accumulation did not always decrease in the hepatopancreas. In contrast, free-radical-scavenging activities and the concentrations of free amino acids in the muscle did not always increase and was dependent on the dose of the compost at 12 weeks. The scavenging activities and part of free amino acid levels in the muscle of the carp were improved at 24 weeks after a high dose of compost exposure, and then the survival rates of the carp were maintained. Thus, the oral administration of thermophile-fermented compost can prevent peroxidation and increase the content of free amino acids in the muscle of the freshwater fish, depending on the dose and term of the administration, and may be associated with the viability of the fish. PMID:26702954

  12. Confocal microscopy as a useful approach to describe gill rakers of Asian species of carp and native filter-feeding fishes of the upper Mississippi River system

    USGS Publications Warehouse

    Liza R. Walleser; D.R. Howard; Sandheinrich, Mark B.; Gaikowski, Mark P.; Amberg, Jon J.

    2014-01-01

    To better understand potential diet overlap among exotic Asian species of carp and native species of filter-feeding fishes of the upper Mississippi River system, microscopy was used to document morphological differences in the gill rakers. Analysing samples first with light microscopy and subsequently with confocal microscopy, the three-dimensional structure of gill rakers in Hypophthalmichthys molitrix,Hypophthalmichthys nobilis and Dorosoma cepedianum was more thoroughly described and illustrated than previous work with traditional microscopy techniques. The three-dimensional structure of gill rakers in Ictiobus cyprinellus was described and illustrated for the first time.

  13. Effects of brown fish meal replacement with fermented soybean meal on growth performance, feed efficiency and enzyme activities of Chinese soft-shelled turtle, Pelodiscus sinensis

    NASA Astrophysics Data System (ADS)

    Zou, Yurong; Ai, Qinghui; Mai, Kangsen; Zhang, Wenbing; Zhang, Yanjiao; Xu, Wei

    2012-06-01

    A 120-day feeding experiment was conducted to investigate the effects of partial replacement of brown fish meal (BFM) by fermented soybean meal (FSBM) in diets of Chinese soft-shelled turtle ( Pelodiscus sinensis). The turtles (initial mean body weight, (115.52 ± 1.05) g) were fed with three experimental diets, in which 0%, 4.72% and 9.44% BFM protein was replaced by 0%, 3% and 6% FSBM, respectively. Results showed that the feeding rate (FR), specific growth rate (SGR) and feed efficiency ratio (FER) of turtles fed with the diet containing 3% FSBM were not significantly different from the control group (0% FSBM) ( P > 0.05). However, FR, SGR and FER of turtles fed with the diet containing 6% FSBM were significantly lower than those of the control group ( P < 0.05). No significant differences were observed in the activities of serum glutamic-oxalacetic transaminase and glutamic-pyruvic transaminase among dietary treatments ( P > 0.05). However, the uric acid concentration in turtles fed with the diet containing 3% or 6% FSBM was significantly lower than that in the control group ( P < 0.05). There were no significant differences in the activities of lysozyme, alkaline phosphatase and total superoxide dismutase among dietary treatments ( P > 0.05). The results suggested that FSBM could replace 4.72% BFM protein in turtle diets without exerting adverse effects on turtle growth, feed utilization and measured immune parameters.

  14. Trophic ecology of the deep-sea fish Malacosteus niger (Pisces: Stomiidae): An enigmatic feeding ecology to facilitate a unique visual system?

    NASA Astrophysics Data System (ADS)

    Sutton, Tracey T.

    2005-11-01

    The deep-sea fish Malacosteus niger belongs to a family of fishes, the dragonfishes (Order: Stomiiformes, Family: Stomiidae), that are among the top predators of the open ocean mesopelagic zone. Malacosteus typifies the morphological adaptation of this group for the taking of relatively large prey. These adaptations include huge fangs, an enormous gape, and the loss of gill rakers. Despite these adaptations, examination of specimens of this species from different ocean basins shows that zooplanktivory is a common feeding mode of the species, an extreme departure from its trophic lineage. Large calanoid copepods made up 69-83% of prey numbers and 9-47% of prey biomass in specimens from the North Atlantic, the Gulf of Mexico, and throughout the Pacific. As M. niger feeding observations have never been reported, the rationale for this enigmatic feeding ecology must be inferred from other aspects of its ecology. As presently known, M. niger is unique among all vertebrates in the possession of both a long-wave bioluminescence system and a bacteriochlorophyll-derived retinal photosensitizer that allows long-wave visual sensitivity. A two-part theory is presented to explain why M. niger radically diverges from its clade and preys on food it does not appear morphologically suited to eat: (1) the combination of long-wave bioluminescence and vision systems suggests that M. niger may search small volumes for food, and thus may sustain itself energetically by snacking on small parcels of food (copepods) in between rare encounters with large prey, and (2) M. niger may gain the raw material for its long-wave visual sensitivity, and thus its feeding mode, from the consumption of copepods.

  15. Microbial contamination of suction tubes attached to suction instruments and preventive methods.

    PubMed

    Yorioka, Katsuhiro; Oie, Shigeharu; Kamiya, Akira

    2010-03-01

    We investigated the microbial contamination of suction tubes attached to wall-type suction instruments. Microbial contamination of suction tubes used for endoscopy or sputum suction in hospital wards was examined before and after their disinfection. In addition, disinfection and washing methods for suction tubes were evaluated. Suction tubes (n=33) before disinfection were contaminated with 10(2)-10(8) colony-forming units (cfu)/tube. The main contaminants were Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia. The suction tubes were disinfected with sodium hypochlorite (n=11) or hot water (n=11), or by an automatic tube cleaner (n=11). After 2-h immersion in 0.1% (1,000 ppm) sodium hypochlorite, 10(3)-10(7) cfu/tube of bacteria were detected in all 11 tubes examined. After washing in hot running water (65 degrees C), 10(3)-10(7) cfu/tube were detected in 3 of the 11 examined tubes. The bacteria detected in the suction tubes after disinfection with sodium hypochlorite or hot water were P. aeruginosa, A. baumannii, and S. maltophilia. On the other hand, after washing with warm water (40 degrees C) using the automatic tube cleaner, contamination was found to be <20 cfu/tube (lower detection limit, 20 cfu/tube) in all 11 tubes examined. These results suggest the usefulness of washing with automatic tube cleaners. PMID:20332576

  16. Automated detection of feeding strikes by larval fish using continuous high-speed digital video: a novel method to extract quantitative data from fast, sparse kinematic events.

    PubMed

    Shamur, Eyal; Zilka, Miri; Hassner, Tal; China, Victor; Liberzon, Alex; Holzman, Roi

    2016-06-01

    Using videography to extract quantitative data on animal movement and kinematics constitutes a major tool in biomechanics and behavioral ecology. Advanced recording technologies now enable acquisition of long video sequences encompassing sparse and unpredictable events. Although such events may be ecologically important, analysis of sparse data can be extremely time-consuming and potentially biased; data quality is often strongly dependent on the training level of the observer and subject to contamination by observer-dependent biases. These constraints often limit our ability to study animal performance and fitness. Using long videos of foraging fish larvae, we provide a framework for the automated detection of prey acquisition strikes, a behavior that is infrequent yet critical for larval survival. We compared the performance of four video descriptors and their combinations against manually identified feeding events. For our data, the best single descriptor provided a classification accuracy of 77-95% and detection accuracy of 88-98%, depending on fish species and size. Using a combination of descriptors improved the accuracy of classification by ∼2%, but did not improve detection accuracy. Our results indicate that the effort required by an expert to manually label videos can be greatly reduced to examining only the potential feeding detections in order to filter false detections. Thus, using automated descriptors reduces the amount of manual work needed to identify events of interest from weeks to hours, enabling the assembly of an unbiased large dataset of ecologically relevant behaviors. PMID:26994179

  17. Effect of feeding lipids recovered from fish processing waste by lactic acid fermentation and enzymatic hydrolysis on antioxidant and membrane bound enzymes in rats.

    PubMed

    Rai, Amit Kumar; Bhaskar, N; Baskaran, V

    2015-06-01

    Fish oil recovered from fresh water fish visceral waste (FVW-FO) through lactic acid fermentation (FO-LAF) and enzymatic hydrolysis (FO-EH) were fed to rats to study their influence on lipid peroxidation and activities of antioxidant and membrane bound enzyme in liver, heart and brain. Feeding of FO-LAF and FO-EH resulted in increase (P < 0.05) in lipid peroxides level in serum, liver, brain and heart tissues compared to ground nut oil (control). Activity of catalase (40-235 %) and superoxide dismutase (17-143 %) also increased (P < 0.05) with incremental level of EPA + DHA in diet. The increase was similar to cod liver oil fed rats at same concentration of EPA + DHA. FO-LAF and FO-EH increased (P < 0.05) the Na(+)K(+) ATPase activity in liver and brain microsomes, Ca(+)Mg(+) ATPase in heart microsome and acetylcholine esterase in brain microsomes when fed with 5 % EPA + DHA. There was also significant change in fatty acid composition and cholesterol/phospholipid ratio in microsomes of rat fed with FVW-FO. Feeding FVW-FO recovered by biotechnological approaches enhanced the activity of antioxidant enzymes in tissues, modulates the activities of membrane bound enzymes and improved the fatty acid composition in microsomes of tissues similar to CLO. Utilization of these processing wastes for the production of valuable biofunctional products can reduce the mounting economic values of fish oil and minimize the environmental pollution problems. PMID:26028754

  18. Compressible laminar streaks with wall suction

    NASA Astrophysics Data System (ADS)

    Ricco, Pierre; Shah, Daniel; Hicks, Peter D.

    2013-05-01

    The response of a compressible laminar boundary layer subject to free-stream vortical disturbances and steady mean-flow wall suction is studied. The theoretical frameworks of Leib et al. [J. Fluid Mech. 380, 169-203 (1999), 10.1017/S0022112098003504] and Ricco and Wu [J. Fluid Mech. 587, 97-138 (2007), 10.1017/S0022112007007070], based on the linearized unsteady boundary-region equations, are adopted to study the influence of suction on the kinematic and thermal streaks arising through the interaction between the free-stream vortical perturbations and the boundary layer. In the asymptotic limit of small spanwise wavelength compared with the boundary layer thickness, i.e., when the disturbance flow is conveniently described by the steady compressible boundary region equations, the effect of suction is mild on the velocity fluctuations and negligible on the temperature fluctuations. When the spanwise wavelength is comparable with the boundary layer thickness, small suction values intensify the supersonic streaks, while higher transpiration levels always stabilize the disturbances at all Mach numbers. At larger spanwise wavelengths, very small amplitudes of wall transpiration have a dramatic stabilizing effect on all boundary layer fluctuations, which can take the form of transiently growing thermal streaks, large amplitude streamwise oscillations, or oblique exponentially growing Tollmien-Schlichting waves, depending on the Mach number and the wavelengths. The range of wavenumbers for which the exponential growth occurs becomes narrower and the location of instability is significantly shifted downstream by mild suction, indicating that wall transpiration can be a suitable vehicle for delaying transition when the laminar breakdown is promoted by these unstable disturbances. The typical streamwise wavelength of these disturbances is instead not influenced by suction, and asymptotic triple deck theory predicts the strong changes in growth rate and the very mild

  19. Falling liquid films with blowing and suction

    NASA Astrophysics Data System (ADS)

    Thompson, Alice B.; Tseluiko, Dmitri; Papageorgiou, Demetrios T.

    2016-01-01

    Flow of a thin viscous film down a flat inclined plane becomes unstable to long wave interfacial fluctuations when the Reynolds number based on the mean film thickness becomes larger than a critical value (this value decreases as the angle of inclination with the horizontal increases, and in particular becomes zero when the plate is vertical). Control of these interfacial instabilities is relevant to a wide range of industrial applications including coating processes and heat or mass transfer systems. This study considers the effect of blowing and suction through the substrate in order to construct from first principles physically realistic models that can be used for detailed passive and active control studies of direct relevance to possible experiments. Two different long-wave, thin-film equations are derived to describe this system; these include the imposed blowing/suction as well as inertia, surface tension, gravity and viscosity. The case of spatially periodic blowing and suction is considered in detail and the bifurcation structure of forced steady states is explored numerically to predict that steady states cease to exist for sufficiently large suction speeds since the film locally thins to zero thickness giving way to dry patches on the substrate. The linear stability of the resulting nonuniform steady states is investigated for perturbations of arbitrary wavelengths, and any instabilities are followed into the fully nonlinear regime using time-dependent computations. The case of small amplitude blowing/suction is studied analytically both for steady states and their stability. Finally, the transition between travelling waves and non-uniform steady states is explored as the suction amplitude increases.

  20. Infection levels of plerocercoids of the tapeworm Triaenophorus crassus and feeding strategy in two fish species from the ultra-oligotrophic Lake Achensee, Austria.

    PubMed

    Schähle, Z; Medgyesy, N; Psenner, R

    2016-01-01

    Thus far, high burdens of Triaenophorus crassus plerocercoids have been reported only in old age groups of coregonid and salmonid fishes. Here we show heavy infection with T. crassus in young whitefish Coregonus lavaretus in the ultra-oligotrophic and regulated Achensee in Tyrol, Austria. Prevalence of T. crassus on C. lavaretus was 100% in all age groups and abundance significantly increased with fish age. The mean annual accumulation of T. crassus was 5.2 parasites in 0- to 7-year-old C. lavaretus, and 2-year-old specimens already harboured a mean of 19.4 plerocercoids. In Arctic charr Salvelinus umbla, however, the prevalence of T. crassus was less than 16% and the majority of infected fish contained only one or two plerocercoids. Triaenophorus nodulosus was present neither in C. lavaretus nor in S. umbla. We assume that the heavy T. crassus infection in C. lavaretus is largely related to their zooplankton-dominated diet and to the characteristics of Achensee, while habitat choice and feeding strategy of the S. umbla population are seen to be the main reasons for their low burdens of T. crassus. PMID:25345803

  1. Remotely operated submersible underwater suction apparatus

    DOEpatents

    Kristan, Louis L.

    1990-01-01

    A completely submersible, remotely operated underwater suction device for collection of irradiated materials in a nuclear pool is disclosed. The device includes a pump means for pumping water through the device, a filter means for capturing irradiated debris, remotely operated releasable connector means, a collection means and a means for remotely maneuvering the collection means. The components of the suction device may be changed and replaced underwater to take advantage of the excellent radiation shielding ability of water to thereby minimize exposure of personnel to radiation.

  2. Influence of salinity regime on the food-web structure and feeding ecology of fish species from Mediterranean coastal lagoons

    NASA Astrophysics Data System (ADS)

    Prado, Patricia; Vergara, Carolina; Caiola, Nuno; Ibáñez, Carles

    2014-02-01

    Dual δ15N and δ13C analyses and estimates of biomass were used to characterize the food webs of valuable fish species in three coastal lagoons of the Ebro Delta subjected to contrasting salinity regimes (polyhaline in the Tancada lagoon, mesohaline in the Encanyissada and oligohaline in the Clot lagoon). The δ13C signatures of the entire food-web including primary producers, sediment organic matter and consumers showed the most enriched values in the Tancada lagoon (from approx. -4.8‰ in sediments to -19.7‰ in fish) and the most depleted ones in the Clot lagoon (from approx. -11.4‰ in sediments to -25.4‰ in fish), consistent with dominant contributions from marine and continental sources, respectively. For δ15N, particularly high values were detected in the submersed vegetation (11.3 ± 0.3‰) together with more enriched sediment values at lower salinities (by approx. 2.5‰), suggesting that historical loadings of agricultural fertilizers are still retained by the systems and transmitted across trophic levels. Negative relationships between δ15N and salinity were also observed for the amphipod Gammarus aequicauda and the isopod Sphaeroma hookeri, suggesting some consumption of accumulated and resuspended detrital material. In contrast, δ15N signatures of fish showed lower values and inconsistent patterns, possibly because most species have a seasonal use of the lagoons. The biomass of fish species did not show a clear effect of the salinity regime (except for the mosquitofish Gambusia holbrookii), but results for mixing models suggest a diet shift from higher contribution of zooplankton size fractions in the Encanyissada (from 57 to 73%) to macrofauna at the other lagoons (from 40 to 67%). We suggest that alterations in salinity might modify the trophic dynamics of the systems from benthic to planktonic pathways, without large-scale differences in δ15N of fish suggestive of similar trophic levels.

  3. The feeding habits of Austrolethops wardi, a gobiid fish inhabiting burrows of the thalassinidean shrimp Neaxius acanthus

    NASA Astrophysics Data System (ADS)

    Hung Liu, Ha Trieu; Kneer, Dominik; Asmus, Harald; Ahnelt, Harald

    2008-09-01

    The feeding habit of Austrolethops wardi (Gobiidae) in the seagrass beds of Barrang Lompo and Bone Batang Island in the Spermonde Archipelago, South West Sulawesi, Indonesia, was investigated through gut content analysis. The feeding preferences of this species are very similar on both islands: A. wardi, a burrow associate of Neaxius acanthus, was found to feed almost exclusively on seagrass (which was found in 100% of the investigated stomachs and made up >94% of food items). However, seagrass epiphytes (<5% of food items) and animal food (<1% of food items) occurred in the guts as well, the latter predominantly in terms of copepods and to a lesser degree in other small invertebrates. These results indicate that animal food is of little importance for A. wardi. Some specimens even contained no parts of animal food.

  4. A novel visual sputum suctioning system is useful for endotracheal suctioning in a dog model

    PubMed Central

    Liu, Xun; Deng, Huisheng; Huang, Ziyang; Yan, Bingbing; Lv, Jingjing; Wu, Jinxing

    2014-01-01

    Objective: This study is to test the effectiveness of fiber-optic-guided endotracheal suction catheter (visual sputum suctioning system or VSSS) in dog models. Methods: Dog sputum models were established by administering dimethoate emulsifiable. Twenty-seven intubated dogs were equally randomized into three groups of conventional suctioning (CS) group, VSSS with no supplemental oxygen (VSSS) group and VSSS with 100% oxygen (VSSS/O2) group. The suctioning efficiency, vital signs and tracheal wall injury were assessed. Results: The VSSS/O2 (8.6 ± 0.7g) and VSSS groups (8.5 ± 0.9 g) collected significantly more sputum than the CS group (5.9 ± 0.8 g) (P < 0.05 for VSSS/O2 group versus CS group; P < 0.05 for VSSS group versus CS group). Immediately after suctioning, the arterial partial pressure of oxygen (PaO2) of VSSS/O2 group was significantly higher than that of the VSSS group or the CS group (both P < 0.05), and 5 min after suction the PaO2, the mean arterial pressure (MAP) and heart rate (HR) in all groups returned to the baseline (p = 0.54, P = 0.67, P = 0.11, respectively). Moreover, in the VSSS/O2 and VSSS groups all the three variables were higher than the CS group at 5 min after suctioning (P < 0.01, P = 0.03; P = 0.02, P < 0.01; P = 0.02, P = 0.01 respectively). Conclusions: Visual sputum suctioning system collected more sputum and caused less tracheal mucosa damage than conventional suctioning. PMID:25663978

  5. Feeding soy or fish meal to Alaskan reindeer (Rangifer tarandus tarandus) - effects on animal performance and meat quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fourteen reindeer were used to compare the effects of two different reindeer diets containing soybean meal (SBM) or fishmeal (WFM) as protein source) on animal growth performance, feed efficiency and ultimate meat quality. No significant difference was observed in overall weight gain between the WFM...

  6. Integrated assessment of runoff from concentrated animal feeding operations: Analytical approaches, in vitro bioassays, and in vivo fish exposures

    EPA Science Inventory

    While the trend toward using concentrated animal feeding operations (CAFOs) has resulted in increased efficiency in food production, this has prompted concern regarding the impact these operations have on the environment. For example, animal waste from CAFOs can contain natural a...

  7. Assessing impacts of land-applied manure from concentrated animal feeding operations on fish populations and communities

    EPA Science Inventory

    Concentrated animal feeding operation (CAFO) waste is a cost effective fertilizer. In the Midwest, networks of subsurface tile-drains expedite transport of animal hormones and nutrients from land-applied CAFO waste to adjacent waterways. The objective of this study was to evaluat...

  8. 21 CFR 884.1175 - Endometrial suction curette and accessories.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... suction curette is a device used to remove material from the uterus and from the mucosal lining of the uterus by scraping and vacuum suction. This device is used to obtain tissue for biopsy or for...

  9. 21 CFR 884.1175 - Endometrial suction curette and accessories.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... suction curette is a device used to remove material from the uterus and from the mucosal lining of the uterus by scraping and vacuum suction. This device is used to obtain tissue for biopsy or for...

  10. 21 CFR 884.1175 - Endometrial suction curette and accessories.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... suction curette is a device used to remove material from the uterus and from the mucosal lining of the uterus by scraping and vacuum suction. This device is used to obtain tissue for biopsy or for...

  11. 21 CFR 884.1175 - Endometrial suction curette and accessories.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... suction curette is a device used to remove material from the uterus and from the mucosal lining of the uterus by scraping and vacuum suction. This device is used to obtain tissue for biopsy or for...

  12. 21 CFR 884.1175 - Endometrial suction curette and accessories.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... suction curette is a device used to remove material from the uterus and from the mucosal lining of the uterus by scraping and vacuum suction. This device is used to obtain tissue for biopsy or for...

  13. Durophagy in sharks: feeding mechanics of the hammerhead Sphyrna tiburo.

    PubMed

    Wilga, C D; Motta, P J

    2000-09-01

    This study investigates the motor pattern and head movements during feeding of a durophagus shark, the bonnethead Sphyrna tiburo, using electromyography and simultaneous high-speed video. Sphyrna tiburo feeds almost exclusively on hard-shelled crabs, with shrimp and fish taken occasionally. It captures crabs by ram feeding, then processes or reduces the prey by crushing it between molariform teeth, finally transporting the prey by suction for swallowing. The prey-crushing mechanism is distinct from that of ram or bite capture and suction transport. This crushing mechanism is accomplished by altering the duration of jaw adductor muscle activity and modifying jaw kinematics by the addition of a second jaw-closing phase. In crushing events, motor activity of the jaw adductor muscles continues (biting of the prey occurs as the jaws close and continues after the jaws have closed) throughout a second jaw-closing phase, unlike capture and transport events during which motor activity (biting) ceases at jaw closure. Sphyrna tiburo is able to take advantage of a resource (hard prey) that is not readily available to most sharks by utilizing a suite of durophagous characteristics: molariform teeth, a modified jaw protrusor muscle, altered jaw adductor activity and modified jaw kinematics. Sphyrna tiburo is a specialist feeder on crab prey as demonstrated by the lack of differences in kinematic or motor patterns when offered prey of differing hardness and its apparent lack of ability to modulate its behavior when feeding on other prey. Functional patterns are altered and coupled with modifications in dental and jaw morphology to produce diverse crushing behaviors in elasmobranchs. PMID:10952878

  14. 21 CFR 870.5050 - Patient care suction apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Patient care suction apparatus. 870.5050 Section 870.5050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... suction apparatus. (a) Identification. A patient care suction apparatus is a device used with...

  15. 21 CFR 870.5050 - Patient care suction apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Patient care suction apparatus. 870.5050 Section 870.5050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... suction apparatus. (a) Identification. A patient care suction apparatus is a device used with...

  16. Experimental study of flow due to an isolated suction hole and a partially plugged suction slot

    NASA Technical Reports Server (NTRS)

    Goglia, G. L.; Wilkinson, S. P.

    1980-01-01

    Details for construction of a model of a partially plugged, laminar flow control, suction slot and an isolated hole are presented. The experimental wind tunnel facility and instrumentation is described. Preliminary boundary layer velocity profiles (without suction model) are presented and shown to be in good agreement with the Blasius laminar profile. Recommendations for the completion of the study are made. An experimental program for study of transition on a rotating disk is described along with preliminary disturbance amplification rate data.

  17. Whale Sharks, Rhincodon typus, Aggregate around Offshore Platforms in Qatari Waters of the Arabian Gulf to Feed on Fish Spawn

    PubMed Central

    Robinson, David P.; Jaidah, Mohammed Y.; Jabado, Rima W.; Lee-Brooks, Katie; Nour El-Din, Nehad M.; Malki, Ameena A. Al.; Elmeer, Khaled; McCormick, Paul A.; Henderson, Aaron C.; Pierce, Simon J.; Ormond, Rupert F. G.

    2013-01-01

    Whale sharks, Rhincodon typus, are known to aggregate to feed in a small number of locations in tropical and subtropical waters. Here we document a newly discovered major aggregation site for whale sharks within the Al Shaheen oil field, 90 km off the coast of Qatar in the Arabian Gulf. Whale sharks were observed between April and September, with peak numbers observed between May and August. Density estimates of up to 100 sharks within an area of 1 km2 were recorded. Sharks ranged between four and eight metres’ estimated total length (mean 6.92±1.53 m). Most animals observed were actively feeding on surface zooplankton, consisting primarily of mackerel tuna, Euthynnus affinis, eggs. PMID:23516456

  18. Whale sharks, Rhincodon typus, aggregate around offshore platforms in Qatari waters of the Arabian Gulf to feed on fish spawn.

    PubMed

    Robinson, David P; Jaidah, Mohammed Y; Jabado, Rima W; Lee-Brooks, Katie; Nour El-Din, Nehad M; Al Malki, Ameena A; Elmeer, Khaled; McCormick, Paul A; Henderson, Aaron C; Pierce, Simon J; Ormond, Rupert F G

    2013-01-01

    Whale sharks, Rhincodon typus, are known to aggregate to feed in a small number of locations in tropical and subtropical waters. Here we document a newly discovered major aggregation site for whale sharks within the Al Shaheen oil field, 90 km off the coast of Qatar in the Arabian Gulf. Whale sharks were observed between April and September, with peak numbers observed between May and August. Density estimates of up to 100 sharks within an area of 1 km(2) were recorded. Sharks ranged between four and eight metres' estimated total length (mean 6.92 ± 1.53 m). Most animals observed were actively feeding on surface zooplankton, consisting primarily of mackerel tuna, Euthynnus affinis, eggs. PMID:23516456

  19. Bite force and feeding kinematics in the eastern North Pacific Kyphosidae.

    PubMed

    Moran, Clinton Joseph; Ferry, Lara

    2014-04-01

    Some fishes that feed on attached food items possess an intramandibular joint (IMJ), which is thought to increase maximum gape and facilitate contact between the tooth-bearing surface and the substrate. However, the mechanical consequences of using an IMJ to remove attached food items from the substrate are still poorly understood. We examined the most prominent eastern North Pacific kyphosid, the scraper: Girella nigricans and two other kyphosids, Medialuna californiensis and Hermosilla azurea, which occupy similar habitats. Of the three species, G. nigricans had the highest theoretical bite force per unit length. We examined the feeding mechanics of G. nigricans in two different feeding scenarios: a scraping behavior elicited on a block of brine shrimp gelatin and a picking behavior elicited on Ulva sp. We measured cranial elevation, lower jaw rotation, premaxillary protrusion, premaxillary rotation, gape maximum, and intramandibular rotation. Ulva treatments produced significantly greater cranial rotation, when compared to gelatin treatments. Gelatin treatments were associated with greater lower jaw rotation and larger gape. Premaxillary rotation and premaxillary protrusion did not differ between treatments. Intramandibular rotation occurred only when G. nigricans physically contacted the gelatin, suggesting the IMJ is a passive joint with no associated musculature. We also noted that G. nigricans do not appear to use suction to draw food into the mouth. The lack of suction and the presence of the IMJ suggest that the jaws of G. nigricans are specialized for maximizing jaw force when scraping. PMID:24497484

  20. Molecular epidemiology of Salmonella spp. isolates from gulls, fish-meal factories, feed factories, animals and humans in Norway based on pulsed-field gel electrophoresis.

    PubMed Central

    Nesse, L. L.; Refsum, T.; Heir, E.; Nordby, K.; Vardund, T.; Holstad, G.

    2005-01-01

    The molecular epidemiology of 98 isolates of Salmonella serovar Agona (n = 27), S. Montevideo (n = 42) and S. Senftenberg (n = 29) from wild-living gulls, fish-meal factories, feed factories, humans and domestic animals was investigated using pulsed-field gel electrophoresis (PFGE) and computerized numerical analysis. Two of the S. Agona profiles were identified both in gulls and in two of the factories. In addition, one of these profiles was detected in two infected poultry farms. Two of the S. Montevideo profiles were also identified both in gulls and in two of the factories, and one of these profiles was observed in a human isolate. Four factories shared an identical S. Senftenberg profile. The S. Senftenberg profile found in gulls was not identified in any other source investigated. The presence of isolates with identical PFGE profiles indicates potential epidemiological links between different factories, as well as between gulls and factories. PMID:15724711

  1. Salmon testes meal as a functional feed additive in fish meal and plant-protein based diets for rainbow trout(Oncorhynchus mykiss walbaum)and nile tilapia(Oreochromis niloticus L.) fry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report that salmon testes meal (TM) produced from Alaskan seafood processing byproducts is a potential protein source for aquafeed formulations. A series of feeding trials was conducted using three different fish species; including Nile tilapia, rainbow trout, and white sturgeon at their early gr...

  2. Apparent digestibility of Asian carp and common carp-derived fish meals in feeds for hybrid striped bass Morone saxatilis female x M. chrysops male and rainbow trout Oncorhynchus mykiss

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Apparent digestibility coefficients (ADCs) of nutrients (crude protein, amino acids, crude lipid, fatty acids, and minerals) were determined for fish meals derived from menhaden, Asian carp (combination of silver and bighead carps), and common carp in feeds for hybrid striped bass and rainbow trout....

  3. Environmental concentrations of the selective serotonin reuptake inhibitor fluoxetine impact specific behaviors involved in reproduction, feeding and predator avoidance in the fish Pimephales promelas (fathead minnow)

    PubMed Central

    Weinberger, Joel; Klaper, Rebecca

    2014-01-01

    Pharmaceuticals and personal care products (PPCP) have been found in surface waters worldwide, but little is understood of their effects on the wildlife that inhabit these waters. Fluoxetine (Prozac; Eli Lilly), a highly prescribed selective serotonin reuptake inhibitor (SSRI), is a commonly found PPCP in surface water. The purpose of this project was to determine if environmentally relevant concentrations of fluoxetine impact behavior that is important for population survival in native fish species, including reproduction, feeding and predator avoidance. Chronic 4-week exposures were conducted with doses ranging from 100 ng/L to 100 μg/L to cover a range of environmentally relevant concentrations up to higher concentrations comparable to other published studies with the same drug that have documented various physiological impacts. Pimephales promelas (fathead minnow), a species native to North America, was used as it conducts a range of specific mating behaviors and therefore serves as an excellent model of specific impacts on brain function. Fluoxetine concentrations as low as 1 μg/L, a concentration that has been found in many freshwater environments, were found to significantly impact mating behavior, specifically nest building and defending in male fish. Males were also found to display aggression, isolation, and repetitive behaviors at higher concentrations. Female mating behavior was largely unaffected. In addition, predator avoidance behaviors in males and females were also impacted at 1 μg/L. Feeding was impacted at 10 μg/L and in the highest exposure (100 μg/L), egg production was limited by deaths of females due to significant male aggressive behaviors in first two weeks of exposure. Specific behavioral changes occurred at each concentration (most noticeably 1 μg/L and 100 μg/L) indicating a dose dependent effect that triggered different responses at lower exposures versus higher exposures or differential impacts of dose depending on brain region

  4. Optimal concentrations in nectar feeding

    PubMed Central

    Kim, Wonjung; Gilet, Tristan; Bush, John W. M.

    2011-01-01

    Nectar drinkers must feed quickly and efficiently due to the threat of predation. While the sweetest nectar offers the greatest energetic rewards, the sharp increase of viscosity with sugar concentration makes it the most difficult to transport. We here demonstrate that the sugar concentration that optimizes energy transport depends exclusively on the drinking technique employed. We identify three nectar drinking techniques: active suction, capillary suction, and viscous dipping. For each, we deduce the dependence of the volume intake rate on the nectar viscosity and thus infer an optimal sugar concentration consistent with laboratory measurements. Our results provide the first rationale for why suction feeders typically pollinate flowers with lower sugar concentration nectar than their counterparts that use viscous dipping. PMID:21949358

  5. Does feeding behavior facilitate trophic niche partitioning in two sympatric sucker species from the American Southwest?

    PubMed

    O'Neill, Matthew W; Gibb, Alice C

    2014-01-01

    We examined two sympatric desert fishes, Sonora suckers (Catostomus insignis) and desert suckers (Pantosteus clarkii), and asked, does feeding behavior facilitate trophic niche partitioning? To answer this question, we conducted laboratory-based feeding trials to determine whether morphology alone facilitates the diet separation between the relatively unspecialized, omnivorous Sonora sucker and the more morphologically specialized, algivorous desert sucker or whether behavioral differences accompany morphological specialization. We predicted that (1) algivorous desert suckers would maximize contact between jaws and substrate and produce a large mouth-gape to facilitate scraping attached food-material; (2) omnivorous Sonora suckers would be more effective suction feeders when consuming unattached food items from the benthos; and (3) because they are anatomically specialized for scraping, desert suckers could not alter their feeding behavior when presented with different prey types, whereas relatively unspecialized Sonora suckers could vary behavior with prey type. We found that both species maximized jaw contact when feeding on benthic-attached food, although desert suckers produced a greater gape area. We also found that Sonora suckers were more effective suction feeders when feeding on benthic-unattached prey. Counter to our initial predictions, both species altered key aspects of feeding behavior in response to different prey types/locations. It appears that both sucker species can function as generalist feeders to exploit a variety of prey types within their natural habitat; indeed, this behavioral versatility may allow desert and Sonora suckers to respond to the cyclic environmental changes that are characteristic of the aquatic habitats of the American Southwest. PMID:24457922

  6. Bernoulli Suction Effect on Soap Bubble Blowing?

    NASA Astrophysics Data System (ADS)

    Davidson, John; Ryu, Sangjin

    2015-11-01

    As a model system for thin-film bubble with two gas-liquid interfaces, we experimentally investigated the pinch-off of soap bubble blowing. Using the lab-built bubble blower and high-speed videography, we have found that the scaling law exponent of soap bubble pinch-off is 2/3, which is similar to that of soap film bridge. Because air flowed through the decreasing neck of soap film tube, we studied possible Bernoulli suction effect on soap bubble pinch-off by evaluating the Reynolds number of airflow. Image processing was utilized to calculate approximate volume of growing soap film tube and the volume flow rate of the airflow, and the Reynolds number was estimated to be 800-3200. This result suggests that soap bubbling may involve the Bernoulli suction effect.

  7. Ultra-fast underwater suction traps

    PubMed Central

    Vincent, Olivier; Weißkopf, Carmen; Poppinga, Simon; Masselter, Tom; Speck, Thomas; Joyeux, Marc; Quilliet, Catherine; Marmottant, Philippe

    2011-01-01

    Carnivorous aquatic Utricularia species catch small prey animals using millimetre-sized underwater suction traps, which have fascinated scientists since Darwin's early work on carnivorous plants. Suction takes place after mechanical triggering and is owing to a release of stored elastic energy in the trap body accompanied by a very fast opening and closing of a trapdoor, which otherwise closes the trap entrance watertight. The exceptional trapping speed—far above human visual perception—impeded profound investigations until now. Using high-speed video imaging and special microscopy techniques, we obtained fully time-resolved recordings of the door movement. We found that this unique trapping mechanism conducts suction in less than a millisecond and therefore ranks among the fastest plant movements known. Fluid acceleration reaches very high values, leaving little chance for prey animals to escape. We discovered that the door deformation is morphologically predetermined, and actually performs a buckling/unbuckling process, including a complete trapdoor curvature inversion. This process, which we predict using dynamical simulations and simple theoretical models, is highly reproducible: the traps are autonomously repetitive as they fire spontaneously after 5–20 h and reset actively to their ready-to-catch condition. PMID:21325323

  8. Practical success of biomanipulation using filter-feeding Fish to control cyanobacteria blooms: a synthesis of decades of research and application in a subtropical hypereutrophic lake.

    PubMed

    Xie, P; Liu, J

    2001-08-01

    Lake Donghu is a 32-km2 shallow, subtropical lake near the Yangtze River (P.R. China) that has experienced dramatic changes in the past five decades. These changes include: (1) a trophic state change from mesotrophy to hypertrophy; (2) dense blooms of cyanobacteria during every summer from the 1970s to 1984; (3) a cessation of blooms starting in 1985, with no recurrence; and (4) an increase, coincident with bloom declines, in the production of silver and bighead carp (filter-feeders) by more than tenfold. There are several possible explanations for the disappearance of blooms, including changes in nutrient concentrations, increased zooplankton grazing, and increased grazing on algae by fish. The long-term data suggest that changes in nutrients or in zooplankton were not important, but that the remarkably increased fish densities might have played the key role. To test this hypothesis, in situ enclosure experiments were conducted in three years. The main conclusions are as follows: (1) an increased stocking of the lake with carp played a decisive role in the elimination of cyanobacteria blooms; (2) both silver and bighead carp can eliminate cyanobacteria blooms directly by grazing; (3) zooplankton cannot suppress the blooms; and (4) the lake still is vulnerable to the outbreak of blooms, should fish grazing decline. The critical biomass of carp is approximately 50 g m3. The results suggest the applicability of a new food-web manipulation (increased stocking with filter-feeding fish) for controlling cyanobacteria blooms in hypereutrophic lakes. The approach differs from traditional biomanipulation in Europe and North America, where piscivores are added to control planktivores, and this in turn increases zooplankton and decreases algae. The new biomanipulation method is being used or being tested to counteract cyanobacteria blooms in many Chinese lakes such as Lake Dianchi in Yunnan Province, Lake Chaohu in Anhui Province, and Lake Taihu in Jiangsu Province. The

  9. Sustainable production of toxin free marine microalgae biomass as fish feed in large scale open system in the Qatari desert.

    PubMed

    Das, Probir; Thaher, Mahmoud Ibrahim; Hakim, Mohammed Abdul Quadir Mohd Abdul; Al-Jabri, Hareb Mohammed S J

    2015-09-01

    Mass cultivation of microalgae biomass for feed should be cost effective and toxin free. Evaporation loss in Qatar can be as high as 2 cm/d. Hence, production of marine microalgae biomass in Qatar would also require mitigating water loss as there was only very limited groundwater reserve. To address these issues, a combination of four growth conditions were applied to a 25,000 L raceway pond: locally isolated microalgae strain was selected which could grow in elevated salinity; strain that did not require silica and vitamins; volume of the culture would increase over time keeping denser inoculum in the beginning, and evaporation water loss would be balanced by adding seawater only. A local saline tolerant Nannochloropsis sp. was selected which did not require silica and vitamins. When the above conditions were combined in the pond, average areal biomass productivities reached 20.37 g/m(2)/d, and the culture was not contaminated by any toxic microalgae. PMID:26022971

  10. Feeding kinematics and performance of Hawaiian stream gobies, Awaous guamensis and Lentipes concolor: linkage of functional morphology and ecology.

    PubMed

    Maie, Takashi; Wilson, Megan P; Schoenfuss, Heiko L; Blob, Richard W

    2009-03-01

    Distributions of Hawaiian stream fishes are typically interrupted by waterfalls that divide streams into multiple segments. Larvae hatch upstream, are flushed into the ocean, and must climb these waterfalls to reach adult habitats when returning back to freshwater as part of an amphidromous life cycle. Stream surveys and studies of climbing performance show that Lentipes concolor Gill can reach fast-flowing upper stream segments but that Awaous guamensis Valenciennes reaches only slower, lower stream segments. Gut content analyses for these two species indicate considerable overlap in diet, suggesting that feeding kinematics and performance of these two species might be comparable. Alternatively, feeding kinematics and performance of these species might be expected to differ in relation to the different flow regimes in their habitat (feeding in faster stream currents for L. concolor versus in slower currents for A. guamensis). To test these alternative hypotheses, we compared food capturing kinematics and performance during suction feeding behaviors of A. guamensis and L. concolor using morphological data and high-speed video. Lentipes concolor showed both a significantly larger gape angle and faster jaw opening than A. guamensis. Geometric models calculated that despite the inverse relationship of gape size and suction pressure generation, the fast jaw motions of L. concolor allow it to achieve higher pressure differentials than A. guamensis. Such elevated suction pressure would enhance the ability of L. concolor to successfully capture food in the fast stream reaches it typically inhabits. Differences in jaw morphology may contribute to these differences in performance, as the lever ratio for jaw opening is about 10% lower in L. concolor compared with A. guamensis, suiting the jaws of L. concolor better for fast opening. PMID:19107821

  11. Effects of oxidised dietary fish oil and high-dose vitamin E supplementation on growth performance, feed utilisation and antioxidant defence enzyme activities of juvenile large yellow croaker (Larmichthys crocea).

    PubMed

    Wang, Jun; Xu, Houguo; Zuo, Rantao; Mai, Kangsen; Xu, Wei; Ai, Qinghui

    2016-05-01

    This study was conducted to elucidate the effects of oxidised dietary lipids and high-dose vitamin E (VE) on growth performance and immune responses of large yellow croaker. Juvenile fish (initial average body weight of 7·82 (sem 0·68) g) were fed diets containing either fresh fish oil (fresh diet, peroxide value (POV)=1·72 mEq/kg) or fish oil oxidised to varying degrees (oxidised diets, POV=28·29-104·21 mEq/kg), with or without supplementary 600 mg VE/kg diet, for 10 weeks in floating cages. Growth was significantly lower and feed intake (g/100 g body weight per d) was higher in fish fed the oxidised diet. Supplementation with VE increased the growth of fish fed the oxidised diets, but significantly decreased the growth of fish fed the fresh diet. Hepatosomatic index increased with increasing dietary POV and decreased with VE supplementation. Hepatic catalase activity, superoxide dismutase (SOD) activity and malondialdehyde content were significantly higher in fish fed the oxidised diets, and these values decreased significantly following VE supplementation. However, hepatic SOD activity was enhanced by VE supplementation in fish fed the fresh diet. Air-exposure mortality was significantly increased by dietary POV, and this effect was inhibited by VE supplementation. These results suggest that dietary oxidised fish oil could stimulate the activities of antioxidant defence enzymes in stressed large yellow croaker. High-dose VE supplementation can alleviate oxidative stress of large yellow croaker fed oxidised fish oil, but can exert deleterious effects on fish in the absence of oxidative stress. PMID:26948923

  12. Heterospecific aggression and dominance in a guild of coral-feeding fishes: the roles of dietary ecology and phylogeny.

    PubMed

    Blowes, Shane A; Pratchett, Morgan S; Connolly, Sean R

    2013-08-01

    Interspecific competition mediates biodiversity maintenance and is an important selective pressure for evolution. Competition is often conceptualized as being exploitative (indirect) or involving direct interference. However, most empirical studies are phenomenological, focusing on quantifying effects of density manipulations, and most competition theory has characterized exploitation competition systems. The effects on resource use of traits associated with direct, interference competition has received far less attention. Here we examine the relationships of dietary ecology and phylogeny to heterospecific aggression in a guild of corallivorous reef fishes. We find that, among chaetodontids (butterflyfishes), heterospecific aggression depends on a synergistic interaction of dietary overlap and specialization: aggression increases with dietary overlap for interactions between specialists but not for interactions involving generalists. Moreover, behavioral dominance is a monotonically increasing function of dietary specialization. The strong, positive relationship of dominance to specialization suggests that heterospecific aggression may contribute to the maintenance of biodiversity where it promotes resource partitioning. Additionally, we find strong phylogenetic signals in dietary overlap and specialization but not behavioral dominance. Our results support the use of phylogeny as a proxy for ecological similarity among butterflyfishes, but we find that direct measures of dietary overlap and specialization predict heterospecific agression much better than phylogeny. PMID:23852351

  13. [What is the benefit of subglottic suction?].

    PubMed

    Stuttmann, R; Weidemann, D; Doehn, M

    1987-02-01

    Bronchopulmonary infections are the main cause of morbidity and mortality in intensive care wards. Since the usual anatomical and physiological barrier is missing in the intubated patient, oropharyngeal secretion will reach the subglottic space between glottis and upper rim of the low-pressure cuff. Starting from there, continuous microaspiration between cuff and tracheal mucosa leads to bacterial contamination of the upper respiratory tract. In patients with a disturbed immune system from that point on colonization and infection may follow. Therefore one is called upon to search for measures to prevent infection in ventilated patients. Selective decontamination of oropharynx and gastrointestinal tract has been described as an effective method. Others are recommending the application of aminoglycosides in the tracheobroncheal system. Removing retained secreted material is a general surgical principle. Therefore we tested the practicability and effectiveness of a continuous subglottic drainage. At this point we are mainly interested in its clinical aspects and in the method. We investigated the subglottic drainage in 10 intensive care patients who were on long-term mechanical ventilation and had undergone tracheostomy. All patients had an Ultratracheoflex cannula Nr. 9-11 (Rüsch Company, West Germany). It was modified by a suction catheter Ch. 12 (Uno Plast Company, West Germany): We cut two additional small holes in the curved catheter tip and attached the catheter with this part above the cuff at the dorsal convexity to the tracheoflex cannula (see illustration 1). An infusion pump was used for suctioning secretion from the subglottic space by an ordinary infusion set and at a suction flow of 100-125 ml/h.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3578752

  14. Screening of pesticides and polycyclic aromatic hydrocarbons in feeds and fish tissues by gas chromatography coupled to high-resolution mass spectrometry using atmospheric pressure chemical ionization.

    PubMed

    Nácher-Mestre, Jaime; Serrano, Roque; Portolés, Tania; Berntssen, Marc H G; Pérez-Sánchez, Jaume; Hernández, Félix

    2014-03-12

    This paper reports a wide-scope screening for detection and identification of pesticides and polycyclic aromatic hydrocarbons (PAHs) in feeds and fish tissues. QuEChERS sample treatment was applied, using freezing as an additional cleanup. Analysis was carried out by gas chromatography coupled to hybrid quadrupole time-of-flight mass spectrometry with atmospheric pressure chemical ionization (GC-(APCI) QTOF MS). The qualitative validation was performed for over 133 representative pesticides and 24 PAHs at 0.01 and 0.05 mg/kg. Subsequent application of the screening method to aquaculture samples made it possible to detect several compounds from the target list, such as chlorpyrifos-methyl, pirimiphos-methyl, and ethoxyquin, among others. Light PAHs (≤4 rings) were found in both animal and vegetable samples. The reliable identification of the compounds was supported by accurate mass measurements and the presence of at least two representative m/z ions in the spectrum together with the retention time of the peak, in agreement with the reference standard. Additionally, the search was widened to include other pesticides for which standards were not available, thanks to the expected presence of the protonated molecule and/or molecular ion in the APCI spectra. This could allow the detection and tentative identification of other pesticides different from those included in the validated target list. PMID:24559176

  15. Preliminary insights into the incorporation of rosemary extract (Rosmarinus officinalis L.) in fish feed: influence on performance and physiology of gilthead seabream (Sparus aurata).

    PubMed

    Hernández, A; García García, B; Caballero, M J; Hernández, M D

    2015-08-01

    Gilthead seabream (Sparus aurata) were fed a basal (control) diet and four experimental diets (R600, R1200, R1800 and R2400), containing 600, 1200, 1800 and 2400 mg kg(-1), respectively, of rosemary extract (Rosmarinus officinalis L.). At 4 and 12 weeks from the beginning of the ongrowing period, the fish were sacrificed, blood was drawn to obtain plasma and the liver and intestines were dissected. Growth and feed intake were unaffected by rosemary extract addition. A histological examination of the intestine revealed no differences among the dosages, while the liver showed a sharp decrease in hepatic steatosis in diets supplemented with rosemary extract. Furthermore, plasma alanine aminotransferase was lower with these diets at the end of the ongrowing period. Rosemary extract reduced the plasma levels of glucose and triglycerides on week 4 and glucose and HDL/LDL cholesterol ratio on week 12, suggesting better transport and energy metabolism of the lipids. Overall, the most evident effect of rosemary extract was observed with the 600 mg kg(-1) dose. PMID:25968936

  16. Effect of replacing fish meal with extruded soybean meal on growth, feed utilization and apparent nutrient digestibility of juvenile white shrimp ( Litopenaeus vannamei)

    NASA Astrophysics Data System (ADS)

    Yang, Qihui; Tan, Beiping; Dong, Xiaohui; Chi, Shuyan; Liu, Hongyu

    2015-10-01

    Extruded soybean meal (ESBM) was evaluated as a protein source for partial replacement of fish meal (FM) in diets of juvenile Litopenaeus vannamei. In the control diet (Diet 1), FM protein was replaced with increasing dietary levels of ESBM (4.28%, 8.40%, 12.62%, 16.82%, and 25.26%) at 10%, 20%, 30%, 40%, and 60% levels (Diets 2 to 6, respectively). An eight-week feeding trial was conducted on 720 juvenile shrimp (0.67 g ± 0.01 g mean initial weight), and nutrient digestibility of the six diets was determined. ESBM could replace 20% of FM without causing a significant reduction in growth of shrimp, but other dietary treatments strongly affected whole body composition. Crude protein content of the whole body fed Diet 6 was significantly lower than that fed Diet 2 ( P < 0.05), while crude lipid content of the whole body fed Diet 5 or 6 was significantly higher than that fed Diet 2 ( P < 0.05). Protein digestibilities of Diets 5 and 6 were significantly lower than that of Diet 1 ( P < 0.05). Digestibility of lipids ranged from 96.97% in Diet 6 to 98.34% in Diet 3, whereas dry matter digestibility decreased with increasing replacement level. This study indicates that 20% FM replacement with ESBM in the basic diet containing 40% protein and 30% FM is optimal for juvenile L. vannamei.

  17. Aquatic prey capture in ray-finned fishes: a century of progress and new directions.

    PubMed

    Ferry-Graham, L A; Lauder, G V

    2001-05-01

    The head of ray-finned fishes is structurally complex and is composed of numerous bony, muscular, and ligamentous elements capable of intricate movement. Nearly two centuries of research have been devoted to understanding the function of this cranial musculoskeletal system during prey capture in the dense and viscous aquatic medium. Most fishes generate some amount of inertial suction to capture prey in water. In this overview we trace the history of functional morphological analyses of suction feeding in ray-finned fishes, with a particular focus on the mechanisms by which suction is generated, and present new data using a novel flow imaging technique that enables quantification of the water flow field into the mouth. We begin with a brief overview of studies of cranial anatomy and then summarize progress on understanding function as new information was brought to light by the application of various forms of technology, including high-speed cinematography and video, pressure, impedance, and bone strain measurement. We also provide data from a new technique, digital particle image velocimetry (DPIV) that allows us to quantify patterns of flow into the mouth. We believe that there are three general areas in which future progress needs to occur. First, quantitative three-dimensional studies of buccal and opercular cavity dimensions during prey capture are needed; sonomicrometry and endoscopy are techniques likely to yield these data. Second, a thorough quantitative analysis of the flow field into the mouth during prey capture is necessary to understand the effect of head movement on water in the vicinity of the prey; three-dimensional DPIV analyses will help to provide these data. Third, a more precise understanding of the fitness effects of structural and functional variables in the head coupled with rigorous statistical analyses will allow us to better understand the evolutionary consequences of intra- and interspecific variation in cranial morphology and function

  18. Effects of feed access after hatch and inclusion of fish oil and medium chain fatty acids in a pre-starter diet on broiler chicken growth performance and humoral immunity.

    PubMed

    Lamot, D M; van der Klein, S A S; van de Linde, I B; Wijtten, P J A; Kemp, B; van den Brand, H; Lammers, A

    2016-09-01

    Delayed feed and water access is known to impair growth performance of day old broiler chickens. Although effects of feed access on growth performance and immune function of broilers have been examined before, effects of dietary composition and its potential interaction with feed access are hardly investigated. This experiment aimed to determine whether moment of first feed and water access after hatch and pre-starter composition (0 to 7 days) affect growth rate and humoral immune function in broiler chickens. Direct fed chickens received feed and water directly after placement in the grow-out facility, whilst delayed fed chickens only after 48 h. Direct and delayed fed chickens received a control pre-starter diet, or a diet containing medium chain fatty acids (MCFA) or fish oil. At 21 days, chickens were immunized by injection of sheep red blood cells. The mortality rate depended on an interaction between feed access and pre-starter composition (P=0.014). Chickens with direct feed access fed the control pre-starter diet had a higher risk for mortality than chickens with delayed feed access fed the control pre-starter diet (16.4% v. 4.2%) whereas the other treatment groups were in-between. BW gain and feed intake till 25 days in direct fed chickens were higher compared with delayed fed chickens, whilst gain to feed ratio was lower. Within the direct fed chickens, the control pre-starter diet resulted in the highest BW at 28 days and the MCFA pre-starter diet the lowest (Δ=2.4%), whereas this was opposite for delayed fed chickens (Δ=3.0%; P=0.033). Provision of MCFA resulted in a 4.6% higher BW gain and a higher gain to feed ratio compared with other pre-starter diets, but only during the period it was provided (2 to 7 days). Minor treatment effects were found for humoral immune response by measuring immunoglobulins, agglutination titers, interferon gamma (IFN- γ ), and complement activity. Concluding, current inclusion levels of fish oil (5 g/kg) and MCFA (30 g

  19. 21 CFR 874.5350 - Suction antichoke device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Suction antichoke device. 874.5350 Section 874.5350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5350 Suction antichoke device....

  20. 21 CFR 874.5350 - Suction antichoke device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Suction antichoke device. 874.5350 Section 874.5350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5350 Suction antichoke device....

  1. 21 CFR 874.5350 - Suction antichoke device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Suction antichoke device. 874.5350 Section 874.5350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5350 Suction antichoke device....

  2. 21 CFR 880.5740 - Suction snakebite kit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Suction snakebite kit. 880.5740 Section 880.5740 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5740 Suction snakebite kit....

  3. 21 CFR 880.5740 - Suction snakebite kit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Suction snakebite kit. 880.5740 Section 880.5740 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Therapeutic Devices § 880.5740 Suction snakebite kit....

  4. 21 CFR 878.5040 - Suction lipoplasty system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... (a) Identification. A suction lipoplasty system is a device intended for aesthetic body contouring... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Suction lipoplasty system. 878.5040 Section 878.5040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  5. 21 CFR 878.5040 - Suction lipoplasty system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... (a) Identification. A suction lipoplasty system is a device intended for aesthetic body contouring... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Suction lipoplasty system. 878.5040 Section 878.5040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  6. 21 CFR 878.5040 - Suction lipoplasty system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    .... (a) Identification. A suction lipoplasty system is a device intended for aesthetic body contouring... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Suction lipoplasty system. 878.5040 Section 878.5040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  7. 21 CFR 878.5040 - Suction lipoplasty system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... (a) Identification. A suction lipoplasty system is a device intended for aesthetic body contouring... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Suction lipoplasty system. 878.5040 Section 878.5040 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  8. Transition Flight Experiments on a Swept Wing With Suction

    NASA Technical Reports Server (NTRS)

    Maddalon, D. V.; Collier, F. S., Jr.; Montoya, L. C.; Land, C. K.

    1989-01-01

    Flight experiments were conducted on a 30 degree swept wing with a perforated leading edge by systematically varying the location and amount of suction over a range of Mach number and Reynolds number. Suction was varied chordwise ahead of the front spar from either the front or rear direction by sealing spanwise perforated strips. Transition from laminar to turbulent flow was due to leading edge turbulence contamination or crossflow disturbance growth and/or Tollmien-Schlichting disturbance growth-depending on the test configuration, flight condition, and suction location. A state-of-the-art linear stability theory which accounts for body and streamline curvature and compressibility was used to study the boundary layer stability as suction location and magnitude varied. N-factor correlations with transition location were made for various suction configurations.

  9. Transition flight experiments on a swept wing with suction

    NASA Technical Reports Server (NTRS)

    Maddalon, D. V.; Land, C. K.; Collier, F. S.; Montoya, L. C.

    1989-01-01

    Flight experiments were conducted on a 30 degree swept wing with a perforated leading edge by systematically varying the location and amount of suction over a range of Mach number and Reynolds number. Suction was varied chordwise ahead of the front spar from either the front or rear direction by sealing spanwise perforated strips. Transition from laminar to turbulent flow was due to leading edge turbulence contamination or crossflow disturbance growth and/or Tollmien-Schlichting disturbance growth, depending on the test configuration, flight condition, and suction location. A state-of-the-art linear stability theory which accounts for body and streamline curvature and compressibility was used to study the boundary layer stability as suction location and magnitude varied. N-factor correlations with transition location were made for various suction configurations.

  10. Complete feeds-intensive systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most commercially cultivated fish are raised in high-density culture systems where the assumption is that the contribution of natural foods to the nutrition of the fish is insignificant. Thus, intensively cultured fish must be fed a nutritionally complete feed. A short section on the concept and im...

  11. Do small efficient fish grow into large efficient fish?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feed efficiency is an important trait for cultured fish; more efficient animals not only grow on less feed, but they produce less waste as well. Nevertheless, because individual feed intake is hard to accurately estimate, feed efficiency is a difficult trait to measure, and many factors contribute ...

  12. How to perform open tracheal suction via an endotracheal tube.

    PubMed

    Credland, Nicola

    2016-04-27

    Rationale and key points Tracheal suction involves the removal of pulmonary secretions from the respiratory tract using negative pressure under sterile conditions. Practitioners should be aware of the indications for, and risks associated with, open tracheal suction via an endotracheal tube. ▶ Respiratory assessment of the patient should be carried out to identify when tracheal suction is required. ▶ A suction pressure of 80-120mmHg is recommended, and suction should last no longer than 15 seconds. ▶ Reassurance and support should be given to the patient to minimise any discomfort and distress that might result from tracheal suction. Reflective activity Clinical skills articles can help update your practice and ensure it remains evidence-based. Apply this article to your practice. Reflect on and write a short account of: 1. How you think this article will change your practice when performing open tracheal suction via an endotracheal tube. 2. How you could use this resource to educate your colleagues. Subscribers can upload their reflective accounts at: rcni.com/portfolio . PMID:27191318

  13. Oxygen saturation and secretion weight after endotracheal suctioning.

    PubMed

    Giakoumidakis, Konstantinos; Kostaki, Zoi; Patelarou, Evridiki; Baltopoulos, George; Brokalaki, Hero

    Endotracheal suctioning is a common aspect of nursing care to mechanically-ventilated patients. The aim of this study was to investigate the effects of two suctioning techniques on oxygen saturation (SaO2) and the amount of drained secretions. A quasi-experimental study of 103 mechanically-ventilated patients was conducted from two tertiary hospitals in Greece. Two suctioning techniques were applied to each patient: with normal saline instillation and without. Normal saline instillation was associated with increased secretions' weight (p<0.001) and no significant differences in SaO2 values compared with no instillation. In examining each suctioning technique separately, the use of normal saline instillation was associated with a decrease in SaO2 levels 1 minute (p<0.001) and 15 minutes (p=0.002) after this procedure. In addition, suctioning without normal saline instillation was associated with a decrease in SaO2 1 minute (p<0.001) after the suction. In conclusion, normal saline instillation is related with a negative outcome on patient oxygenation for a prolonged period after the suction and causes the removal of a greater amount of secretions than the applied technique with no instillation. Comparing the two techniques, none is superior to the other resulting from the statistically insignificant comparative differences in SaO2 values. PMID:22241423

  14. [The value of wound drainage with or without suction].

    PubMed

    Schmidt, J; Hasselbach, A; Schnorr, W; Baranek, T; Letsch, R

    2005-11-01

    Even though the discussion for desisting from wound drainage has arisen, this is not reflected in the reality of surgical treatment. In more than 90% of all procedures wound drainage is used. It remains to be proven whether suction drainage actually is superior to gravity drainage in everyday use. In a random study with 200 patients it was proven that suction drainage shows no significant advantage in liquid quantum, haematoma and the frequency of complications. We conclude that the economically favourable gravity drainage can replace the more expensive suction drainage in most cases. PMID:16228157

  15. Centrifugal pumps: which suction specific speeds are acceptable

    SciTech Connect

    Hallam, J.L.

    1982-04-01

    Suction specific speed is an important consideration when purchasing or analyzing centrifugal pumps. There is a direct correlation between this parameter, pump reliability and maintenance expenses. This article demonstrates that in a large Gulf Coast oil refinery, centrifugal pumps with a suction specific speed greater than 11,000 failed at a frequency nearly twice that of centrifugal pumps with suction specific speed less than 11,000. This study consisted primarily of hydrocarbon pumps with an average horsepower of 150 hp. Results may vary some from those found if high energy water pumps are studied. 5 refs.

  16. Development of Cutting and Suction Device with Twist Blade Screw for Minimally Invasive Surgery: Evaluation of Suction Performance.

    PubMed

    Fujii, Yusuke; Suzuki, Takashi; Tamura, Manabu; Muragaki, Yoshihiro; Iseki, Hiroshi

    2015-01-01

    In this study, we aim to develop a narrow-diameter and long-bore device for minimally invasive surgery that achieves the simultaneous cutting and suction of body tissue such as the diseased part of an organ. In this paper, we propose a screw made of a thin metal plate, and we developed a prototype device using this screw. For smooth operation, the suction performance must be superior to the cutting performance. Therefore, we performed experiments and evaluated the suction performance of the developed device assuming the crushed tissue pieces correspond to a highly viscous fluid. From the results, we confirmed that the suction volume is almost proportional to the rotation speed of the screw in the low speed range, and the device has an upper limit of suction volume at a certain rotation speed. Considering practical use, its proportional speed range is suitable for the device controllability of cutting and suction volume, and the size of the device tip needs to be 1 mm or more. Based on these conditions, we are planning to examine the shape of the cutting edge for realizing efficient cutting and suction and we will complete the device. PMID:26132592

  17. Development of Cutting and Suction Device with Twist Blade Screw for Minimally Invasive Surgery: Evaluation of Suction Performance

    PubMed Central

    Fujii, Yusuke; Suzuki, Takashi; Tamura, Manabu; Muragaki, Yoshihiro; Iseki, Hiroshi

    2015-01-01

    In this study, we aim to develop a narrow-diameter and long-bore device for minimally invasive surgery that achieves the simultaneous cutting and suction of body tissue such as the diseased part of an organ. In this paper, we propose a screw made of a thin metal plate, and we developed a prototype device using this screw. For smooth operation, the suction performance must be superior to the cutting performance. Therefore, we performed experiments and evaluated the suction performance of the developed device assuming the crushed tissue pieces correspond to a highly viscous fluid. From the results, we confirmed that the suction volume is almost proportional to the rotation speed of the screw in the low speed range, and the device has an upper limit of suction volume at a certain rotation speed. Considering practical use, its proportional speed range is suitable for the device controllability of cutting and suction volume, and the size of the device tip needs to be 1 mm or more. Based on these conditions, we are planning to examine the shape of the cutting edge for realizing efficient cutting and suction and we will complete the device. PMID:26132592

  18. Controlled trial of a continuous irrigation suction catheter vs conventional intermittent suction catheter in clearing bronchial secretions from ventilated patients.

    PubMed

    Isea, J O; Poyant, D; O'Donnell, C; Faling, L J; Karlinsky, J; Celli, B R

    1993-04-01

    Continuous irrigation-suction catheter (Irri-cath) is a double-lumen device that allows for simultaneous saline solution infusion and aspiration. This system may theoretically be more effective than conventional dry intermittent suction due to its vortex principle. To test this hypothesis, we performed 200 suction maneuvers in 20 ventilated patients. Identically shaped catheters were used in a randomized sequence. For the same individual, we used equal instilled saline solution volume (40 ml), vacuum pressure (-180 cm H2O), and ventilatory parameters. Effectiveness of suction was determined by measuring the total aspirated volume, the dry lyophilized weight of secretion, the corrected dry weight (dry weight-weight of instilled salt), and protein concentration. No difference in heart rate, respiratory frequency, O2 saturation, systemic blood pressure, peak inspiratory pressure, or patient discomfort was found when the two modalities were compared; however, the total volume of secretions collected, the dry weight, the corrected dry weight, and the protein concentration were significantly higher with continuous irrigation suction catheter when compared with the conventional method (p < 0.05). The suction time was shorter with the Irri-cath (p < 0.05). We conclude that the Irri-Cath is more effective than conventional intermittent suction catheter in clearing bronchial secretions in patients on mechanical ventilation. PMID:8131470

  19. Optically transparent multi-suction electrode arrays

    PubMed Central

    Nagarah, John M.; Stowasser, Annette; Parker, Rell L.; Asari, Hiroki; Wagenaar, Daniel A.

    2015-01-01

    Multielectrode arrays (MEAs) allow for acquisition of multisite electrophysiological activity with submillisecond temporal resolution from neural preparations. The signal to noise ratio from such arrays has recently been improved by substrate perforations that allow negative pressure to be applied to the tissue; however, such arrays are not optically transparent, limiting their potential to be combined with optical-based technologies. We present here multi-suction electrode arrays (MSEAs) in quartz that yield a substantial increase in the detected number of units and in signal to noise ratio from mouse cortico-hippocampal slices and mouse retina explants. This enables the visualization of stronger cross correlations between the firing rates of the various sources. Additionally, the MSEA's transparency allows us to record voltage sensitive dye activity from a leech ganglion with single neuron resolution using widefield microscopy simultaneously with the electrode array recordings. The combination of enhanced electrical signals and compatibility with optical-based technologies should make the MSEA a valuable tool for investigating neuronal circuits. PMID:26539078

  20. 21 CFR 878.4780 - Powered suction pump.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4780 Powered suction pump. (a... support system. The device may be used during surgery in the operating room or at the patient's...

  1. 21 CFR 878.4780 - Powered suction pump.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4780 Powered suction pump. (a... support system. The device may be used during surgery in the operating room or at the patient's...

  2. 21 CFR 878.4780 - Powered suction pump.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4780 Powered suction pump. (a... support system. The device may be used during surgery in the operating room or at the patient's...

  3. 21 CFR 878.4780 - Powered suction pump.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4780 Powered suction pump. (a... support system. The device may be used during surgery in the operating room or at the patient's...

  4. 21 CFR 878.4780 - Powered suction pump.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4780 Powered suction pump. (a... support system. The device may be used during surgery in the operating room or at the patient's...

  5. Analysis of retinol, 3-hydroxyretinol and 3,4-didehydroretinol in North American farm-raised freshwater fish liver, muscle and feed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vitamin A (retinol; ROL) is an essential micronutrient in fish, vital for vision and cell growth. Freshwater fish species also synthesize uncommon forms of VA, such as 3,4-didehydrotinol (DROL) and 3-hydroxyretinol (3ROL) that have biological activity. However, little information is available abou...

  6. Fishmeal-free Atlantic salmon feed formulation shows promise - Joint research between TCFFI, USDA and EWOS uses new diet for post-smolt to food-size fish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The 2 MT/week of Atlantic salmon that The Conservation Fund Freshwater Institute provided to market in March and April of 2016 were fed a custom diet during nearly 90% of their growth that met the following sustainability criteria: - Fishmeal free - GMO free - Zero wild fish in: fish out according t...

  7. The generation of side force by distributed suction

    NASA Astrophysics Data System (ADS)

    Roberts, Leonard; Hong, John

    1993-05-01

    This report provides an approximate analysis of the generation of side force on a cylinder placed horizontal to the flow direction by the application of distributed suction on the rearward side of the cylinder. Relationships are derived between the side force coefficients and the required suction coefficients necessary to maintain attached flow on one side of the cylinder, thereby inducing circulation around the cylinder and a corresponding side force.

  8. Growth and Feed Efficiency of Juvenile Channel Catfish Ictalurus punctatus Fed Diets Containing Various Levels of Fish Meal at Different Water Temperatures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unlike warm-blooded animals, channel catfish do not feed consistently when water temperatures are below 20°C and generally stop eating at temperatures of 10°C and below. Many catfish producers choose not to feed during winter months for various reasons, one of which is that it is difficult to see a...

  9. Differing ERP patterns caused by suction and puff stimuli.

    PubMed

    Choi, Mi-Hyun; Kim, Hyung-Sik; Baek, Ji-Hye; Lee, Jung-Chul; Park, Sung-Jun; Jeong, Ul-Ho; Gim, Seon-Young; You, Ji Hye; Kim, Sung-Pil; Lim, Dae-Woon; Kim, Hyun-Jun; Chung, Soon-Cheol

    2015-05-01

    The present study compared event-related potential (ERP) patterns for two stimuli types, puff and suction, by applying these stimuli to the fingers; ERP patterns for the two stimuli were compared at C3, an area related to somatosensory perception, and at FC5, an area related to motor function. Participants were 12 healthy males in their 20s (mean age=23.1±2.0 years). One session consisted of a Control Phase (3s), a Stimulation Phase (3s), and a Rest Phase (9s). During the Stimulation Phase, a 4-psi suction or puff stimulus was applied to the first joint of the right index finger. After completion of the session, a subjective magnitude test was presented. In all phases, electroencephalography signals were recorded. We extracted maximum positive amplitude and minimum negative amplitude as well as relevant latency values for C3 and FC5 signals. Suction and puff stimuli had similar subjective magnitude scores. For both C3 and FC5, the maximum and minimum amplitude latency was reached earlier for the suction stimulus than for the puff stimulus. In conclusion, when suction and puff stimuli of the same intensity were applied to the fingers, the suction stimulus caused a more sensitive response in the somatosensory area (C3) and motor area (FC5) than did the puff stimulus. PMID:25823997

  10. Endotracheal suctioning in intubated newborns: an integrative literature review

    PubMed Central

    Gonçalves, Roberta Lins; Tsuzuki, Lucila Midori; Carvalho, Marcos Giovanni Santos

    2015-01-01

    Evidence-based practices search for the best available scientific evidence to support problem solving and decision making. Because of the complexity and amount of information related to health care, the results of methodologically sound scientific papers must be integrated by performing literature reviews. Although endotracheal suctioning is the most frequently performed invasive procedure in intubated newborns in neonatal intensive care units, few Brazilian studies of good methodological quality have examined this practice, and a national consensus or standardization of this technique is lacking. Therefore, the purpose of this study was to review secondary studies on the subject to establish recommendations for endotracheal suctioning in intubated newborns and promote the adoption of best-practice concepts when conducting this procedure. An integrative literature review was performed, and the recommendations of this study are to only perform endotracheal suctioning in newborns when there are signs of tracheal secretions and to avoid routinely performing the procedure. In addition, endotracheal suctioning should be conducted by at least two people, the suctioning time should be less than 15 seconds, the negative suction pressure should be below 100 mmHg, and hyperoxygenation should not be used on a routine basis. If indicated, oxygenation is recommended with an inspired oxygen fraction value that is 10 to 20% greater than the value of the previous fraction, and it should be performed 30 to 60 seconds before, during and 1 minute after the procedure. Saline instillation should not be performed routinely, and the standards for invasive procedures must be respected. PMID:26465249

  11. Endotracheal suctioning in intubated newborns: an integrative literature review.

    PubMed

    Gonçalves, Roberta Lins; Tsuzuki, Lucila Midori; Carvalho, Marcos Giovanni Santos

    2015-01-01

    Evidence-based practices search for the best available scientific evidence to support problem solving and decision making. Because of the complexity and amount of information related to health care, the results of methodologically sound scientific papers must be integrated by performing literature reviews. Although endotracheal suctioning is the most frequently performed invasive procedure in intubated newborns in neonatal intensive care units, few Brazilian studies of good methodological quality have examined this practice, and a national consensus or standardization of this technique is lacking. Therefore, the purpose of this study was to review secondary studies on the subject to establish recommendations for endotracheal suctioning in intubated newborns and promote the adoption of best-practice concepts when conducting this procedure. An integrative literature review was performed, and the recommendations of this study are to only perform endotracheal suctioning in newborns when there are signs of tracheal secretions and to avoid routinely performing the procedure. In addition, endotracheal suctioning should be conducted by at least two people, the suctioning time should be less than 15 seconds, the negative suction pressure should be below 100 mmHg, and hyperoxygenation should not be used on a routine basis. If indicated, oxygenation is recommended with an inspired oxygen fraction value that is 10 to 20% greater than the value of the previous fraction, and it should be performed 30 to 60 seconds before, during and 1 minute after the procedure. Saline instillation should not be performed routinely, and the standards for invasive procedures must be respected. PMID:26465249

  12. A PHYSIOLOGICALLY BASED TOXICOKINETIC MODEL FOR DIETARY UPTAKE OF HYDROPHOBIC ORGANIC COMPOUNDS BY FISH: I. FEEDING STUDIES WITH 2,2',5,5'-TETRACHLOROBIPHENYL

    EPA Science Inventory

    A physiologically-based toxicokinetic (PBTK) model was developed to describe dietary uptake of hydrophobic organic compounds by fish. The gastrointestinal (GI) tract was modeled using four compartments corresponding to the stomach, pyloric ceca, upper intestine, and lower intesti...

  13. Suction-generated noise in an anatomic silicon ear model.

    PubMed

    Luxenberger, Wolfgang; Lahousen, T; Walch, C

    2012-10-01

    The objectives of this study were to evaluate noise levels generated during micro-suction aural toilet using an anatomic silicon ear model. It is an experimental study. In an anatomic ear model made of silicone, the eardrum was replaced by a 1-cm diameter microphone of a calibrated sound-level measuring device. Ear wax was removed using the sucker of a standard ENT treatment unit (Atmos Servant 5(®)). Mean and peak sound levels during the suction procedure were recorded with suckers of various diameters (Fergusson-Frazier 2.7-4 mm as well as Rosen 1.4-2.5 mm). Average noise levels during normal suction in a distance of 1 cm in front of the eardrum ranged between 97 and 103.5 dB(A) (broadband noise). Peak noise levels reached 118 dB(A). During partial obstruction of the sucker by cerumen or dermal flakes, peak noise levels reached 146 dB(A). Peak noise levels observed during the so-called clarinet phenomena were independent of the diameter or type of suckers used. Although micro-suction aural toilet is regarded as an established, widespread and usually safe method to clean the external auditory canal, some caution seems advisable. The performance of long-lasting suction periods straight in front of the eardrum without sound-protecting earwax between sucker and eardrum should be avoided. In particular, when clarinet phenomena are occurring (as described above), the suction procedure should be aborted immediately. In the presence of dermal flakes blocking the auditory canal, cleaning with micro-forceps or other non-suctioning instruments might represent a reasonable alternative. PMID:22740154

  14. Dielectric elastomer actuators for octopus inspired suction cups.

    PubMed

    Follador, M; Tramacere, F; Mazzolai, B

    2014-01-01

    Suction cups are often found in nature as attachment strategy in water. Nevertheless, the application of the artificial counterpart is limited by the dimension of the actuators and their usability in wet conditions. A novel design for the development of a suction cup inspired by octopus suckers is presented. The main focus of this research was on the modelling and characterization of the actuation unit, and a first prototype of the suction cup was realized as a proof of concept. The actuation of the suction cup is based on dielectric elastomer actuators. The presented device works in a wet environment, has an integrated actuation system, and is soft. The dimensions of the artificial suction cups are comparable to proximal octopus suckers, and the attachment mechanism is similar to the biological counterpart. The design approach proposed for the actuator allows the definition of the parameters for its development and for obtaining a desired pressure in water. The fabricated actuator is able to produce up to 6 kPa of pressure in water, reaching the maximum pressure in less than 300 ms. PMID:25253019

  15. Octopus-like suction cups: from natural to artificial solutions.

    PubMed

    Tramacere, F; Follador, M; Pugno, N M; Mazzolai, B

    2015-06-01

    Octopus suckers are able to attach to all nonporous surfaces and generate a very strong attachment force. The well-known attachment features of this animal result from the softness of the sucker tissues and the surface morphology of the portion of the sucker that is in contact with objects or substrates. Unlike artificial suction cups, octopus suckers are characterized by a series of radial grooves that increase the area subjected to pressure reduction during attachment. In this study, we constructed artificial suction cups with different surface geometries and tested their attachment performances using a pull-off setup. First, smooth suction cups were obtained for casting; then, sucker surfaces were engraved with a laser cutter. As expected, for all the tested cases, the engraving treatment enhanced the attachment performance of the elastomeric suction cups compared with that of the smooth versions. Moreover, the results indicated that the surface geometry with the best attachment performance was the geometry most similar to octopus sucker morphology. The results obtained in this work can be utilized to design artificial suction cups with higher wet attachment performance. PMID:25970079

  16. Rotary blood pump control strategy for preventing left ventricular suction.

    PubMed

    Wang, Yu; Koenig, Steven C; Slaughter, Mark S; Giridharan, Guruprasad A

    2015-01-01

    The risk for left ventricular (LV) suction while maintaining adequate perfusion over a range of physiologic conditions during continuous flow LV assist device (LVAD) support is a significant clinical concern. To address this challenge, we developed a suction prevention and physiologic control (SPPC) algorithm for use with axial and centrifugal LVADs. The SPPC algorithm uses two gain-scheduled, proportional-integral controllers that maintain a differential pump speed (ΔRPM) above a user-defined threshold to prevent LV suction, while maintaining an average reference differential pressure (ΔP) between the LV and aorta to provide physiologic perfusion. Efficacy and robustness of the proposed algorithm were evaluated in silico during simulated rest and exercise test conditions for (1) ΔP/ΔRPM excessive setpoint (ES); (2) rapid eightfold increase in pulmonary vascular resistance (PVR); and (3) ES and PVR. Hemodynamic waveforms (LV pressure and volume; aortic pressure and flow) were simulated and analyzed to identify suction event(s), quantify total flow output (pump + cardiac output), and characterize the performance of the SPPC algorithm. The results demonstrated that the proposed SPPC algorithm prevented LV suction while maintaining physiologic perfusion for all simulated test conditions, and warrants further investigation in vivo. PMID:25248043

  17. Feeding mechanics and bite force modelling of the skull of Dunkleosteus terrelli, an ancient apex predator.

    PubMed

    Anderson, Philip S L; Westneat, Mark W

    2007-02-22

    Placoderms are a diverse group of armoured fishes that dominated the aquatic ecosystems of the Devonian Period, 415-360 million years ago. The bladed jaws of predators such as Dunkleosteus suggest that these animals were the first vertebrates to use rapid mouth opening and a powerful bite to capture and fragment evasive prey items prior to ingestion. Here, we develop a biomechanical model of force and motion during feeding in Dunkleosteus terrelli that reveals a highly kinetic skull driven by a unique four-bar linkage mechanism. The linkage system has a high-speed transmission for jaw opening, producing a rapid expansion phase similar to modern fishes that use suction during prey capture. Jaw closing muscles power an extraordinarily strong bite, with an estimated maximal bite force of over 4400 N at the jaw tip and more than 5300 N at the rear dental plates, for a large individual (6 m in total length). This bite force capability is the greatest of all living or fossil fishes and is among the most powerful bites in animals. PMID:17443970

  18. Safety System for Controlling Fluid Flow into a Suction Line

    NASA Technical Reports Server (NTRS)

    England, John Dwight (Inventor); Kelley, Anthony R. (Inventor); Cronise, Raymond J. (Inventor)

    2015-01-01

    A safety system includes a sleeve fitted within a pool's suction line at the inlet thereof. An open end of the sleeve is approximately aligned with the suction line's inlet. The sleeve terminates with a plate that resides within the suction line. The plate has holes formed therethrough. A housing defining a plurality of distinct channels is fitted in the sleeve so that the distinct channels lie within the sleeve. Each of the distinct channels has a first opening on one end thereof and a second opening on another end thereof. The second openings reside in the sleeve. Each of the distinct channels is at least approximately three feet in length. The first openings are in fluid communication with the water in the pool, and are distributed around a periphery of an area of the housing that prevents coverage of all the first openings when a human interacts therewith.

  19. Design considerations of advanced supercritical low drag suction airfoils

    NASA Technical Reports Server (NTRS)

    Pfenninger, W.; Reed, H. L.; Dagenhart, J. R.

    1980-01-01

    Supercritical low drag suction laminar flow airfoils were laid out for shock-free flow at design freestream Mach = 0.76, design lift coefficient = 0.58, and t/c = 0.13. The design goals were the minimization of suction laminarization problems and the assurance of shock-free flow at freestream Mach not greater than design freestream Mach (for design lift coefficient) as well as at lift coefficient not greater than design lift coefficient (for design freestream Mach); this involved limiting the height-to-length ratio of the supersonic zone at design to 0.35. High design freestream Mach numbers result with extensive supersonic flow (over 80% of the chord) on the upper surface, with a steep Stratford-type rear pressure rise with suction, as well as by carrying lift essentially in front- and rear-loaded regions of the airfoil with high static pressures on the carved out front and rear lower surface.

  20. Feeding mice with diets containing mercury-contaminated fish flesh from French Guiana: a model for the mercurial intoxication of the Wayana Amerindians

    PubMed Central

    Bourdineaud, Jean-Paul; Bellance, Nadège; Bénard, Giovani; Brèthes, Daniel; Fujimura, Masatake; Gonzalez, Patrice; Marighetto, Aline; Maury-Brachet, Régine; Mormède, Cécile; Pédron, Vanessa; Philippin, Jean-Nicolas; Rossignol, Rodrigue; Rostène, William; Sawada, Masumi; Laclau, Muriel

    2008-01-01

    Background In 2005, 84% of Wayana Amerindians living in the upper marshes of the Maroni River in French Guiana presented a hair mercury concentration exceeding the limit set up by the World Health Organization (10 μg/g). To determine whether this mercurial contamination was harmful, mice have been fed diets prepared by incorporation of mercury-polluted fish from French Guiana. Methods Four diets containing 0, 0.1, 1, and 7.5% fish flesh, representing 0, 5, 62, and 520 ng methylmercury per g, respectively, were given to four groups of mice for a month. The lowest fish regimen led to a mercurial contamination pressure of 1 ng mercury per day per g of body weight, which is precisely that affecting the Wayana Amerindians. Results The expression of several genes was modified with mercury intoxication in liver, kidneys, and hippocampus, even at the lowest tested fish regimen. A net genetic response could be observed for mercury concentrations accumulated within tissues as weak as 0.15 ppm in the liver, 1.4 ppm in the kidneys, and 0.4 ppm in the hippocampus. This last value is in the range of the mercury concentrations found in the brains of chronically exposed patients in the Minamata region or in brains from heavy fish consumers. Mitochondrial respiratory rates showed a 35–40% decrease in respiration for the three contaminated mice groups. In the muscles of mice fed the lightest fish-containing diet, cytochrome c oxidase activity was decreased to 45% of that of the control muscles. When mice behavior was assessed in a cross maze, those fed the lowest and mid-level fish-containing diets developed higher anxiety state behaviors compared to mice fed with control diet. Conclusion We conclude that a vegetarian diet containing as little as 0.1% of mercury-contaminated fish is able to trigger in mice, after only one month of exposure, disorders presenting all the hallmarks of mercurial contamination. PMID:18959803

  1. Cohesive suction-cup force in cell separation dynamics

    NASA Astrophysics Data System (ADS)

    Vasseur, H.

    2010-07-01

    When an external pulling force is applied onto a cell stuck to its substrate, a reacting "suction-cup" force, due to the slow penetration of the surrounding fluid between the cell and the substrate, opposes to the separation. It can overcome other known adhesive forces when the process is sufficiently violent (typically 105 N/m2). The physical origin of this effect may be compared with that leaning a suction-cup against a bathroom wall. We address the consequences of this effect on i) the separation energy, ii) the fluid motion surrounding the cell, and iii) the inhibition of cell motion.

  2. Premaxillary movements in cyprinodontiform fishes: an unusual protrusion mechanism facilitates "picking" prey capture.

    PubMed

    Ferry-Graham, Lara A; Gibb, Alice C; Hernandez, L Patricia

    2008-01-01

    Premaxillary protrusion is hypothesized to confer a number of feeding advantages to teleost fishes; however, most proposed advantages relate to enhanced stealth or suction production during prey capture. Cyprinodontiformes exhibit an unusual form of premaxillary protrusion where the descending process of the premaxilla does not rotate anteriorly to occlude the sides of the open mouth during prey capture. Instead, the premaxilla is protruded such that it gives the impression of a beak during prey capture. We quantified premaxillary kinematics during feeding in four cyprinodontiform taxa and compared them with three percomorph taxa to identify any performance consequences of this protrusion mechanism. Individual prey capture events were recorded using digital high-speed video at 250-500 frames per second (n >or= 4 individuals, >or= 4 strikes per individual). Species differed in the timing of movement and the maximum displacement of the premaxilla during the gape cycle and in the contribution of the premaxilla to jaw closing. Cyprinodontiform taxa produced less premaxillary protrusion than the percomorph taxa, and were consistently slower in the time to maximum gape. Further, it appears cyprinodontiforms can alter the contribution of the premaxilla to mouth closure on an event-specific basis. We were able to demonstrate that, within at least one species, this variability is associated with the location of the prey (bottom vs. water column). Cyprinodontiform upper jaw movements likely reflect increased dexterity associated with a foraging ecology where prey items are "picked" from a variety of locations: the bottom, water column, or surface. We postulate that dexterity requires slow, precisely controlled jaw movements; thus, may be traded off for some aspects of suction-feeding performance, such as protrusion distance and speed. PMID:18619823

  3. The relative importance of mangroves and seagrass beds as feeding habitats for resident and transient fishes from Florida and Belize:: evidence from dietary and stable isotope analyses

    EPA Science Inventory

    In the western Atlantic region, the contribution of mangrove food-sources to fish diets has been considered of more limited importance then previously expected due to their constant flooding and proximity to adjacent coastal habitats such as seagrass beds which provide potential ...

  4. By-products from seafood processing for aquaculture and animal feeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alaska fish processing by-products can be used to make fertilizer and other products; however, most of the fish by-products produced in large shore-side fish processing operations are used to make fish meal and fish oil. Primary uses of fish meals and oils are as aquaculture feed ingredient for fish...

  5. Fabrication of a Feeding Obturator for Infants.

    PubMed

    Hansen, Paul A; Cook, N Blaine; Ahmad, Omaid

    2016-03-01

    Large clefts in the lip and palate are common congenital anomalies. If the cleft palate is large enough, conventional feeding techniques may not provide proper nutrition for the infant. Feeding obturators will aid in the ability of the infant to attain suction and help the infant to feed adequately. It is necessary for the infant to have sustained weight gain prior to surgery to correct the cleft lip and/or palate. Fabrication of an infant feeding obturator is a simple technique using materials found in every dental office. An impression is made using modeling plastic impression compound. This impression is relined using irreversible hydrocolloid, and the resulting cast is used to enable a vacuum-formed obturator to be fabricated. The vacuum-formed obturator is smoothed and adjusted in the infant's mouth to ensure closure of the palate but allows pace posteriorly to allow normal breathing. The resulting obturator is well retained in the infant's mouth, allowing feeding. PMID:26237189

  6. Feeding kinematics and performance of basal otariid pinnipeds, Steller sea lions and northern fur seals: implications for the evolution of mammalian feeding.

    PubMed

    Marshall, Christopher D; Rosen, David A S; Trites, Andrew W

    2015-10-01

    Feeding performance studies can address questions relevant to feeding ecology and evolution. Our current understanding of feeding mechanisms for aquatic mammals is poor. Therefore, we characterized the feeding kinematics and performance of five Steller sea lions (Eumetopias jubatus) and six northern fur seals (Callorhinus ursinus). We tested the hypotheses that both species use suction as their primary feeding mode, and that rapid jaw opening was related to suction generation. Steller sea lions used suction as their primary feeding mode, but also used a biting feeding mode. In contrast, northern fur seals only used a biting feeding mode. Kinematic profiles of Steller sea lions were all indicative of suction feeding (i.e. a small gape, small gape angle, large depression of the hyolingual apparatus and lip pursing). However, jaw opening as measured by gape angle opening velocity (GAOV) was relatively slow in Steller sea lions. In contrast to Steller sea lions, the GAOV of northern fur seals was extremely fast, but their kinematic profiles indicated a biting feeding mode (i.e. northern fur seals exhibited a greater gape, a greater gape angle and minimal depression of the hyolingual apparatus compared with Steller sea lions). Steller sea lions produced both subambient and suprambient pressures at 45 kPa. In contrast, northern fur seals produced no detectable pressure measurements. Steller sea lions have a broader feeding repertoire than northern fur seals, which likely enables them to feed on a greater variety of prey, in more diverse habitats. Based on the basal phylogenetic position of northern fur seals, craniodental morphological data of the Callorhinus lineage, and the performance data provided in this study, we suggest that northern fur seals may be exhibiting their ancestral feeding mode. PMID:26449976

  7. Vulvar myiasis following suction and evacuation for incomplete abortion.

    PubMed

    Singh, Anju; Goel, Bharti; Rani, Shikha

    2015-07-01

    Myiasis is caused by fly larva capable of penetrating healthy or necrotic tissue, usually in tropical and subtropical countries. The involvement of an exposed area is common; however it may very rarely involve the genital region. We present a rare case of vulvar myiasis which occurred after suction and evacuation performed for incomplete abortion. PMID:25740831

  8. Dual-durometer soft suction foot robot for concrete inspection

    NASA Astrophysics Data System (ADS)

    Huston, Dryver; Burns, Dylan; Gardner-Morse, John; Montane, Paul; Angola, Enrique

    2014-03-01

    Climbing on concrete, masonry and brick with automated machines is difficult due to the uneven surfaces that prevent getting a good grip. This paper describes developments in using dual-durometer pneumatic suction feet for gripping onto concrete surfaces as part of a multi-legged robotic climbing system for inspecting concrete structures with vertical walls. The dual durometer technique presents a compliant suction tip to the concrete thereby producing a good seal against an irregular surface, and stiff component to deliver the structural rigidity needed for walking and climbing. Individually actuated pneumatic Venturi vacuum generators provide the suction from positive pneumatic pressure in a manner that is robust against leaks that cause the systemic vacuum collapse that can plague other vacuum configurations. The feet are attached to a six-legged robot that with a nominal floor walking capability and gait. Climbing a wall requires modification to leg actuation and gait, along with suction feet. System design, integration, concrete wall climbing performance and sensor deployment in the form of a lightweight ground penetrating radar system are presented.

  9. 21 CFR 874.5350 - Suction antichoke device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... asphyxiation to the patient. (b) Classification. Class III. (c) Date PMA or notice of completion of PDP is required. A PMA or a notice of completion of a PDP for a device is required to be filed with the Food and... suction antichoke device shall have an approved PMA or declared completed PDP in effect before...

  10. 21 CFR 874.5350 - Suction antichoke device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... asphyxiation to the patient. (b) Classification. Class III. (c) Date PMA or notice of completion of PDP is required. A PMA or a notice of completion of a PDP for a device is required to be filed with the Food and... suction antichoke device shall have an approved PMA or declared completed PDP in effect before...

  11. Teaching Self-Administration of Suctioning to Children with Tracheostomies.

    ERIC Educational Resources Information Center

    Derrickson, Janice G.; And Others

    1991-01-01

    Four children (ages 5-8) with tracheostomies were taught to self-administer a suctioning procedure via doll-centered simulations. Performance of all children improved as a function of training; skill maintenance was demonstrated during followup; and participants revealed high levels of satisfaction with outcomes. (Author/JDD)

  12. Trophic relationships, feeding habits and seasonal dietary changes in an intertidal rockpool fish assemblage in the Gulf of Cadiz (NE Atlantic)

    NASA Astrophysics Data System (ADS)

    Compaire, Jesus C.; Cabrera, Remedios; Gómez-Cama, Carmen; Soriguer, Milagrosa C.

    2016-06-01

    This paper describes the use of resources and diet of nine resident fish species in the rocky intertidal zone of the Gulf of Cadiz and examines whether their populations are affected by trophic competition. A stomach content analysis of the nine species revealed that only one was herbivorous (Parablennius sanguinolentus), while the rest were mainly carnivorous (Gobius bucchichi, Gobius cobitis, Gobius paganellus, Zebrus zebrus, Salaria pavo, Lepadogaster lepadogaster, Scorpaena porcus and Tripterygion tripteronotum). The most frequently consumed prey were amphipods, isopods, polychaetes, decapods, chironomids, tanaidaceans, gastropods, copepods, cumaceans and ostracods. In most species, the occurrence of polychaetes and molluscs was higher in the cold season, whereas that of isopods, decapods, chironomids and fish increased in the warm season. In general, larger specimens consumed larger prey, with an increase in the occurrence of isopods, decapods and fish. An analysis of trophic niche breadth defined G. cobitis as generalist, G. bucchichi as opportunist and S. porcus as specialist, whereas the values obtained for the other species did not indicate a clearly defined strategy. Low diet overlap values and the segregation observed in several analyses indicated an adequate distribution of resources.

  13. 21 CFR 880.6740 - Vacuum-powered body fluid suction apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vacuum-powered body fluid suction apparatus. 880... Personal Use Miscellaneous Devices § 880.6740 Vacuum-powered body fluid suction apparatus. (a) Identification. A vacuum-powered body fluid suction apparatus is a device used to aspirate, remove, or...

  14. 21 CFR 880.6740 - Vacuum-powered body fluid suction apparatus.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vacuum-powered body fluid suction apparatus. 880... Personal Use Miscellaneous Devices § 880.6740 Vacuum-powered body fluid suction apparatus. (a) Identification. A vacuum-powered body fluid suction apparatus is a device used to aspirate, remove, or...

  15. 21 CFR 880.6740 - Vacuum-powered body fluid suction apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vacuum-powered body fluid suction apparatus. 880... Personal Use Miscellaneous Devices § 880.6740 Vacuum-powered body fluid suction apparatus. (a) Identification. A vacuum-powered body fluid suction apparatus is a device used to aspirate, remove, or...

  16. 21 CFR 880.6740 - Vacuum-powered body fluid suction apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vacuum-powered body fluid suction apparatus. 880... Personal Use Miscellaneous Devices § 880.6740 Vacuum-powered body fluid suction apparatus. (a) Identification. A vacuum-powered body fluid suction apparatus is a device used to aspirate, remove, or...

  17. 21 CFR 880.6740 - Vacuum-powered body fluid suction apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vacuum-powered body fluid suction apparatus. 880... Personal Use Miscellaneous Devices § 880.6740 Vacuum-powered body fluid suction apparatus. (a) Identification. A vacuum-powered body fluid suction apparatus is a device used to aspirate, remove, or...

  18. Compressor bleed cooling fluid feed system

    DOEpatents

    Donahoo, Eric E; Ross, Christopher W

    2014-11-25

    A compressor bleed cooling fluid feed system for a turbine engine for directing cooling fluids from a compressor to a turbine airfoil cooling system to supply cooling fluids to one or more airfoils of a rotor assembly is disclosed. The compressor bleed cooling fluid feed system may enable cooling fluids to be exhausted from a compressor exhaust plenum through a downstream compressor bleed collection chamber and into the turbine airfoil cooling system. As such, the suction created in the compressor exhaust plenum mitigates boundary layer growth along the inner surface while providing flow of cooling fluids to the turbine airfoils.

  19. Ontogenetic differences in the feeding biomechanics of oviparous and viviparous caecilians (Lissamphibia: Gymnophiona).

    PubMed

    Kleinteich, Thomas

    2010-10-01

    Caecilians have a unique dual jaw-closing system in that jaw closure is driven by the ancestral jaw-closing muscles (mm. levatores mandibulae) plus a secondarily recruited hyobranchial muscle (m. interhyoideus posterior). There is a variety of feeding habits (suction feeding, skin feeding, intrauterine scraping, and biting) during ontogeny that relate to reproductive modes in different caecilian species. This study examines the cranial biomechanics of caecilians in the suction-feeding larva of Ichthyophis cf. kohtaoensis, in the embryo and juvenile of the skin-feeding Boulengerula taitana, and in a newborn of the intrauterine feeder Typhlonectes natans. A lever arm model was applied to calculate effective mechanical advantages of jaw-closing muscles over gape angles and to predict total bite force in developing caecilians. In I. cf. kohtaoensis, Notable differences were found in the larval jaw-closing system compared to that of the adult. The suction-feeding larva of I. cf. kohtaoensis has comparatively large mm. levatores mandibulae that insert with an acute muscle fiber angle to the lower jaw and a m. interhyoideus posterior that has its optimal leverage at small gape angles. Conversely, the skin-feeding juvenile of B. taitana and the neonate T. natans are very similar in the feeding parameters considered herein compared to adult caecilians. Some ontogenetic variation in the feeding system of B. taitana before the onset of feeding was present. This study contributes to our understanding of the functional demands that feeding habits put on the development of cranial structures. PMID:20952171

  20. Bioaccumulation of dioxin-like PCBs and PBDEs by detritus-feeding fish in the Rio de la Plata estuary, Argentina.

    PubMed

    Cappelletti, N; Speranza, E; Tatone, L; Astoviza, M; Migoya, M C; Colombo, J C

    2015-05-01

    A comparative analysis of bioaccumulation behavior of dioxin-like polychlorinated biphenyls (dlPCBs) and polybrominated biphenyl ethers (PBDEs) was conducted involving simultaneous measurements in settling particles and a detritivorous fish (Sabalo, Prochilodus linneatus) collected in the sewage impacted Buenos Aires coastal area. Focalization of dlPCBs and PBDEs along the detritus food chain is reflected by a 30-40-fold increase of dry weight PBDE and dlPCB concentrations from settling particles to fish (1.8 ± 1.0 to 58 ± 31 and 6.8 ± 3.9 to 281 ± 155 ng g(-1) dry weight (dw), respectively). In this transference, dlPCB congeners presented more conservative patterns than those of PBDEs, basically due to debromination of BDE 99 and 153 to BDE 47 in fish. Lipid/organic carbon-based biota-sediment accumulation factors (BSAFs) ranged between 5 and 20 (7.3 ± 3.0 and 16 ± 8.0 for PBDEs and dlPCBs). Congener-specific BSAF of dlPCBs suggested a lower bioavailability of more planar non-ortho-PCB versus mono-ortho-PCB suggesting higher affinity to organic matter. BSAFs of PBDEs differed markedly among bromine homolog groups, supporting the biotransformation-formation from higher brominated to lighter congeners. The log BSAFs-log K OW relationship of dlPCBs and PBDEs presented a parabolic pattern maximizing at log K OW 6-7, but PBDE curve differs reflecting biotransformation processes. PMID:25501540

  1. Suppression of vortex-induced vibration of a circular cylinder using suction-based flow control

    NASA Astrophysics Data System (ADS)

    Chen, Wen-Li; Xin, Da-Bo; Xu, Feng; Li, Hui; Ou, Jin-Ping; Hu, Hui

    2013-10-01

    In the present study, a flow control method is employed to mitigate vortex-induced vibration (VIV) of a circular cylinder by using a suction flow method. The VIV of a circular cylinder was first reproduced in a wind tunnel by using a spring-mass system. The time evolution of the cylinder oscillation and the time histograms of the surface pressures of 119 taps in four sections of the circular cylinder model were measured during the wind tunnel experiments. Four steady suction flow rates were used to investigate the effectiveness of the suction control method to suppress VIV of the circular cylinder. The vibration responses, the mean and fluctuating pressure coefficients, and the resultant aerodynamic force coefficients of the circular cylinder under the suction flow control are analyzed. The measurement results indicate clearly that the steady suction flow control method exhibits excellent control effectiveness and can distinctly suppress the VIV by dramatically reducing the amplitudes of cylinder vibrations, fluctuating pressure coefficients and lift coefficients of the circular cylinder model. By comparing the test cases with different suction flow rates, it is found that there exists an optimal suction flow rate for the maximum VIV control. The cases with higher suction flow rates do not necessarily behave better than those with lower suction flow rates. With the experimental setting used in the present study, the suction flow control method is found to behave better for VIV suppression when the ratio of the suction flow velocity to the oncoming flow velocity is less than one.

  2. Evaluation of Karl Storz CMAC Tip™ Device Versus Traditional Airway Suction in a Cadaver Model

    PubMed Central

    Lipe, Demis N.; Lindstrom, Randi; Tauferner, Dustin; Mitchell, Christopher; Moffett, Peter

    2014-01-01

    Introduction We compared the efficacy of Karl Storz CMAC Tip™ with inline suction to CMAC with traditional suction device in cadaveric models simulating difficult airways, using media mimicking pulmonary edema and vomit. Methods This was a prospective, cohort study in which we invited emergency medicine faculty and residents to participate. Each participant intubated 2 cadavers (one with simulated pulmonary edema and one with simulated vomit), using CMAC with inline suction and CMAC with traditional suction. Thirty emergency medicine providers performed 4 total intubations each in a crossover trial comparing the CMAC with inline suction and CMAC with traditional suction. Two intubations were performed with simulated vomit and two with simulated pulmonary edema. The primary outcome was time to successful intubation; and the secondary outcome was proportion of successful intubation. Results The median time to successful intubation using the CMAC with inline suction versus traditional suction in the pulmonary edema group was 29s and 30s respectively (p=0.54). In the vomit simulation, the median time to successful intubation was 40s using the CMAC with inline suction and 41s using the CMAC with traditional suction (p=0.70). There were no significant differences in time to successful intubation between the 2 devices. Similarly, the proportions of successful intubation were also not statistically significant between the 2 devices. The proportions of successful intubations using the inline suction were 96.7% and 73.3%, for the pulmonary edema and vomit groups, respectively. Additionally using the handheld suction device, the proportions for the pulmonary edema and vomit group were 100% and 66.7%, respectively. Conclusion CMAC with inline suction was no different than CMAC with traditional suction and was associated with no statistically significant differences in median time to intubation or proportion of successful intubations. PMID:25035766

  3. Endotracheal and upper airways suctioning: changes in newborns' physiological parameters.

    PubMed

    Barbosa, Andréa Lopes; Cardoso, Maria Vera Lúcia Moreira Leitão; Brasil, Thays Bezerra; Scochi, Carmen Gracinda Silvan

    2011-01-01

    This study investigated which physiological parameters change when endotracheal and upper airway suctioning is performed immediately before, immediately after and five minutes after this procedure is performed in newborns hospitalized in a Neonatal Intensive Care Unit (NICU). This is a quantitative and longitudinal study, before and after type, performed in the NICU of a public institution in the city of Fortaleza, CE, Brazil. The sample was composed of 104 newborns using oxigenotherapy and who needed endotracheal and upper airway suctioning. The results showed significant alterations in respiratory and heart rates (p<0.05) in neonates using Oxyhood and nasal CPAP while the pulse significantly changed (p<0.05) in newborns placed in oxyhood, using nasal CPAP and Mechanical Ventilation; oxygen saturation was the only parameter that did not alter significantly. We propose that nurses develop non-pharmacological interventions to reduce potential alterations caused in newborns' physiological parameters due to this procedure. PMID:22249671

  4. Approximation theory for boundary layer suction through individual slits

    NASA Technical Reports Server (NTRS)

    Walz, A.

    1979-01-01

    The basic concepts of influencing boundary layers are summarized, especially the prevention of flow detachment and the reduction of frictional resistance. A mathematical analysis of suction through a slit is presented with two parameters, for thickness and for shape of the boundary layer, being introduced to specify the flow's velocity profile behind the slit. An approximation of the shape parameter produces a useful formula, which can be used to determine the most favorable position of the slit. An aerodynamic example is given.

  5. Intermittent patient suction system, self-contained control

    DOEpatents

    Lewis, Jay L.

    1992-01-01

    An intermittent patient suction system, a self-contained control device therefor and methods of making the same are provided, the self-contained control device having a housing that contains two restrictor units therein for respectively controlling the "on" time and "off" time that the control device applies a vacuum and does not apply a vacuum through the output of the control device to the patient.

  6. Comparison the Effects of Shallow and Deep Endotracheal Tube Suctioning on Respiratory Rate, Arterial Blood Oxygen Saturation and Number of Suctioning in Patients Hospitalized in the Intensive Care Unit: A Randomized Controlled Trial

    PubMed Central

    Abbasinia, Mohammad; Irajpour, Alireza; Babaii, Atye; Shamali, Mehdi; Vahdatnezhad, Jahanbakhsh

    2014-01-01

    Introduction: Endotracheal tube suctioning is essential for improve oxygenation in the patients undergoing mechanical ventilation. There are two types of shallow and deep endotracheal tube suctioning. This study aimed to evaluate the effect of shallow and deep suctioning methods on respiratory rate (RR), arterial blood oxygen saturation (SpO2) and number of suctioning in patients hospitalized in the intensive care units of Al-Zahra Hospital, Isfahan, Iran. Methods: In this randomized controlled trial, 74 patients who hospitalized in the intensive care units of Isfahan Al-Zahra Hospital were randomly allocated to the shallow and deep suctioning groups. RR and SpO2 were measured immediately before, immediately after, 1 and 3 minute after each suctioning. Number of suctioning was also noted in each groups. Data were analyzed using repeated measures analysis of variance (RMANOVA), chi-square and independent t-tests. Results: RR was significantly increased and SpO2 was significantly decreased after each suctioning in the both groups. However, these changes were not significant between the two groups. The numbers of suctioning was significantly higher in the shallow suctioning group than in the deep suctioning group. Conclusion: Shallow and deep suctioning had a similar effect on RR and SpO2. However, shallow suctioning caused further manipulation of patient's trachea than deep suctioning method. Therefore, it seems that deep endotracheal tube suctioning method can be used to clean the airway with lesser manipulation of the trachea. PMID:25276759

  7. Numerical simulation of installation process and uplift resistance for an integrated suction foundation in deep ocean

    NASA Astrophysics Data System (ADS)

    Li, Ying; Yang, Shu-geng; Yu, Shu-ming

    2016-03-01

    A concept design, named integrated suction foundation, is proposed for a tension leg platform (TLP) in deep ocean. The most important improvement in comparing with the traditional one is that a pressure-resistant storage module is designed. It utilizes the high hydrostatic pressure in deep ocean to drive water into the module to generate negative pressure for bucket suction. This work aims to further approve the feasibility of the concept design in the aspect of penetration installation and the uplift force in-place. Seepage is generated during suction penetration, and can have both positive and negative effects on penetration process. To study the effect of seepage on the penetration process of the integrated suction foundation, finite element analysis (FEA) is carried out in this work. In particular, an improved methodology to calculate the penetration resistance is proposed for the integrated suction foundation with respect to the reduction factor of penetration resistance. The maximum allowable negative pressure during suction penetration is calculated with the critical hydraulic gradient method through FEA. The simulation results of the penetration process show that the integrated suction foundation can be installed safely. Moreover, the uplift resistance of the integrated suction foundation is calculated and the feasibility of the integrated suction foundation working on-site is verified. In all, the analysis in this work further approves the feasibility of the integrated suction foundation for TLPs in deep ocean applications.

  8. Proteolytic response to feeding level in rainbow trout (Oncorhynchus mykiss)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In fish there is a quadratic relationship between feed intake and feed efficiency, with optimal nutrient retention occurring at moderate levels of feed restriction. Determining how mechanisms controlling nutrient utilization are affected by feed intake, with a particular emphasis on those that impa...

  9. Fish oil supplementation suppresses resistance exercise and feeding-induced increases in anabolic signaling without affecting myofibrillar protein synthesis in young men.

    PubMed

    McGlory, Chris; Wardle, Sophie L; Macnaughton, Lindsay S; Witard, Oliver C; Scott, Fraser; Dick, James; Bell, J Gordon; Phillips, Stuart M; Galloway, Stuart D R; Hamilton, D Lee; Tipton, Kevin D

    2016-03-01

    Fish oil (FO) supplementation potentiates muscle protein synthesis (MPS) in response to a hyperaminoacidemic-hyperinsulinemic infusion. WhetherFOsupplementation potentiatesMPSin response to protein ingestion or when protein ingestion is combined with resistance exercise (RE) remains unknown. In a randomized, parallel group design, 20 healthy males were randomized to receive 5 g/day of eitherFOor coconut oil control (CO) for 8 weeks. After supplementation, participants performed a bout of unilateralREfollowed by ingestion of 30 g of whey protein. Skeletal muscle biopsies were obtained before and after supplementation for assessment of muscle lipid composition and relevant protein kinase activities. Infusion ofl-[ring-(13)C6] phenylalanine was used to measure basal myofibrillarMPSat rest (REST), in a nonexercised leg following protein ingestion (FED) and followingREand protein ingestion (FEDEX).MPSwas significantly elevated aboveRESTduringFEDEXin both theFOandCOgroups, but there was no effect of supplementation. There was a significant increase inMPSin both groups aboveRESTduringFEDbut no effect of supplementation. Supplementation significantly decreased panPKBactivity atRESTin theFOgroup but not theCOgroup. There was a significant increase fromRESTat post-REforPKBandAMPKα2 activity in theCOgroup but not in theFOgroup. InFEDEX, there was a significant increase in p70S6K1 activity fromRESTat 3 h in theCOgroup only. These data highlight that 8 weeks ofFOsupplementation alters kinase signaling activity in response toREplus protein ingestion without influencingMPS. PMID:27009278

  10. Fish Allergy

    MedlinePlus

    ... Story" 5 Things to Know About Zika & Pregnancy Fish Allergy KidsHealth > For Parents > Fish Allergy Print A ... From Home en español Alergia al pescado About Fish Allergy A fish allergy is not exactly the ...

  11. 46 CFR 134.180 - Piping for fire-main suction.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Piping for fire-main suction. 134.180 Section 134.180 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS ADDED PROVISIONS FOR LIFTBOATS § 134.180 Piping for fire-main suction. (a) Except as provided by paragraph (b) of this section, suction lines must comply with...

  12. AARC Clinical Practice Guidelines. Endotracheal suctioning of mechanically ventilated patients with artificial airways 2010.

    PubMed

    2010-06-01

    An electronic literature search for articles published between January 1990 and October 2009 was conducted by using MEDLINE, CINAHL, and Cochrane Library databases. The update of this clinical practice guideline is the result of reviewing a total of 114 clinical trials, 62 reviews and 6 meta-analyses on endotracheal suctioning. The following recommendations are made following the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria: (1) It is recommended that endotracheal suctioning should be performed only when secretions are present, and not routinely; (2) It is suggested that pre-oxygenation be considered if the patient has a clinically important reduction in oxygen saturation with suctioning; (3) Performing suctioning without disconnecting the patient from the ventilator is suggested; (4) Use of shallow suction is suggested instead of deep suction, based on evidence from infant and pediatric studies; (5) It is suggested that routine use of normal saline instillation prior to endotracheal suction should not be performed; (6) The use of closed suction is suggested for adults with high F(I)O2, or PEEP, or at risk for lung de-recruitment, and for neonates; (7) Endotracheal suctioning without disconnection (closed system) is suggested in neonates; (8) Avoidance of disconnection and use of lung recruitment maneuvers are suggested if suctioning-induced lung de-recruitment occurs in patients with ; (9) It is suggested that a suction catheter is used that occludes less than 50% the lumen of the endotracheal tube in children and adults, and less than 70% in infants; (10) It is suggested that the duration of the suctioning event be limited to less than 15 seconds. PMID:20507660

  13. One Fish Two Fish.

    ERIC Educational Resources Information Center

    Hoffman, Michele

    1998-01-01

    This activity explains fisheries resource management to seven-year olds. First-grade students learn concepts such as offspring viability, life expectancy, and distribution of species, which help to determine when, where, and how people fish and the importance of fishing responsibly. Lists materials, procedures, and extensions. (SJR)

  14. Gray whale and walrus feeding excavation on the Bering Shelf, Alaska.

    USGS Publications Warehouse

    Nelson, C.H.; Johnson, K.R.; Barber, J.H., Jr.

    1987-01-01

    The gray whales (average mouth length, 2.0 m), when suction feeding on infaunal amphipods, create shallow pits in the sea floor, typically 2.5m x 1.5m x 10cm deep, which are distinct and mappable on sidescan sonographs. Similarly, walrus, when foraging for shallow clams, create long, linear feeding furrows that average 47 x 0.4 x 0.1m (length-width-depth). The whale feeding pits are commonly enlarged and oriented by seasonal storm-related scour. Walrus-feeding features are smaller, formed in higher-energy environments, and modified more rapidly than whale-feeding pits. -from Authors

  15. Laminar free convection from a sphere with blowing and suction

    SciTech Connect

    Huang, Mingjer; Chen, Gahokuang )

    1987-05-01

    The effect of mass transfer on free convection from a vertical plate has been studied by Eichhorn (1960), Sparrow and Cess (1961), Merkin (1972), and Parikh (1974). Recently, Merkin (1975) gave an asymptotic series solution for two-dimensional bodies. Minkowycz and Sparrow (1979) studied a vertical cylinder in a natural convective flow. According to their conclusions, the heat transfer rate increases with suction and decreases with blowing. The present note is concerned with the study of the influence of Prandtl number and surface mass transfer on a steady, laminar, free convective flow over a sphere with nonuniform surface temperature or heat flux.

  16. Fat Harvest Using a Closed-Suction Drain

    PubMed Central

    Zakeri, Roxana; Mallucci, Patrick

    2016-01-01

    We propose a safe, simple, and novel method to harvest fat using a standard liposuction cannula and a Redivac or alternative closed-suction drain. The authors have used this technique for both 'dry' and 'wet' liposuction. This technique is both easy to perform and cost-effective whilst providing both a silent and relatively atraumatic fat harvest. The lower negative pressure compared with traditional harvesting systems likely preserves fat integrity for lipofilling. This method maximises resources already held within a hospital environment. PMID:27218029

  17. Fat Harvest Using a Closed-Suction Drain.

    PubMed

    Amin, Kavit; Zakeri, Roxana; Mallucci, Patrick

    2016-05-01

    We propose a safe, simple, and novel method to harvest fat using a standard liposuction cannula and a Redivac or alternative closed-suction drain. The authors have used this technique for both 'dry' and 'wet' liposuction. This technique is both easy to perform and cost-effective whilst providing both a silent and relatively atraumatic fat harvest. The lower negative pressure compared with traditional harvesting systems likely preserves fat integrity for lipofilling. This method maximises resources already held within a hospital environment. PMID:27218029

  18. Pump tank divider plate for sump suction sodium pumps

    DOEpatents

    George, John A.; Nixon, Donald R.

    1977-01-01

    A circular plate extends across the diameter of "sump suction" pump, with a close clearance between the edge of the plate and the wall of the pump tank. The plate is located above the pump impeller, inlet and outlet flow nozzles but below the sodium free surface and effectively divides the pump tank into two separate chambers. On change of pump speed, the close fitting flow restriction plate limits the rate of flow into or out of the upper chamber, thereby minimizing the rate of level change in the tank and permitting time for the pump cover gas pressure to be varied to maintain an essentially constant level.

  19. [Removal of bronchial foreign bodies by suction with a bronchoscope].

    PubMed

    Mita, Y; Dobashi, K; Saitoh, R; Tsuchiya, S; Nakano, H; Watanabe, S; Makimoto, T; Ishihara, S; Mori, M

    1997-04-01

    We report two cases in which intrabronchial foreign bodies were removed with a fiberoptic bronchoscope. In both cases the foreign body was a seed of a small Japanese apricot. Atelectasis or obstructive pneumonia was seen on chest roentgenograms. The foreign bodies were associated with slight inflammation and polyps on the bronchial epithelium. The foreign bodies were removed by applying suction with a fiberoptic bronchoscope. This method may also be useful for removing other large, hard, uneven, and ball-like foreign bodies. PMID:9212671

  20. Tree Water Uptake And Suction Distribution On Tropical Residual Soil Slope

    NASA Astrophysics Data System (ADS)

    Ishak, M. F.; Sulaiman, F. F.; Ali, N.; Kassim, A.

    2016-02-01

    This paper present an exploration of soil matric suction effected by water uptake via tree root at toe of slope on various condition between wet condition (high rainfall) and dry condition (prolonged no rainfall). Matric suction generated by active root tree has substantial influence soil moisture content on residual soil slope. A field monitoring was carried out to collect matric suction data at slope in two conditions; with a tree located at toe of slope and absent of a tree. The installations of instruments particularly at slope with tree at toe were placed within vicinity of the tree with certain depths and distances. The matric suction data from field monitoring was influence by the rainfall events that lead to the instability of soils slope. Analysis of soil matric suction distribution pattern indicates that the highest matric suction value was at shallower depth and proximity of tree. The matric suction profiles obtained from field monitoring are applied as an input data to develop soil matric suction contour. The effect of transpiration driven by active root zone generated matric suction on soil at vicinity of tree may create dry soil to increase soil shear strength.

  1. Endoscopic ultrasound-guided fine needle aspiration: The wet suction technique.

    PubMed

    Villa, Nicolas A; Berzosa, Manuel; Wallace, Michael B; Raijman, Isaac

    2016-01-01

    Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has become a fundamental tool in obtaining cytopathological diagnosis of pancreatic tumors. When sampling solid lesions of the pancreas, the endosonographer can use two suction techniques to enhance tissue acquisition; the dry and the wet suction techniques. The standard dry suction technique relies on applying negative pressure suction on the proximal end of the needle after the stylet is removed with a pre-vacuum syringe. The wet suction technique relies on pre-flushing the needle with saline to replace the column of air with fluid followed by aspiration the proximal end by using a prefilled syringe with saline. A new modified wet suction technique (hybrid suction technique) relies on preloading the needle with saline, but having continuous negative pressure with a pre-vacuum syringe to avoid manual intermittent suction. Tissue acquisition can be enhanced by applying fluid dynamic principles to the current aspiration techniques, such as the column of water used in the needle of the wet technique. In this review, we will focus on EUS-FNA using the wet suction technique for sampling of pancreatic solid lesions. PMID:26879162

  2. The NASA Langley laminar-flow-control experiment on a swept, supercritical airfoil: Suction coefficient analysis

    NASA Technical Reports Server (NTRS)

    Brooks, Cuyler W., Jr.; Harris, Charles D.; Harvey, William D.

    1991-01-01

    A swept supercritical wing incorporating laminar flow control at transonic flow conditions was designed and tested. The definition of an experimental suction coefficient and a derivation of the compressible and incompressible formulas for the computation of the coefficient from measurable quantities is presented. The suction flow coefficient in the highest velocity nozzles is shown to be overpredicted by as much as 12 percent through the use of an incompressible formula. However, the overprediction on the computed value of suction drag when some of the suction nozzles were operating in the compressible flow regime is evaluated and found to be at most 6 percent at design conditions.

  3. Endoscopic ultrasound-guided fine needle aspiration: The wet suction technique

    PubMed Central

    Villa, Nicolas A.; Berzosa, Manuel; Wallace, Michael B.; Raijman, Isaac

    2016-01-01

    Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has become a fundamental tool in obtaining cytopathological diagnosis of pancreatic tumors. When sampling solid lesions of the pancreas, the endosonographer can use two suction techniques to enhance tissue acquisition; the dry and the wet suction techniques. The standard dry suction technique relies on applying negative pressure suction on the proximal end of the needle after the stylet is removed with a pre-vacuum syringe. The wet suction technique relies on pre-flushing the needle with saline to replace the column of air with fluid followed by aspiration the proximal end by using a prefilled syringe with saline. A new modified wet suction technique (hybrid suction technique) relies on preloading the needle with saline, but having continuous negative pressure with a pre-vacuum syringe to avoid manual intermittent suction. Tissue acquisition can be enhanced by applying fluid dynamic principles to the current aspiration techniques, such as the column of water used in the needle of the wet technique. In this review, we will focus on EUS-FNA using the wet suction technique for sampling of pancreatic solid lesions. PMID:26879162

  4. Trematode infections in farm-raised fish: Reasons for massive infections, impacts on fish and fish farms, and management of infections on fish farms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is an increasing problem with trematodes in fish production facilities. The onset and growth of pond aquaculture in the US (1950-1990) resulted in concentrated areas of fish, new sites for snail growth and multiplication, and new bird feeding habitat. Snails, fish, and birds serve as hosts for...

  5. Effects of suction-dredging for cockles on non-target fauna in the Wadden Sea [rapid communication

    NASA Astrophysics Data System (ADS)

    Hiddink, J. G.

    2003-12-01

    Suction dredging for cockles removes large cockles from tidal flats and may also cause mortality of non-target fauna and make the habitat less suitable for some species. This study examines whether suction dredging for cockles on tidal flats of the Dutch Wadden Sea had affected densities of non-target fauna, directly after fishing and one year later. Densities of non-target fauna in two randomly chosen undredged locations were compared to densities at the surrounding heavily commercially dredged area. A significant negative effect of cockle dredging on densities of 0-group Macoma balthica was observed and this effect persisted one year after dredging. The dredged area appeared to be less suitable for settlement of mussels Mytilus edulis. No significant effects of dredging on the mudsnail Hydrobia ulvae and on 0 and 1-group C. edule were found. For the mobile young Macoma balthica it seems unlikely that the effect found after one year was still due to the mortality caused by dredging and this suggests that the habitat was less suitable as a consequence of dredging. Thus, even in the highly dynamic ecosystem of the Wadden Sea, effects of bottom disturbance by cockle dredging may persist after one year.

  6. Adaptive Suction and Blowing for Twin-Tail Buffet Control

    NASA Technical Reports Server (NTRS)

    Kandil, Osama A.; Yang, Zhi

    1999-01-01

    Adaptive active flow control for twin-tail buffet alleviation is investigated. The concept behind this technique is to place control ports on the tail outer and inner surfaces with flow suction or blowing applied through these ports in order to minimize the pressure difference across the tail. The suction or blowing volume flow rate from each port is proportional to the pressure difference across the tail at this location. A parametric study of the effects of the number and location of these ports on the buffet response is carried out. The computational model consists of a sharp-edged delta wing of aspect ratio one and swept-back flexible twin tail with taper ratio of 0.23. This complex multidisciplinary problem is solved sequentially using three sets of equations for the fluid flow, aeroelastic response and grid deformation, using a dynamic multi-block grid structure. The computational model is pitched at 30 deg angle of attack. The freestream Mach number and Reynolds number are 0.3 and 1.25 million, respectively. The model is investigated for the inboard position of the twin tails, which corresponds to a separation distance between the twin tails of 33% of the wing span. Comparison of the time history and power spectral density responses of the tails for various distributions of the control ports are presented and discussed.

  7. Assessment of capillary suction time (CST) test methodologies.

    PubMed

    Sawalha, O; Scholz, M

    2007-12-01

    The capillary suction time (CST) test is a commonly used method to measure the filterability and the easiness of removing moisture from slurry and sludge in numerous environmental and industrial applications. This study assessed several novel alterations of both the test methodology and the current standard capillary suction time (CST) apparatus. Twelve different papers including the standard Whatman No. 17 chromatographic paper were tested. The tests were run using four different types of sludge including a synthetic sludge, which was specifically developed for benchmarking purposes. The standard apparatus was altered by the introduction of a novel rectangular funnel instead of a standard circular one. A stirrer was also introduced to solve the problem of test inconsistency (e.g. high CST variability) particularly for heavy types of sludge. Results showed that several alternative papers, which are cheaper than the standard paper, can be used to estimate CST values accurately, and that the test repeatability can be improved in many cases and for different types of sludge. The introduction of the rectangular funnel demonstrated an obvious enhancement of test repeatability. The use of a stirrer to avoid sedimentation of heavy sludge did not have statistically significant impact on the CST values or the corresponding data variability. The application of synthetic sludge can support the testing of experimental methodologies and should be used for subsequent benchmarking purposes. PMID:18341148

  8. Successful closed suction drain management of a canine elbow hygroma.

    PubMed

    Pavletic, M M; Brum, D E

    2015-07-01

    A 1-year-old castrated male St. Bernard dog presented to Angell Animal Medical Center with bilateral elbow hygromas which had been present for several weeks. The largest hygroma involving the left elbow was managed with a closed suction (active) drain system to continuously collapse the hygroma pocket over a 3-week period. Soft bedding was used to protect the elbows from further impact trauma to the olecranon areas. Following drain removal, there was no evidence of hygroma recurrence based on periodic examinations over an 18-month period. The smaller non-operated right elbow hygroma had slightly enlarged during this period. Closed suction drain management of the hygroma proved to be a simple and economical method of collapsing the left elbow hygroma. This closed drainage system eliminated the need for the postoperative bandage care required with the use of the Penrose (passive) drain method of managing elbow hygromas. The external drain tube should be adequately secured in order to minimise the risk of its inadvertent displacement. PMID:25640711

  9. [Swimming pool suction injury: etiology, profylaxis and management].

    PubMed

    Škach, J; Kašák, P; Šrám, J

    2015-01-01

    Swimming pool suction injuries are unique and rare with a substantive risk of fatal consequences. Little children under the age of 8 are the most frequent victims with serious injuries. Drownings of different seriousness are also a usual part of accidents. The case of a 19 year old man trapped in the gluteal area by a unsecured suction drainage hole illustrates the uniqueness of this problem in an interesting way. Prophylactic arrangements are well known but the problem is with their strict application. Fatal causes excluding drowning include hypovolemic shock from the sudden redistribution of intersticial fluid and blood and also the evisceration of the bowel and other abdominal organs. Localised often bizarre and large swellings and sufusions can be treated nonoperatively in the vast majority of cases. For the prevention of these injuries it is important to inform the public and increase their awareness to these injuries. It is also crucial for the correct management of these injuries a deeper awareness of this issue and a sharing of experiences and solutions with other experts.Key words: vacuum - accident - entrapment - compartment syndrome. PMID:25604983

  10. Temperature measurement in WTE boilers using suction pyrometers.

    PubMed

    Rinaldi, Fabio; Najafi, Behzad

    2013-01-01

    The temperature of the flue-gas in the post combustion zone of a waste to energy (WTE) plant has to be maintained within a fairly narrow range of values, the minimum of which is prescribed by the European Waste Directive 2000/76/CE, whereas the maximum value must be such as to ensure the preservation of the materials and the energy efficiency of the plant. A high degree of accuracy in measuring and controlling the aforementioned temperature is therefore required. In almost the totality of WTE plants this measurement process is carried out by using practical industrial thermometers, such as bare thermocouples and infrared radiation (IR) pyrometers, even if affected by different physical contributions which can make the gas temperature measurements incorrect. The objective of this paper is to analyze errors and uncertainties that can arise when using a bare thermocouple or an IR pyrometer in a WTE plant and to provide a method for the in situ calibration of these industrial sensors through the use of suction pyrometers. The paper describes principle of operation, design, and uncertainty contributions of suction pyrometers, it also provides the best estimation of the flue-gas temperature in the post combustion zone of a WTE plant and the estimation of its expanded uncertainty. PMID:24248279

  11. Behavior of Water Jet Accompanied with Air Suction

    NASA Astrophysics Data System (ADS)

    Kawakami, Hironobu; Ishido, Tsutomu; Ihara, Akio

    In order to atomize a liquid, the authors have investigated the behavior of air-water jets. In a series of experiments, we have discovered a strange phenomenon that the water jet accompanied with air suction from the free surface has made a periodic radial splash of water drop. The purpose of the present paper is to clear out the origin of this phenomenon and the behavior of water jet accompanied with air suction. The behavior of water jet has been photographed by a digital camera aided with a flashlight and high-speed video camera. Those experiments enable us to find the origin of a periodic radial splash due to a formation of single air bubble at the flow separation region inside the nozzle and due to explosive expansion of the bubble after injected in the free space. In order to analyze the radial splash of water, we have conducted the equation of spherical liquid membrane. The numerical results obtained have been compared with the experimental results and good agreement has been obtained in radial expansion velocity.

  12. Cavitation improvement of double suction centrifugal pump HPP Fuhren

    NASA Astrophysics Data System (ADS)

    Škerlavaj, A.; Titzschkau, M.; Pavlin, R.; Vehar, F.; Mežnar, P.; Lipej, A.

    2012-11-01

    A double suction storage pump has been refurbished because of the strong cavitation which resulted in cavitation damage on blade and consequently in frequent repairs of the impeller. The analyses of the old and the new impeller were done by the computational fluid dynamics (CFD), performing transient simulations with the commercial solver Ansys CFX. In the simulations, the scale-adaptive-simulation with the curvature correction (SAS-CC) turbulence model was used. No model tests were carried out. Additionally, observations with the digital camera were made through the specially designed plexi-glass window, mounted at the lid at the suction side. The predicted pump head at the operating point agrees well with the pump characteristics measurements, performed with the direct thermodynamic method. The extent of the cavitation predicted by CFD is smaller than the observed one because the cloud cavitation was not predicted. The observations of the cavitation extent show that the impeller design is better than the old one, which was also possible to anticipate based on the CFD results.

  13. An Ultrasonic Suction Pump with No Physically Moving Parts

    NASA Astrophysics Data System (ADS)

    Yun, Cheol-Ho; Hasegawa, Takeshi; Nakamura, Kentaro; Ueha, Sadayuki

    2004-05-01

    A new ultrasonic suction pump is described in this paper. The pump uses the suction force of a rigid cylinder tube vibrating at an ultrasonic frequency and has no physically moving parts. The pump consists of a longitudinal bolt-clamped Langevin transducer (BLT) combined with a stepped horn working at a resonance frequency of 24 kHz. A glass tube with the length of the half-wavelength-resonance is glued at the tip of the horn. To enhance pump performance, we introduced a reflection plate and a thin rod installed to the end of the glass tube with a small gap. Maximum pressures of 7.2 kPa and 23.5 kPa were recorded using the reflection plate and the thin rod, respectively. In this study, we experimentally investigate the characteristics of the pump and the operating physics. The maximum pressure is a function of the vibration velocity of the end surface of the glass tube and of the gap.

  14. Temperature Measurement in WTE Boilers Using Suction Pyrometers

    PubMed Central

    Rinaldi, Fabio; Najafi, Behzad

    2013-01-01

    The temperature of the flue-gas in the post combustion zone of a waste to energy (WTE) plant has to be maintained within a fairly narrow range of values, the minimum of which is prescribed by the European Waste Directive 2000/76/CE, whereas the maximum value must be such as to ensure the preservation of the materials and the energy efficiency of the plant. A high degree of accuracy in measuring and controlling the aforementioned temperature is therefore required. In almost the totality of WTE plants this measurement process is carried out by using practical industrial thermometers, such as bare thermocouples and infrared radiation (IR) pyrometers, even if affected by different physical contributions which can make the gas temperature measurements incorrect. The objective of this paper is to analyze errors and uncertainties that can arise when using a bare thermocouple or an IR pyrometer in a WTE plant and to provide a method for the in situ calibration of these industrial sensors through the use of suction pyrometers. The paper describes principle of operation, design, and uncertainty contributions of suction pyrometers, it also provides the best estimation of the flue-gas temperature in the post combustion zone of a WTE plant and the estimation of its expanded uncertainty. PMID:24248279

  15. Unique solar flare of September 22, 2011: The suction effect

    NASA Astrophysics Data System (ADS)

    Solov'ev, A. A.; Kirichek, E. A.; Ganiev, V. V.

    2013-12-01

    The specific features in the development of an X1 solar flare, which occurred on September 22, 2011, and was registered with the Atmospheric Imaging Assembly (AIA) device onboard the Solar Dynamics Observatory (SDO) in the UV line (λ = 304 Å, He II), are analyzed. During the flare, which lasted about 12 h, cold plasma was sucked up with an increasing velocity from a very distant region into the low-lying hot region of flare energy release along a flat helical trajectory. This phenomenon fundamentally differs from a surge ejection, when matter previously ejected from the flare region returns to the flare hot zone under the action of gravity. Suction of cold plasma "from outside" into the hot flare region is interpreted in the scope of the rope flare mechanism, according to which an extremely inhomogeneous plasma density distribution in the cross-section originates in an emerging magnetic rope. In the region with a sharply decreased density (which is the suction region), the drift velocity in the current chanel can reach the ion thermal velocity, which inevitably results in the excitation of plasma turbulence and anomalous resistance, i.e., in the development of a flare.

  16. The better to eat you with: the comparative feeding morphology of phocid seals (Pinnipedia, Phocidae).

    PubMed

    Kienle, Sarah S; Berta, Annalisa

    2016-03-01

    One adaptation crucial to the survival of mammalian lineages that secondarily transitioned from land to water environments was the ability to capture and consume prey underwater. Phocid seals have evolved diverse feeding strategies to feed in the marine environment, and the objectives of this study were to document the specialized feeding morphologies and identify feeding strategies used by extant phocids. This study used principal component analysis (PCA) to determine the major axes of diversification in the skull for all extant phocid taxa and the recently extinct Caribbean monk seal (n = 19). Prey data gathered from the literature and musculoskeletal data from dissections were included to provide a comprehensive description of each feeding strategy. Random Forest analysis was used to determine the morphological, ecological and phylogenetic variables that best described each feeding strategy. There is morphological evidence for four feeding strategies in phocids: filter; grip and tear; suction; and pierce feeding. These feeding strategies are supported by quantitative cranial and mandibular characters, dietary information, musculoskeletal data and, for some species, behavioral observations. Most phocid species are pierce feeders, using a combination of biting and suction to opportunistically catch prey. Grip and tear and filter feeding are specialized strategies with specific morphological adaptations. These unique adaptations have allowed leopard seals (Hydrurga leptonyx) and crabeater seals (Lobodon carcinophaga) to exploit novel ecological niches and prey types. This study provides the first cranial and mandibular morphological evidence for the use of specialized suction feeding in hooded seals (Cystophora cristata), northern elephant seals (Mirounga angustirostris) and southern elephant seals (Mirounga leonina). The most important variables in determining the feeding strategy of a given phocid species were cranial and mandibular shape, diet, and phylogeny

  17. Feed training of peacock bass (Cichla sp.).

    PubMed

    Moura, M A; Kubitza, F; Cyrino, J E

    2000-11-01

    The Amazonian cichlid peacock bass (Cichla sp.) is a highly marketable food and sport fish, therefore a suitable species for aquaculture. However, because of its piscivorous feeding preferences, the species does not accept dry feeds voluntarily, turning its intensive culture difficult and costly. This study aimed to wean fingerling peacock bass from inert moist food to dry diets. In a first experiment, 1,134 fingerlings weighting 0.27 g were divided in two 0.37 m3 hapas and fed ground fish flesh with 35% success. Then, 1.3 g fish were pooled, stocked in six 25 L cages and fed two pellet sequences with 80%, 60%, 40%, 20% and 0% ground fish flesh (GFF). One sequence was flavored with 10% krill meal (Euphausia sp.). Training success of fish fed the GFF-00 diet flavored with krill reached 12%a compared to 11.6%a (p < 0.05) for diets without krill meal. A second experiment was set up with 969, 1.5 g fish, trained with GFF with 39.8% success. After the feed training period, 2.2 g fish were then fed a sequence of moist pellets containing 80%, 60% and 45% GFF. Fish trained to feed on moist pellets with 45% ground fish were pooled and stocked into nine 25 L cages. Fish were weaned to dry pellets without ground fish flesh (GFF-00) using three diet sequences: 1) dry pellets; 2) moist pellets; and 3) dry pellets flavored with 4% cod liver oil; all three diets contained 30, 10 and 0% GFF. The three sequences yielded, respectively 30.8%a, 23.6%a, and 24.7%a (p < 0.05) fish feeding on GFF-00. There were no apparent beneficial effects of increasing moisture or addition of cod liver oil as flavor enhancers in the weaning diets. This study revealed the feasibility of training peacock bass to accept dry pellets, but feeding young fish ground fish flesh seemed to be a major bottleneck in improving feed training success. PMID:11241964

  18. Repeated open endotracheal suctioning causes gradual desaturation but does not exacerbate lung injury compared to closed endotracheal suctioning in a rabbit model of ARDS

    PubMed Central

    2013-01-01

    Background Although endotracheal suctioning induces alveolar derecruitment during mechanical ventilation, it is not clear whether repeated endotracheal suctioning exacerbates lung injuries. The present study aimed to determine whether repeated open endotracheal suctioning (OS) exacerbates lung injury compared to closed endotracheal suctioning (CS) during mechanical ventilation in an animal model of acute respiratory distress syndrome (ARDS). Methods Briefly, thirty six Japanese white rabbits were initially ventilated in pressure-controlled mode with a constant tidal volume (6 mL/kg). Then, lung injury was induced by repeated saline lavage. The rabbits were divided into four groups, namely: a) OS; b) CS; c) control with ARDS only; d) and healthy control (HC) without ARDS. Animals in all the groups were then ventilated with positive end expiratory pressure (PEEP) at 10 cm H2O. CS was performed using 6 French-closed suctioning catheters connected to endotracheal tube under the following conditions: a) a suctioning time and pressure of 10 sec and 140 mm Hg, respectively; and b) a suction depth of 2 cm (length of adapter) plus tracheal tube. OS was performed using the same conditions described for CS, except the ventilator was disconnected from the animals. Each endotracheal suctioning was performed at an interval of 30 min. Results PaO2/FIO2 (P/F) ratio for CS, control and HC groups remained at >400 for 6 hours, whereas that of the OS group progressively declined to 300 (p < 0.05), with each suctioning. However, no difference was observed either in lung injury score (histology) or in the expression pattern of inflammatory cytokines (tumor necrosis factor-α and interleukin-6) after 6 hours between the OS and CS groups in the circulatory as well as the pulmonary tissues. Conclusions Progressive arterial desaturation under conditions of repeated endotracheal suctioning is greater in OS than in CS time-dependently. However, OS does not exacerbate lung injury

  19. Development of advanced stability theory suction prediction techniques for laminar flow control. [on swept wings

    NASA Technical Reports Server (NTRS)

    Srokowski, A. J.

    1978-01-01

    The problem of obtaining accurate estimates of suction requirements on swept laminar flow control wings was discussed. A fast accurate computer code developed to predict suction requirements by integrating disturbance amplification rates was described. Assumptions and approximations used in the present computer code are examined in light of flow conditions on the swept wing which may limit their validity.

  20. Real-time imaging of suction blistering in human skin using optical coherence tomography.

    PubMed

    Carvalho, Joana C O; Palero, Jonathan A; Jurna, Martin

    2015-12-01

    Separation of skin epidermis from the dermis by suction blistering has been used with high success rate for autologous skin epidermal grafting in burns, chronic wounds and vitiligo transplantation treatment. Although commercial products that achieve epidermal grafting by suction blistering are presently available, there is still limited knowledge and understanding on the dynamic process of epidermal-dermal separation during suction blistering. In this report we integrated a suction system to an Optical Coherence Tomography (OCT) which allowed for the first time, real-time imaging of the suction blistering process in human skin. We describe in this report the evolution of a suction blister where the growth is modeled with a Boltzmann sigmoid function. We further investigated the relationship between onset and steady-state blister times, blister growth rate, applied suction pressure and applied local skin temperature. Our results show that while the blister time is inversely proportional to the applied suction pressure, the relationship between the blister time and the applied temperature is described by an exponential decay. PMID:26713194

  1. 21 CFR 870.4270 - Cardiopulmonary bypass cardiotomy suction line blood filter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... blood filter. 870.4270 Section 870.4270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Devices § 870.4270 Cardiopulmonary bypass cardiotomy suction line blood filter. (a) Identification. A cardiopulmonary bypass cardiotomy suction line blood filter is a device used as part of a gas exchange...

  2. 21 CFR 870.4270 - Cardiopulmonary bypass cardiotomy suction line blood filter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... blood filter. 870.4270 Section 870.4270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Devices § 870.4270 Cardiopulmonary bypass cardiotomy suction line blood filter. (a) Identification. A cardiopulmonary bypass cardiotomy suction line blood filter is a device used as part of a gas exchange...

  3. 21 CFR 870.4270 - Cardiopulmonary bypass cardiotomy suction line blood filter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... blood filter. 870.4270 Section 870.4270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Devices § 870.4270 Cardiopulmonary bypass cardiotomy suction line blood filter. (a) Identification. A cardiopulmonary bypass cardiotomy suction line blood filter is a device used as part of a gas exchange...

  4. 21 CFR 870.4270 - Cardiopulmonary bypass cardiotomy suction line blood filter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... blood filter. 870.4270 Section 870.4270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Devices § 870.4270 Cardiopulmonary bypass cardiotomy suction line blood filter. (a) Identification. A cardiopulmonary bypass cardiotomy suction line blood filter is a device used as part of a gas exchange...

  5. 21 CFR 870.4270 - Cardiopulmonary bypass cardiotomy suction line blood filter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... blood filter. 870.4270 Section 870.4270 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Devices § 870.4270 Cardiopulmonary bypass cardiotomy suction line blood filter. (a) Identification. A cardiopulmonary bypass cardiotomy suction line blood filter is a device used as part of a gas exchange...

  6. An Analysis of Reciprocating Compressor Suction System Using Digital Image Processing

    NASA Astrophysics Data System (ADS)

    Lee, In-Seop; Kaga, Akikazu; Yamaguchi, Katsuhito

    In a reciprocating compressor having close distance between a suction pipe and a suction muffler, great part of refrigerant flowing from the suction pipe is directly sucked into the suction muffler. But a part of refrigerant leaks into the void space in the hermetic shell and contacts with the cylinder, the motor or other high temperature parts. The temperature rise of refrigerant due to this leakage decreases the efficiency of a compressor. Therefore the efficiency of the compressor increases with decrease the amount of leakage. In this paper, the direct suction ratio (DSR) is defined as the ratio of the flow rate of refrigerant directly sucked to the total flow rate from the suction pipe, and measured with a new technique using digital image processing. The technique developed measures the temporal decrease of visible tracer particles filled initially within the hermetic shell of a compressor visualization model, and calculates the DSR from the rate of concentration decrease. The technique is applied to improve the performance of reciprocating compressor by modifying the shape of the suction pipe which gives higher DSR. Although refrigerant flow velocity around suction pipe and muffler is required as a fundamental data for further improvement of the performance, there has been no report or paper which measures these data due to the difficulty in insertion of velocity sensor into hermetic shell. In this paper, flow velocity data obtained with a PIV (Particle Imaging Velocimetry) technique applied to compressor visualization model is also presented.

  7. 46 CFR 134.180 - Piping for fire-main suction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Piping for fire-main suction. 134.180 Section 134.180 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS ADDED PROVISIONS FOR LIFTBOATS § 134.180 Piping for fire-main suction. (a) Except as provided by paragraph (b) of...

  8. 46 CFR 134.180 - Piping for fire-main suction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Piping for fire-main suction. 134.180 Section 134.180 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS ADDED PROVISIONS FOR LIFTBOATS § 134.180 Piping for fire-main suction. (a) Except as provided by paragraph (b) of...

  9. 46 CFR 134.180 - Piping for fire-main suction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Piping for fire-main suction. 134.180 Section 134.180 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS ADDED PROVISIONS FOR LIFTBOATS § 134.180 Piping for fire-main suction. (a) Except as provided by paragraph (b) of...

  10. 46 CFR 134.180 - Piping for fire-main suction.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Piping for fire-main suction. 134.180 Section 134.180 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS ADDED PROVISIONS FOR LIFTBOATS § 134.180 Piping for fire-main suction. (a) Except as provided by paragraph (b) of...

  11. DETAIL OF DENVER DISC FILTER IN CO91107, SUCTION END. NOTE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF DENVER DISC FILTER IN CO-91-107, SUCTION END. NOTE BEARING HOUSING WITH CAST LOGO, SUCTION PIPE GOING OFF TO THE RIGHT, AND FILTER DISC IN BACKGROUND. VACUUM INSIDE DISCS FURTHER DEWATERED CONCENTRATE. AS DISC SLOWLY ROTATED A BAR SCRAPED DRIED CONCENTRATE FROM OUTSIDE OF FILTER CLOTH. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  12. Real-time imaging of suction blistering in human skin using optical coherence tomography

    PubMed Central

    Carvalho, Joana C.O.; Palero, Jonathan A.; Jurna, Martin

    2015-01-01

    Separation of skin epidermis from the dermis by suction blistering has been used with high success rate for autologous skin epidermal grafting in burns, chronic wounds and vitiligo transplantation treatment. Although commercial products that achieve epidermal grafting by suction blistering are presently available, there is still limited knowledge and understanding on the dynamic process of epidermal-dermal separation during suction blistering. In this report we integrated a suction system to an Optical Coherence Tomography (OCT) which allowed for the first time, real-time imaging of the suction blistering process in human skin. We describe in this report the evolution of a suction blister where the growth is modeled with a Boltzmann sigmoid function. We further investigated the relationship between onset and steady-state blister times, blister growth rate, applied suction pressure and applied local skin temperature. Our results show that while the blister time is inversely proportional to the applied suction pressure, the relationship between the blister time and the applied temperature is described by an exponential decay. PMID:26713194

  13. Determination of sulfadiazine, trimethoprim, and N(4) -acetyl-sulfadiazine in fish muscle plus skin by Liquid Chromatography-Mass Spectrometry. Withdrawal-time calculation after in-feed administration in gilthead sea bream (Sparus aurata L.) fed two different diets.

    PubMed

    Zonaras, V; Tyrpenou, A; Alexis, M; Koupparis, M

    2016-10-01

    This study presents a depletion study for sulfadiazine and trimethoprim in muscle plus skin of gilthead sea bream (Sparus aurata L.). N(4) -acetyl-sulfadiazine, the main metabolite of sulfadiazine (SDZ), was also examined. The fish were held in seawater at a temperature of 24-26 °C. SDZ and trimethoprim (TMP) were administered orally with medicated feed for five consecutive days at daily doses of 25 mg SDZ and 5 mg TMP per kg of fish body weight per day. Two different diets, fish oil- and plant oil-based diets, were investigated. Ten fish were sampled at each of the days 1, 3, 5, 6, 8, 9, 10, and 12 after the start of veterinary medicine administration. However for the calculation of the withdrawal periods, sampling day 1 was set as 24 h after the last dose of the treatment. Fish samples were analyzed for SDZ, TMP, and acetyl-sulfadiazine (AcSDZ) residues by liquid chromatography-mass spectrometry. SDZ and TMP concentrations declined rapidly from muscle plus skin. Considering a maximum residue limit of 100 μg/kg for the total of sulfonamides and 50 μg/kg for TMP residues in fish muscle plus skin, the withdrawal periods of the premix trimethoprim-sulfadiazine 50% were calculated as 5 and 6 days, at 24-26 °C, in fish oil (FO) and plant oil (PO) groups, respectively. The investigation of this work is important to protect consumers by controlling the undesirable residues in fish. PMID:26987772

  14. Experiments on the stability of the flat-plate boundary layer with suction

    NASA Technical Reports Server (NTRS)

    Reynolds, G. A.; Saric, W. S.

    1982-01-01

    Experiments have been conducted in the VPI and SU Stability Wind Tunnel on a flat-plate wind-tunnel model equipped with porous suction panels. Detailed hot-wire measurements were conducted in the laminar boundary layer to investigate the stabilizing effects of suction on growing Tollmien-Schlichting waves, which were introduced into the boundary layer using a vibrating ribbon. Special care was taken to minimize external disturbances and to avoid extraneous experimental bias. The measurements, which included mean-flow and disturbance-amplitude profiles across the boundary layer, showed that suction applied through discrete porous strips can be as effective as suction applied continuously over a much longer streamwise length. The measurements also showed that suction is more effective when placed forward, nearer to the region of neutral stability, than when placed in the region of maximum growth rate. These results also provided meaningful comparison with recent theory.

  15. Fish Hearing.

    ERIC Educational Resources Information Center

    Blaxter, J. H. S.

    1980-01-01

    Provides related information about hearing in fish, including the sensory stimulus of sound in the underwater environment, mechanoreceptors in fish, pressure perception and the swimbladder, specializations in sound conduction peculiar to certain fish families. Includes numerous figures. (CS)

  16. City Fishing.

    ERIC Educational Resources Information Center

    Lange, Robert E.

    1979-01-01

    A program of supplying opportunities for fishing at locations within and near urban areas was developed. This effort included stocking, management of bodies of water for fishing, and presentation of fishing clinics for urban fishermen. (RE)

  17. 7 CFR 1437.303 - Aquaculture, including ornamental fish.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Aquaculture, including ornamental fish. 1437.303... ASSISTANCE PROGRAM Determining Coverage Using Value § 1437.303 Aquaculture, including ornamental fish. (a... human consumption as determined by CCC. (2) Fish raised as feed for other fish that are consumed...

  18. 7 CFR 1437.303 - Aquaculture, including ornamental fish.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Aquaculture, including ornamental fish. 1437.303... ASSISTANCE PROGRAM Determining Coverage Using Value § 1437.303 Aquaculture, including ornamental fish. (a... human consumption as determined by CCC. (2) Fish raised as feed for other fish that are consumed...

  19. 7 CFR 1437.303 - Aquaculture, including ornamental fish.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Aquaculture, including ornamental fish. 1437.303... ASSISTANCE PROGRAM Determining Coverage Using Value § 1437.303 Aquaculture, including ornamental fish. (a... human consumption as determined by CCC. (2) Fish raised as feed for other fish that are consumed...

  20. 7 CFR 1437.303 - Aquaculture, including ornamental fish.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Aquaculture, including ornamental fish. 1437.303... ASSISTANCE PROGRAM Determining Coverage Using Value § 1437.303 Aquaculture, including ornamental fish. (a... human consumption as determined by CCC. (2) Fish raised as feed for other fish that are consumed...

  1. Feeding Tubes

    MedlinePlus

    ... administer the TPN. Tubes Used for Enteral Feeds NG (Nasogastric Tube) A flexible tube is placed via ... down through the esophagus into the stomach. The NG tube can be used to empty the stomach ...

  2. Report on 5641 outpatient abortions by vacuum suction curettage

    PubMed Central

    Morgentaler, Henry

    1973-01-01

    A technique of ambulatory abortion for first trimester pregnancies by vacuum suction curettage under local anesthesia with intracervical block is described. The apparatus and relevant problems are discussed. A shortened speculum devised by the author and considered an improvement for this procedure, and a simplified sterile field are described. The complication rate of 0.48% based on 5641 reported cases is very low: there were no deaths, two cases of uterine perforation, 14 of incomplete abortion, 20 of infection, 1 of depression, no cervical lacerations; 27 patients were hospitalized. The advantages of this method are safety, simplicity, minimal blood loss and immediate recovery. It is preferable to the usual dilatation and curettage, does not require general anesthesia and can be used in small clinics or in hospitals on an ambulatory basis. PMID:4758593

  3. Flat slab deformation caused by interplate suction force

    NASA Astrophysics Data System (ADS)

    Ma, Yiran; Clayton, Robert W.

    2015-09-01

    We image the structure at the southern end of the Peruvian flat subduction zone, using receiver function and surface wave methods. The Nazca slab subducts to ~100 km depth and then remains flat for ~300 km distance before it resumes the dipping subduction. The flat slab closely follows the topography of the continental Moho above, indicating a strong suction force between the slab and the overriding plate. A high-velocity mantle wedge exists above the initial half of the flat slab, and the velocity resumes to normal values before the slab steepens again, indicating the resumption of dehydration and ecologitization. Two prominent midcrust structures are revealed in the 70 km thick crust under the Central Andes: molten rocks beneath the Western Cordillera and the underthrusting Brazilian Shield beneath the Eastern Cordillera.

  4. Localized travelling waves in the asymptotic suction boundary layer

    NASA Astrophysics Data System (ADS)

    Kreilos, Tobias; Gibson, John F.; Schneider, Tobias M.

    2016-05-01

    We present two spanwise-localized travelling wave solutions in the asymptotic suction boundary layer, obtained by continuation of solutions of plane Couette flow. One of the solutions has the vortical structures located close to the wall, similar to spanwise-localized edge states previously found for this system. The vortical structures of the second solution are located in the free stream far above the laminar boundary layer and are supported by a secondary shear gradient that is created by a large-scale low-speed streak. The dynamically relevant eigenmodes of this solution are concentrated in the free stream, and the departure into turbulence from this solution evolves in the free stream towards the walls. For invariant solutions in free-stream turbulence, this solution thus shows that that the source of energy of the vortical structures can be a dynamical structure of the solution itself, instead of the laminar boundary layer.

  5. Case study involving suctioning of an electromyographic endotracheal tube.

    PubMed

    Evanina, Eileen Youshock; Hanisak, Jill L

    2005-04-01

    The electromyographic endotracheal tube (EMG-ETT) is a relatively new tool used to measure integrity of the vocal cord structures during surgery. We describe a case in which an EMG-ETT was inserted for the operative period but not replaced with an ETT during the immediate postoperative period. Intensive care unit nurses had difficulty suctioning the EMG-ETT. The patient was not provided the pulmonary toilet necessary until the EMG-ETT was removed and replaced with a regular ETT. The purpose of this article is to make anesthesia providers aware that when mechanical ventilation is required during the postoperative period, the EMG-ETT should be removed and replaced with a regular ETT to facilitate pulmonary toilet. PMID:15835830

  6. Effects of shallow and deep endotracheal tube suctioning on cardiovascular indices in patients in intensive care units

    PubMed Central

    Irajpour, Alireza; Abbasinia, Mohammad; Hoseini, Abbas; Kashefi, Parviz

    2014-01-01

    Background: Clearing the endotracheal tube through suctioning should be done to promote oxygenation. Depth of suctioning is one of the variables in this regard. In shallow suctioning method, the catheter passes to the tip of the endotracheal tube, and in deep suctioning method, it passes beyond the tip into the trachea or brunches. This study aimed to evaluate the effect of shallow and deep suctioning methods on cardiovascular indices in patients hospitalized in the intensive care units (ICUs). Materials and Methods: In this clinical trial, 74 patients were selected among those who had undergone mechanical ventilation in the ICU of Al-Zahra Hospital, Isfahan, Iran using convenience sampling method. The subjects were randomly allocated to shallow and deep suctioning groups. Heart rate (HR) and blood pressure (BP) were measured immediately before and 1, 2, and 3 min after each suctioning. Number of times of suctioning was also noted in both the groups. Data were analyzed using repeated measures analysis of variance (ANOVA), Chi-square and independent t-tests. Results: HR and BP were significantly increased after suctioning in both the groups (P < 0.05). But these changes were not significant between the two groups (P > 0.05). The suctioning count was significantly higher in the shallow suctioning group than in the deep suctioning group. Conclusions: Shallow and deep suctioning were similar in their effects on HR and BP, but shallow suctioning caused further manipulation of patient's trachea than deep suctioning method. Therefore, in order to prevent complications, nurses are recommended to perform the endotracheal tube suctioning by the deep method. PMID:25183976

  7. Uniform flow over a permeable plane with downward suction

    NASA Astrophysics Data System (ADS)

    Hsieh, Ping-Cheng; Lin, Yen-Ti

    2015-04-01

    In previous research, studies on channel flow were mostly focused on the flow profiles with consideration of the horizontal (or streamwise) velocity component only. Due to the neglect of the vertical velocity component, the governing equations were simplified and then the analytical solutions could be probably derived. However, the vertical velocity as well as the horizontal velocity is actually existent in the real world, especially at the water-porous matrix interface. This study derives an analytical solution to a two-dimensional flow field composed of a uniform flow over a plane homogeneous porous medium with downward suction. The Navier-Stokes equations are employed to describe the water flow, whereas the poroelastic theory is addressed for the pore water flow. Setting the stream function for the velocity components associated with corresponding boundary conditions, we successfully find the solutions to the dimensionless boundary-value problem by taking the six-order power series method (PSM) and differential transform method (DTM), respectively. After the stream function is solved, the vertical velocity component as well as the horizontal velocity component can be obtained. The present results agree very well with the previous study which was carried out by a numerical method. This validates the presented analytical solutions separately by PSM and DTM. The vertical velocity increases gradually from the top lid to the bottom of the porous medium. The maximum horizontal velocity component is about 1.64 times of the downward suction velocity and occurs at a little below the centerline of the total depth. It is noted that the vertical velocity component should not be neglected in a two-dimensional flow, and the horizontal velocity might be affected by the vertical one. The present study also shows that the flow field of a two-dimensional flow is possible to be solved by analytical approaches. The employed technique and methods will be applied to the future study

  8. Feed Fish Effluent and Reel in Savings

    ERIC Educational Resources Information Center

    Wert, Frank S.; Henderson, Upton B.

    1978-01-01

    Discusses the ways in which aquaculture can be a cost-effective wastewater treatment alternative. Fifteen strategies were selected as being appropriate and technologically feasible wastewater treatment systems to compare for the size of community under consideration. Costs for each stage of each strategy were estimated and compared. (Author/MA)

  9. Managing urine leakage following laparoscopic radical prostatectomy with active suction of the prevesical space

    PubMed Central

    Stránský, Petr; Klečka, Jiří; Trávníček, Ivan; Ürge, Tomáš; Eret, Viktor; Ferda, Jiří; Petersson, Fredrik; Hes, Ondřej

    2012-01-01

    Introduction Urine leakage following laparoscopic radical prostatectomy (LRP) is a possible complication that may herald chronic urine incontinence. Intraoperative measures aiming to prevent this is not standardised. Aim Presentation of experience with active suction of the prevesical space in managing postoperative urine leakage. Material and methods At the Department of Urology, where laparoscopy of the upper abdomen and open RP were performed, a protocol for extraperitoneal LRP was established in 8/2008. Until 5/2011, 154 LRPs have been performed. Urine leakage from a suction drain appeared in 9 cases (5.8%). Permanent active suction (with a machine for Büllae thoracic drainage) of the prevesical space with negative pressure of 7-12 cm of H2O was started immediately. Results Urine leakage started after a mean of 0.9 (0-2) days postoperatively and stopped after a mean of 8.1 (15-42) days. Leakage stopped with only suctioning in 7 cases. In one case, open re-anastomosis was performed on the 7th postoperative day (POD). In another case, ineffective active suction was replaced on the 10th POD by needle vented suction without effect and the leakage stopped following gradual shortening of the drain up to the 15th POD. Conclusions Active suction of the prevesical space seems to be an effective intervention to stop postoperative urine leakage after laparoscopic radical prostatectomy. PMID:23630554

  10. Neonatal Intensive Care Units Nurses’ Attitude Toward Advantages and Disadvantages of Open vs Closed Endotracheal Suction

    PubMed Central

    Valizadeh, Leila; Janani, Raheleh; Janani, Leila; Galechi, Fatemeh

    2014-01-01

    Background: The vital issue of protecting the airway and maintaining ventilation in preterm infants makes tracheal suctioning an important procedure. The decision to use closed or open endotracheal suction method depends on the clinical status of infants and the nurses’ skills and preferences. Objectives: The current study aimed to compare the two methods based on the perceptions of the nurses working in Neonatal Intensive Care Units (NICU). Patients and Methods: A comparative-descriptive study carried out on 35 NICU nurses in Taleghani and Al-Zahra teaching hospitals in Tabriz, Iran, in 2013. Data were collected by self-administered questionnaire (13 Items). Data analysis, including t-test was performed using SPSS Ver. 13. A P ≤ 0.05 was considered statistically sig­nificant. Results: According to the nurses’ point of view, there are differences between characteristics of open and closed endotracheal suctioning methods (P < 0.001). By using closed endotracheal suction, the risk of traumatizing airway, developing pneumonia, increasing intracranial pressure, prolonging emergency suctioning, developing intra-ventricular hemorrhage, blood stream infection, physiological instability and lowering positive end-expiratory pressure (PEEP) are reduced. Meanwhile, lower cost, lower risk of extubation, comfort and easy washing procedure were reported as advantages of open suction. Conclusion: Closed endotracheal suctioning was evaluated to be better than the open method in the preterm neonates. More studies, especially experimental and efficient cost analysis, are recommended. PMID:25414901

  11. Determining standard criteria for endotracheal suctioning in the paediatric intensive care patient: an exploratory study.

    PubMed

    Davies, Kylie; Monterosso, Leanne; Leslie, Gavin

    2011-04-01

    This four-phase mixed method study developed an evidence based "Endotracheal Suction Assessment Tool" (ESAT) as a guide for nurses undertaking "endotracheal tube" (ETT) suction within "Paediatric Intensive Care" (PIC). Phase 1 involved a comprehensive literature review to determine the most commonly used criteria for assessing the need for ETT suction. In Phase 2 an "Endotracheal Suction Questionnaire" (ESQ) was developed to survey experienced PIC nurses in Australia and New Zealand regarding their ETT suction decision making process and validity testing of the ESQ. In Phase 3, the ESQ was administered to target group (n=104). In Phase 4, the empirical evidence generated from this study, based upon the criteria rated by nurses in this study as being most clinically important and essential during the decision making process, determined the ESAT design. Analyses of quantitative results showed a positive correlation between the perceived frequency of use of a criterion and the appropriateness of the assessment. Where a criterion was used less frequently as a clinical indicator for the requirement for ETT suction, participants had a lower regard for this when rating the criterion as a specific single indicator to perform suction. Findings from qualitative data identified six criteria not previously documented within the literature. Further testing and validation of the tool within the PIC setting will determine the clinical viability of the ESAT. PMID:21371887

  12. Transgenic Fish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fish into which foreign DNA is artificially introduced and integrated into their genome are called transgenic fish. Since the development of the first transgenic fish in 1985, techniques to produce transgenic fish have improved tremendously, resulting in the production of genetically modified (GM) ...

  13. Review of Suction Water Content Relationship of Bentonite-Sand Mixtures Considering Temperature Effects

    NASA Astrophysics Data System (ADS)

    Rawat, Abhishek; Zhi Lang, Lin; Baille, Wiebke

    2015-04-01

    Bentonite-sand mixture is one of the candidate sealing/ buffer material for landfills, hazardous and high level radioactive waste repository. The long term satisfactory performance of bentonite sand mixture in terms of load bearing function, sealing function and buffer function is governed by hydro-mechanical response of material under elevated temperature conditions. The suction-water content relationship is one of the key parameter, which govern the thermo-hydro-mechanical behavior of compacted bentonite-sand mixture. This paper presents brief review of suction water content relationships of bentonite-sand mixture considering temperature effects. Numerous parametric models or equations have been developed for representing the soil water characteristics curve i.e. SWCC for isothermal conditions. The most frequently used equations for representing the SWCC are the van Genuchten (1980) and Fredlund and Xing (1994) SWCC equations. Various researchers (Romero et al. 2000; Villar and Lloret, 2004; Tang and Cui, 2005; Agus, 2005; Arifin, 2008) have reported the temperature effect on the water retention behavior of compacted bentonite-sand mixtures. The testing program, results and major conclusions made by above mentioned researchers were discussed in this paper. The changes in hydro-mechanical behavior due to elevated temperature are also discussed based on the suction components of soil which are influenced by temperature. As a general conclusion, total suction of the bentonite-sand mixtures is a function of mixture water content and mixture bentonite content or collectively a function of bentonite water content both at room temperature and at elevated temperature. At a constant temperature, different techniques for measuring suction results in different values of suction depending on accuracy of the sensor and calibration technique used as founded earlier by Agus (2005). The change in total suction due to change in temperature lower than 100 degree C is reversible

  14. Comparison of rectal suction versus rectal tube insertion for reducing abdominal symptoms immediately after unsedated colonoscopy

    PubMed Central

    Liu, Tso-Tsai; Yi, Chih-Hsun; Lei, Wei-Yi; Yu, Hao-Chun; Hung, Jui-Sheng; Chen, Chien-Lin

    2016-01-01

    Background and study aims: Abdominal discomfort and bloating are common symptoms after colonoscopy. We aimed to compare the effects of direct rectal suction with insertion of a rectal tube on reducing abdominal symptoms after unsedated colonoscopy. Patients and methods: Consecutive patients undergoing colonoscopy were randomized to have direct rectal suction or placement of a rectal tube immediately after colonoscopy. Post-procedure abdominal pain and bloating were measured with a 0 – 100 visual analogue scale. All participants ranked their satisfaction with either direct rectal suction or insertion of a rectal tube. Results: Abdominal pain and bloating were significantly reduced by direct rectal suction and placement of a rectal tube at 1 minute (both P < 0.05) and 3 minutes (both P < 0.05) after the colonoscopy. Direct rectal suction significantly reduced abdominal pain at 1 minute (P = 0.001) and 3 minutes (P = 0.005) after colonoscopy compared with rectal tube insertion. Bloating was significantly lower in patients with direct rectal suction compared to those with rectal tube insertion at 1 minute (P = 0.03) after colonoscopy. Greater satisfaction was found in patients with direct rectal suction compared to those with rectal tube insertion (P = 0.009). Conclusion: Direct rectal suction is more effective than rectal tube placement in reducing abdominal symptoms immediately after colonoscopy. Our study suggests that direct rectal suction is useful in providing relief of symptoms when patients are having difficulty expelling air or are experiencing abdominal symptoms following colonoscopy. PMID:27336061

  15. Theoretical investigation of maintaining the boundary layer of revolution laminar using suction slits in incompressible flow

    NASA Technical Reports Server (NTRS)

    Thiede, P.

    1978-01-01

    The transition of the laminar boundary layer into the turbulent state, which results in an increased drag, can be avoided by sucking of the boundary layer particles near the wall. The technically-interesting case of sucking the particles using individual slits is investigated for bodies of revolution in incompressible flow. The results of the variational calculations show that there is an optimum suction height, where the slot separations are maximum. Combined with favorable shaping of the body, it is possible to keep the boundary layer over bodies of revolution laminar at high Reynolds numbers using relatively few suction slits and small amounts of suction flow.

  16. A law of the wall for turbulent boundary layers with suction: Stevenson's formula revisited

    NASA Astrophysics Data System (ADS)

    Vigdorovich, Igor

    2016-08-01

    The turbulent velocity field in the viscous sublayer of the boundary layer with suction to a first approximation is homogeneous in any direction parallel to the wall and is determined by only three constant quantities — the wall shear stress, the suction velocity, and the fluid viscosity. This means that there exists a finite algebraic relation between the turbulent shear stress and the longitudinal mean-velocity gradient, using which as a closure condition for the equations of motion, we establish an exact asymptotic behavior of the velocity profile at the outer edge of the viscous sublayer. The obtained relationship provides a generalization of the logarithmic law to the case of wall suction.

  17. Feeding guilt.

    PubMed

    Byrom, Anna

    2013-03-01

    Breastfeeding is increasingly equated to ideologies of the 'good mother' in our society in response to a growing body of evidence identifying its benefits. Women who choose not to or are unable to breastfeed can experience a sense of guilt in response to cultural expectations that 'breast is best'. These negative feelings can impact upon their adaptation to and enjoyment of motherhood. This discussion paper examines the experience of maternal guilt with specific reference to infant feeding. An exploration of the reasons mothers may feel guilty about their feeding experiences is offered. Finally some suggestions are made about how midwives and breastfeeding advocates might improve care for mothers' emotional wellbeing. PMID:23590082

  18. A Morphospace for Reef Fishes: Elongation Is the Dominant Axis of Body Shape Evolution

    PubMed Central

    Claverie, Thomas; Wainwright, Peter C.

    2014-01-01

    Tropical reef fishes are widely regarded as being perhaps the most morphologically diverse vertebrate assemblage on earth, yet much remains to be discovered about the scope and patterns of this diversity. We created a morphospace of 2,939 species spanning 56 families of tropical Indo-Pacific reef fishes and established the primary axes of body shape variation, the phylogenetic consistency of these patterns, and whether dominant patterns of shape change can be accomplished by diverse underlying changes. Principal component analysis showed a major axis of shape variation that contrasts deep-bodied species with slender, elongate forms. Furthermore, using custom methods to compare the elongation vector (axis that maximizes elongation deformation) and the main vector of shape variation (first principal component) for each family in the morphospace, we showed that two thirds of the families diversify along an axis of body elongation. Finally, a comparative analysis using a principal coordinate analysis based on the angles among first principal component vectors of each family shape showed that families accomplish changes in elongation with a wide range of underlying modifications. Some groups such as Pomacentridae and Lethrinidae undergo decreases in body depth with proportional increases in all body regions, while other families show disproportionate changes in the length of the head (e.g., Labridae), the trunk or caudal region in all combinations (e.g., Pempheridae and Pinguipedidae). In conclusion, we found that evolutionary changes in body shape along an axis of elongation dominates diversification in reef fishes. Changes in shape on this axis are thought to have immediate implications for swimming performance, defense from gape limited predators, suction feeding performance and access to some highly specialized habitats. The morphological modifications that underlie changes in elongation are highly diverse, suggesting a role for a range of developmental processes

  19. Breast Feeding.

    ERIC Educational Resources Information Center

    International Children's Centre, Paris (France).

    This set of documents consists of English, French, and Spanish translations of four pamphlets on breast-feeding. The pamphlets provide information designed for lay persons, academics and professionals, health personnel and educators, and policy-makers. The contents cover health-related differences between breast and bottle milk; patterns of…

  20. Tube Feedings.

    ERIC Educational Resources Information Center

    Plummer, Nancy

    This module on tube feedings is intended for use in inservice or continuing education programs for persons who work in long-term care. Instructor information, including teaching suggestions and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then provided. A brief discussion follows…

  1. 7 CFR 760.211 - Farm-raised fish payment calculations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Farm-raised fish payment calculations. 760.211 Section..., Honeybees, and Farm-Raised Fish Program § 760.211 Farm-raised fish payment calculations. (a) An eligible farm-raised fish producer may receive payments for fish feed losses due to an eligible adverse...

  2. 7 CFR 760.211 - Farm-raised fish payment calculations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Farm-raised fish payment calculations. 760.211 Section..., Honeybees, and Farm-Raised Fish Program § 760.211 Farm-raised fish payment calculations. (a) An eligible farm-raised fish producer may receive payments for fish feed losses due to an eligible adverse...

  3. 7 CFR 760.211 - Farm-raised fish payment calculations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 7 2013-01-01 2013-01-01 false Farm-raised fish payment calculations. 760.211 Section..., Honeybees, and Farm-Raised Fish Program § 760.211 Farm-raised fish payment calculations. (a) An eligible farm-raised fish producer may receive payments for fish feed losses due to an eligible adverse...

  4. 7 CFR 760.211 - Farm-raised fish payment calculations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 7 2012-01-01 2012-01-01 false Farm-raised fish payment calculations. 760.211 Section..., Honeybees, and Farm-Raised Fish Program § 760.211 Farm-raised fish payment calculations. (a) An eligible farm-raised fish producer may receive payments for fish feed losses due to an eligible adverse...

  5. Does Medical Evidence Support Routine Oronasopharyngeal Suction at Delivery?

    PubMed Central

    Evans, M. Blake

    2016-01-01

    Oronasopharyngeal suction (ONPS) is regularly performed in neonates at delivery in many hospitals across the country today. Although ONPS is a technique that has essentially become habitual for most obstetricians, its theorized usefulness to help promote expeditious lung aeration after delivery by removal of amniotic fluid, meconium, mucus and blood that may otherwise be aspirated by the newborn, is currently not recommended. ONPS can cause vagal stimulation-induced bradycardia and thus apnea, and can cause iatrogenic infection due to mucous membrane injury. Multiple studies that have been performed comparing routine use of ONPS to no intervention controls indicate that newborns receiving ONPS took a longer time to achieve normal oxygen saturations, caused apneic episodes, and caused disturbances in heart rate (mainly bradycardia) compared to the control groups. Although the ONPS groups revealed no significantly different APGAR scores at 1 and 5 minutes, the ONPS groups took longer than the control group to reach an arterial oxygen saturation greater than or equal to 92% in the first minutes of life. Currently, Neonatal Resuscitation Program guidelines discourage the use of routine OPNS during or after delivery with clear or meconium-stained amniotic fluid and in the absence of obvious obstruction. Furthermore, this manuscript highlights various literature sources revealing that the routine use of ONPS at the time of delivery can cause more harm than good, if any good at all. PMID:27328554

  6. Effects of infusion of cardiotomy suction blood during extracorporeal circulation for coronary artery bypass surgery.

    PubMed

    Okies, J E; Goodnight, S H; Litchford, B; Connell, R S; Starr, A

    1977-09-01

    The effects of infusion of cardiotomy suction blood during extracorporeal circulation were evaluated in 15 patients undergoing coronary artery bypass surgery without the use of a left ventricular vent. In Group I all cardiotomy suction blood was discarded. In Groups II and III cardiotomy suction blood was reinfused without and with Dacron wool filtration, respectively. Marked hematologic changes were noted in the pericardial samples which also were reflected in oxygenator samples obtained at the end of bypass. Although postoperative bleeding was significantly greater in patients from Group II as compared to Group I, no differences were seen in total intraoperative and postoperative transfusion requirements. No patient required reoperation for bleeding. Recirculation of larger volumes of cardiotomy suction blood potentially could contribute to bleeding problems in the immediate postoperative period. PMID:142868

  7. Fulminant adult respiratory distress syndrome after suction lipectomy. A case report.

    PubMed

    Boezaart, A P; Clinton, C W; Braun, S; Oettle, C; Lee, N P

    1990-12-01

    The adult respiratory distress syndrome developing within 24 hours in a patient who underwent suction lipectomy for body contouring under general anaesthesia is reported. During surgery, in which a total of 1.3 l of suction matter was removed, the patient became haemodynamically unstable and mildly hyperthermic. Subsequently, clinical signs and symptoms of the fat embolism syndrome developed. Aggressive haemodynamic and respiratory support over an 8-day period resulted in patient survival. Malignant hyperthermia was excluded as cause for the clinical presentation on muscle biopsy and in vitro caffeine contracture studies. Although usually complication-free, suction lipectomy may be associated with life-threatening incidents. Even suction volumes as low as 1.3 l have potential hazards, therefore the procedure merits regular postoperative observation and re-assessment. PMID:2251620

  8. Shock wave boundary layer interaction on suction side of compressor profile in single passage test section

    NASA Astrophysics Data System (ADS)

    Flaszynski, Pawel; Doerffer, Piotr; Szwaba, Ryszard; Kaczynski, Piotr; Piotrowicz, Michal

    2015-11-01

    The shock wave boundary layer interaction on the suction side of transonic compressor blade is one of the main objectives of TFAST project (Transition Location Effect on Shock Wave Boundary Layer Interaction). In order to investigate the flow structure on the suction side of a profile, a design of a generic test section in linear transonic wind tunnel was proposed. The experimental and numerical results for the flow structure investigations are shown for the flow conditions as the existing ones on the suction side of the compressor profile. Near the sidewalls the suction slots are applied for the corner flow structure control. It allows to control the Axial Velocity Density Ratio (AVDR), important parameter for compressor cascade investigations. Numerical results for Explicit Algebraic Reynolds Stress Model with transition modeling are compared with oil flow visualization, schlieren and Pressure Sensitive Paint. Boundary layer transition location is detected by Temperature Sensitive Paint.

  9. A parametric optimization procedure for the suction system of reciprocating compressors

    NASA Astrophysics Data System (ADS)

    Ferreira, W. M.; Silva, E.; Deschamps, C. J.

    2015-08-01

    The design of the suction system of compressors is of fundamental importance for efficiency and reliability. This paper reports a method developed to optimize the suction system of a reciprocating compressor, by using the genetic algorithm NSGA-II. The isentropic and volumetric efficiencies are used as objective functions, while the bending fatigue stress is used as a constraint to meet valve reliability. A simulation model of the compression cycle was coupled to the optimization procedure, with correlations for flow and force effective areas in terms of geometric parameters of the suction valve. Valve dynamics was numerically solved via the finite element method. The proposed optimization procedure was applied to a reciprocating compressor adopted for household refrigeration, identifying suction system geometries more efficient than the original design.

  10. Replacing fish meal by food waste to produce lower trophic level fish containing acceptable levels of polycyclic aromatic hydrocarbons: Health risk assessments.

    PubMed

    Cheng, Zhang; Mo, Wing-Yin; Lam, Cheung-Lung; Choi, Wai-Ming; Wong, Ming-Hung

    2015-08-01

    This study aimed at using different types of food wastes (mainly containing cereal [food waste A] and meat meal [food waste B]) as major sources of protein to replace the fish meal used in fish feeds to produce quality fish. The traditional fish farming model used to culture low trophic level fish included: bighead, (Hypophthalmichthys nobilis), grass carp, (Ctenopharyngodon idellus), and mud carp, (Cirrhinus molitorella) of omnivorous chain. The results indicated that grass carp and bighead carp fed with food waste feeds were relatively free of PAHs. The results of health risk assessment showed that the fish fed with food waste feeds were safe for consumption from the PAHs perspective. PMID:25880597

  11. [Application of deactivating properties of some sorbents in aquaculture feed production].

    PubMed

    Vasukevich, T A; Nitievskaya, L S

    2014-01-01

    The possibility and effectiveness of application of selective sorbents for fish feed production in aquaculture in the area exposed to the radioactive pollution were studied. The investigations of the fish feed deactivating properties with additives of ferrocyn and potassium alginate, and magnesium on whitefish fry-fingerlings and yearlings were carried out. The study has shown that the ferrocyn performance is greater than 99% regardless of the fish age. 1% ferrocyn addition to feed allows increasing the acceptable concentration of feed compo- nents polluted by the above norm cesium radionuclide up to 20 times. The alginate additives in feed provide almost double decrease in the activity of fish tissues. The optimally effective alginate dose should exceed the calcium concentration in feed up to 4 times. It was found that utilization of the feedstock (fish meal, crops and legumes, oil meal and oil cake) polluted by radionuclides is possible in combined aquaculture feed pro- duction. The application of sorbents in feed will allow increasing the amount permissible for use of the feed components polluted above the norm; ensure the radiation safety of feed and, finally, the protection of aquatic biological resources from radioactive contamination. It is shown that the sorbent additive in feed is also jus- tified in case of fish farming in closed waters affected by radioactive pollution. Feeding by mixed fodder with the sorbent additives prevents fish from radionuclide intake from natural food sources. PMID:25980288

  12. Secondary subharmonic instability of boundary layers with pressure gradient and suction

    NASA Technical Reports Server (NTRS)

    El-Hady, Nabil M.

    1988-01-01

    Three-dimensional linear secondary instability is investigated for boundary layers with pressure gradient and suction in the presence of a finite amplitude TS wave. The focus is on principal parametric resonance responsible for a strong growth of subharmonics in a low disturbance environment. Calculations are presented for the effect of pressure gradients and suction on controlling the onset and amplification of the secondary instability.

  13. Experiments with an Airfoil from which the Boundary Layer Is Removed by Suction

    NASA Technical Reports Server (NTRS)

    Ackeret, J; Betz, A; Schrenk, O

    1926-01-01

    Our attempts to improve the properties of airfoils by removing the boundary layer by suction, go back to 1922. The object of the suction is chiefly to prevent the detachment of the boundary layer from the surface of the airfoil. At large angles of attack, such detachment prevents the attainment of the great lift promised by the theory, besides greatly increasing the drag, especially of thick airfoils. This report gives results of those experiments.

  14. VORCAM: A computer program for calculating vortex lift effect of cambered wings by the suction analogy

    NASA Technical Reports Server (NTRS)

    Lan, C. E.; Chang, J. F.

    1981-01-01

    A user's guide to an improved version of Woodward's chord plane aerodynamic panel computer code is presumed. The guide can be applied to cambered wings exhibiting edge separated flow, including those with leading edge vortex flow at subsonic and supersonic speeds. New orientations for the rotated suction force are employed based on the momentum principal. The supersonic suction analogy method is improved by using an effective angle of attack defined through a semiempirical method.

  15. Numerical Studies on a Rotor with Distributed Suction for Noise Reduction

    NASA Astrophysics Data System (ADS)

    Lutz, Thorsten; Arnold, Benjamin; Wolf, Alexander; Krämer, Ewald

    2014-06-01

    Minimizing the flow-induced noise is an important issue in the design of modern onshore wind turbines. There is a number of proven passive means to reduce the aeroacoustic noise, such as the implementation of serrations, porous trailing edges or the aeroacoustic airfoil design. The noise emission can be further reduced by active flow control techniques. In the present study the impact of distributed boundary layer suction on the noise emission of an airfoil and a complete rotor is investigated. Aerodynamic and aeroacoustic wind tunnel tests were performed for the NACA 64-418 airfoil and supplemented by numerical calculations. The aeroacoustic analyses have been conducted by means of the institute's Rnoise prediction scheme. The 2D studies have shown that noise reductions of 5 dB can be achieved by suction at moderate mass flow rates. To study the impact of three-dimensional effects numerical investigations have been conducted on the example of the generic NREL 5MW rotor with suction applied in the outer part of the blade. The predictions for the complete rotor provided smaller benefits compared to those for the isolated airfoil, mainly because the examined suction configurations were not optimized with respect to the extent of the suction patch and suction distribution.

  16. The role of subgaleal suction drain placement in chronic subdural hematoma evacuation

    PubMed Central

    Yadav, Yad Ram; Parihar, Vijay; Chourasia, Ishwar D.; Bajaj, Jitin; Namdev, Hemant

    2016-01-01

    Introduction: There is lack of uniformity about the preferred surgical treatment, role of drain, and type of drain among various surgeons in chronic subdural hematoma (CSDH). The present study is aimed to evaluate role of subgaleal drain. Materials and Methods: This was a prospective study of 260 patients of CSDH treated surgically. Burr-hole irrigation with and without suction drain was done in 140 and 120 patients, respectively. Out of 120 patients without suction drain 60 each were managed by single and two burr holes. Pre- and postoperative GCS was recorded. Recurrent hematomas, CSDH secondary to tumor, due to intracranial hypotension, coagulopathy, children below 18 years, and patients treated by twist drill craniostomy or craniotomy were excluded. Subgaleal closed-system drainage with low negative pressure was used. Results: Age of the patients ranged from 18 to 75 years with mean age of 57 years. There were 9, 47, 204 patients in GCS of 3-8, 9-12, and 13-15, respectively. Both the groups were comparable in terms of age, etiology, gender, and neurological status. There was no difference in the mortality in both the group. The recurrence and postoperative pneumocephalus was significantly less in suction drain group as compared to without drain group. There was no infection or any other complication related to suction drainage. Conclusion: Subgaleal closed suction drainage was safe, simple, and effective in the management of CSDH. Recurrence rate was low in the suction drain group. PMID:27366247

  17. Influence of suction cycles on the soil fabric of compacted swelling soil

    NASA Astrophysics Data System (ADS)

    Nowamooz, Hossein; Masrouri, Farimah

    2010-12-01

    The soil fabric plays an important role in complex hydromechanical behaviour of the expansive soils. This article addresses the influence of the wetting and drying paths on the soil fabric of compacted bentonite and silt mixtures at two different initial dry densities corresponding to loose and dense states. To obtain the hydric response of the soil, two suction imposition techniques were used: osmotic technique for the suction range less than 8.5 MPa and the vapour equilibrium or the salt solution technique for the suction range between 8.5 and 287.9 MPa. Additionally, the soil fabric analysis was performed using mercury intrusion porosimetry (MIP) and nitrogen gas adsorption (BET) techniques. The dense samples produced cumulative swelling strains during the suction cycles, while shrinkage was observed for the loose samples. The suction cycles induced an equilibrium state indicative of the elastic behaviour of the samples. The soil fabric analysis showed that regardless of the soil's initial state (loose or dense), the samples obtained the same soil fabric at the equilibrium state. The experimental results illustrated also the existence of an elastic void ratio ( e0el) where the compacted soils at this state present an elastic hydric behaviour during the successive suction cycles.

  18. Design and experimental performance of short curved wall diffusers with axial symmetry utilizing slot suction

    NASA Technical Reports Server (NTRS)

    Yang, T.; Hudson, W. G.; Nelson, C. D.

    1973-01-01

    The feasibility of designing short curved wall axially symmetrical subsonic diffusers utilizing suction through slots in the diffuser walls to prevent flow separation was investigated. A potential flow analysis was made, and a digital computer program was written for determining the diffuser wall contour for prescribed boundary conditions. The flow field included branch flow so that the suction slot geometry could be a part of the diffuser design. One bell shaped diffuser and three annular diffusers with area ratios of either 2.5:1 or 3:1 were designed, fabricated, and tested. Minimum suction requirements of metastable operation ranged from 6.3 percent to 12 percent when operating with inlet air velocities in the 1000 to 250 ft/sec (30 to 76 m/sec) range. For stable operation suction rates from 10 percent to 22 percent were required. In all cases the diffuser effectiveness was above 95 percent based on the conventional definition, and from 81 percent to 94 percent when the suction loss was accounted for. The exit velocity profiles were virtually flat with no more than + or - 9% variation over 95 percent of the exit area when operated with sufficient suction to prevent flow separation.

  19. Performance of a short annular dump diffuser using wall trailing-edge suction

    NASA Technical Reports Server (NTRS)

    Juhasz, A. J.

    1974-01-01

    A short annular dump (abrupt flow area change) diffuser was tested with suction through wall trailing-edge slots at inlet Mach numbers of 0.19 and 0.27 and at near ambient inlet temperature and pressure, with suction flow varied from zero to 10 percent of the inlet air mass-flow rate. The overall ratio of diffuser exit area to inlet area was 4.0, and the ratio of length to inlet height was 2.0. By applying suction flow separately on either wall or to both walls simultaneously, the original annular jet profile could be altered to either a hub- or tip-biased profile. Diffuser effectiveness was increased from about 25 percent with no suction to 50 percent at 6 percent outer-wall suction and to 52 percent at a combined suction rate on both walls of 10.25 percent. At the same time, diffuser total pressure loss was reduced by one-fourth.

  20. Fish Dishes.

    ERIC Educational Resources Information Center

    Derby, Marie

    2003-01-01

    Describes an art project that was inspired by Greek pottery, specifically dishes shaped as fish. Explains that fourth-grade students drew a fish shape that was later used to create their clay version of the fish. Discusses how the students examined the pottery to make decisions about color and design. (CMK)

  1. Feeding kinematics of juvenile swellsharks, Cephaloscyllium ventriosum

    PubMed

    Ferry-Graham

    1997-01-01

    To investigate how feeding behaviors change with prey size, high-speed video recording was used to examine the kinematics of prey capture and transport in 1-year-old swellsharks Cephaloscyllium ventriosum (Scyliorhinidae: Carchariniformes) feeding on two differently sized prey items. Prey capture in these sharks generally consisted of an initially ram-dominated capture bite, one or more manipulation bites, a holding phase during which the food was held in the teeth of the shark, and then suction-dominated prey transport. During initial capture and transport, most of the water taken in is forced back out of the mouth anteriorly rather than continuing posteriorly out through the gill openings. Dye experiments in which dye-perfused prey items were ingested by the sharks confirm this observation; distinct jets of colored water were video-taped as they were ejected from the mouth. Very late in prey transport, a bolus of water is ejected through the gill slits; however, by this time, the majority of water appears already to have exited the buccal cavity through the mouth. Such patterns were observed for sharks feeding on both small and large prey items. Although a basic pattern of prey capture and transport was regularly repeated among strikes, kinematic patterns during prey capture and transport were variable both within and among individuals, indicating that prey acquisition is not tightly controlled. However, the amount of variability was similar among prey sizes. In addition, there were no detectable changes in behavior due to prey item size. Ram-suction index values confirmed that similar capture modes were being utilized for both prey sizes. PMID:9319118

  2. [Endotracheal suctioning of secretions: effects of instillation of normal serum].

    PubMed

    Lerga, C; Zapata, M A; Herce, A; Martínez, A; Margall, M A; Asiain, M C

    1997-01-01

    Normal saline (NS) instillations in the trachea during the technique of endotracheal suctioning is an habitual practice although there is still some controversy about the benefits and harmful effects caused by this practice. This study was carried out with the objective to compare the effects of instillation or no instillation of NS during the aspiration technique on the oxygenation, amount of secretion obtained, and hemodynamical and ventilatory parameters. We studied 176 en dotracheal aspirations recorded in the post-operatory of 25 patients without previous pulmonary disease who underwent heart surgery. The aspiration was performed every two hours, according to the protocol of the study. Each patient was its own case and control, so the same patient was aspired altern actively; with and without NS instillation alternatively. Hemodynamical parameters (arterial blood pressure, heart rate), ventilatory parameters (fidal volume, peak inspiratory pressure, respiratory rate) and oxygenation parameters (PaO2, SaO2, SpO2) were analysed in all the samples. The amount of secretion obtained with both techniques was evaluated using weight calculus and total proteins. When analysing the results, we observed that the technique of en dotracheal aspiration causes increases of the Average Arterial Pressure; when NS is used in the aspiration there is a statistically significant decrease of PaO2. In the evaluation of the amount of secretions we obtained similar amounts with both techniques. Taking all this into account we recommend the elimination of systematical instillation of physiological serum from the protocols of endotracheal aspiration during this technique. PMID:9481276

  3. Dietary burden calculations relating to fish metabolism studies.

    PubMed

    Schlechtriem, Christian; Pucher, Johannes; Michalski, Britta

    2016-03-30

    Fish farming is increasingly dependent on plant commodities as a source of feed leading to an increased risk for pesticide residues in aquaculture diets and consequently their transfer into aquaculture food products. The European pesticide regulation requires fish metabolism and fish feeding studies where residues in fish feed exceed 0.1 mg kg(-1) of the total diet (dry weight basis) to enable the setting of appropriate maximum residue levels in fish commodities. Fish dietary burden calculation is therefore an important prerequisite to decide on further experimental testing as part of the consumer risk assessment. In this review, the different aquaculture production systems are compared with regard to their specific feeding practices and the principles of dietary burden calculation are described. PMID:26749492

  4. Nonnutrient Components of Fish Diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Though the various dietary nutrients are the primary concerns of nutritionists when formulating feeds for intensively cultured tilapia, the inclusion of dietary components that do not have nutritional value can have profound effects on the performance of fish fed these diets. These components may be...

  5. Infant feeding practices in Malaysia.

    PubMed

    Chen, S T

    1978-12-01

    Retrospective nutritional data on 100 children, aged 6 months to 2 1/2 years, who were admitted to the University Hospital in Kuala Lumpur, Malaysia, was obtained by interviewing the mothers of the children. Analysis of the data revealed that 1) only 49% of the children were breast-fed as infants; 2) 50% of the mothers who did breast-feed discontinued breast-feeding before the children were 3 months old; and 3) the weaning diet of at least 1/3 of the children was inadequate. 18% of the children were Malays, 49% were Chinese, and 33% were Indian. The proportion of breast-fed children was highest among the Malays and lowest among the Chinese. Mothers with higher incomes tended to stop breast-feeding earlier than mothers with lower incomes. 67% of the women said they stopped breast-feeding due to inadequate lactation. Most of the children received supplementary foods at relatively early ages. 50% of the infants received starchy foods by the time they were 3 1/2 months old, and 50% received fruit or fruit juice by the time they were 3 1/2 months old. Vegetable products, meat, fish, and eggs were not added to the diet until the children were considerably older. Recommendations, based on the study findings, were 1) hospitals should discontinue the practice of deferring breast-feeding initiation for 24 hours after delivery; 2) mothers should be encouraged to breast-feed fully; and 3) health personnel should discourage the widespread use of costly precooked cereals for supplementary feeding. Tables depicted 1) the frequency distribution of the 100 children by income and by milk feeding patterns according to ethnic affiliation and 2) the cost of serving precooked cereals as compared to the cost of serving home cooked meals. PMID:755160

  6. Endotracheal Suctioning in Preterm Infants Using Four-Handed versus Routine Care

    PubMed Central

    Cone, Sharon; Pickler, Rita H.; Grap, Mary Jo; McGrath, Jacqueline; Wiley, Paul M.

    2013-01-01

    Objective To evaluate the effect of four-handed care on preterm infants’ physiologic and behavioral responses to and recovery from endotracheal suctioning versus routine endotracheal (ETT) suctioning. Design Randomized crossover design with infants as their own controls. Setting Single-family-room newborn intensive care unit in an academic health center. Participants Ten intubated infants on conventional ventilation with inline suctioning who were fewer than 37 weeks gestation at birth, and less than one week of age. Methods Each infant was observed twice on a single day. One observation involved routine ETT suctioning and one involved four-handed care. Physiologic and behavioral response data were collected. Results No differences were noted when comparing baseline heart rate (HR) or oxygen saturation (SpO2) data to those obtained during and after suctioning while in the routine care condition. In the four-handed care condition, mean SpO2 increased from preobservation 95.49 to during observation saturation 97.75 (p = .001). Salivary cortisol levels did not differ between groups at baseline or postsuctioning. No significant difference in behavior state was observed between the two conditions. More stress and defense behaviors occurred postsuctioning when infants received routine care as opposed to four-handed care (p = .001) and more self-regulatory behaviors were exhibited by infants during (p = .019) and after suctioning (p = .016) when receiving four-handed care. No statistical difference was found in the number of monitor call-backs postsuctioning. Conclusions Four-handed care during suctioning was associated with a decrease in stress and defense behaviors and an increase in self-regulatory behaviors. PMID:23316894

  7. Boundary layer modification by means of wall suction and the effect on the wake behind a rectangular forebody

    NASA Astrophysics Data System (ADS)

    Trip, Renzo; Fransson, Jens H. M.

    2014-12-01

    The wake characteristics of a two-dimensional rectangular forebody with a smooth leading edge and a blunt trailing edge are investigated. Wall suction is applied along the forebody in order to modify the developing boundary layer. An initially laminar boundary layer subject to suction yields an asymptotic suction boundary layer at the trailing edge of the body, whereas a high enough suction coefficient relaminarizes an initially turbulent boundary layer. The critical suction velocity required to achieve this significant modification of the boundary layer properties is typically in the order of 1% of the free-stream velocity, where the critical suction coefficient depends on the Reynolds number. We show that a thinner boundary layer induces a higher vortex shedding frequency and a lower base pressure. Furthermore, the boundary layer state, laminar or turbulent, has a significant influence on the wake. For example, the Strouhal number based on the effective body thickness is being reduced by 25% from laminar to turbulent inlet conditions.

  8. Assessment of vector/host contact: comparison of animal-baited traps and UV-light/suction trap for collecting Culicoides biting midges (Diptera: Ceratopogonidae), vectors of Orbiviruses

    PubMed Central

    2011-01-01

    Background The emergence and massive spread of bluetongue in Western Europe during 2006-2008 had disastrous consequences for sheep and cattle production and confirmed the ability of Palaearctic Culicoides (Diptera: Ceratopogonidae) to transmit the virus. Some aspects of Culicoides ecology, especially host-seeking and feeding behaviors, remain insufficiently described due to the difficulty of collecting them directly on a bait animal, the most reliable method to evaluate biting rates. Our aim was to compare typical animal-baited traps (drop trap and direct aspiration) to both a new sticky cover trap and a UV-light/suction trap (the most commonly used method to collect Culicoides). Methods/results Collections were made from 1.45 hours before sunset to 1.45 hours after sunset in June/July 2009 at an experimental sheep farm (INRA, Nouzilly, Western France), with 3 replicates of a 4 sites × 4 traps randomized Latin square using one sheep per site. Collected Culicoides individuals were sorted morphologically to species, sex and physiological stages for females. Sibling species were identified using a molecular assay. A total of 534 Culicoides belonging to 17 species was collected. Abundance was maximal in the drop trap (232 females and 4 males from 10 species) whereas the diversity was the highest in the UV-light/suction trap (136 females and 5 males from 15 species). Significant between-trap differences abundance and parity rates were observed. Conclusions Only the direct aspiration collected exclusively host-seeking females, despite a concern that human manipulation may influence estimation of the biting rate. The sticky cover trap assessed accurately the biting rate of abundant species even if it might act as an interception trap. The drop trap collected the highest abundance of Culicoides and may have caught individuals not attracted by sheep but by its structure. Finally, abundances obtained using the UV-light/suction trap did not estimate accurately Culicoides

  9. Feeding rates and under-ice foraging strategies of the smallest lunge filter feeder, the Antarctic minke whale (Balaenoptera bonaerensis).

    PubMed

    Friedlaender, A S; Goldbogen, J A; Nowacek, D P; Read, A J; Johnston, D; Gales, N

    2014-08-15

    Body size and feeding mode are two fundamental characteristics that determine foraging performance and ecological niche. As the smallest obligate lunge filter feeders, minke whales represent an ideal system for studying the physical and energetic limits of filter feeding in endotherms. We used multi-sensor suction cup tags to quantify the feeding performance of Antarctic minke whales. Foraging dives around and beneath sea ice contained up to 24 lunges per dive, the highest feeding rates for any lunge-feeding whale. Their small size allows minke whales access to krill in sea-ice environments not easily accessible to larger baleen whales. Furthermore, their ability to filter feed provides an advantage over other smaller sympatric krill predators such as penguins and seals that feed on individual prey. The unique combination of body size, feeding mechanism and sea-ice habitat of Antarctic minke whales defines a previously undocumented energetic niche that is unique among aquatic vertebrates. PMID:25122916

  10. Comparing the effect of open and closed endotracheal suctioning on pain and oxygenation in post CABG patients under mechanical ventilation

    PubMed Central

    Mohammadpour, Ali; Amini, Shahram; Shakeri, Mohammad Taghi; Mirzaei, Sahereh

    2015-01-01

    Background: The aim of this study was to compare changes in pain, oxygenation, and ventilation following endotracheal suctioning with open and closed suctioning systems in post coronary artery bypass grafting (CABG) patients. Materials and Methods: 130 post CABG mechanically ventilated patients were randomly allocated to undergo either open (n = 75) or closed (n = 55) endotracheal suctioning for 15 s. The patients received 100% oxygen for 1 min before and after suctioning. Pain score using critical-care pain objective tool (CPOT) was compared during suctioning between the two groups. Arterial oxygen pressure (PaO2), PaO2 to fraction of inspired oxygen (FiO2) (PF) ratio, and arterial carbon dioxide pressure (PaCO2) were compared at baseline and 5 min after suctioning. Peripheral oxygen saturation (SpO2) was compared at baseline, during suctioning, and at 1 min interval after suctioning for 5 min between the two groups. Results: The patients were the same with regard to CPOT scores, i.e. 3.21 (1.89) and 2.94 (1.56) in the open and closed suctioning systems, respectively. SpO2 did not change significantly between the two groups. Changes in PaO2 and PF ratio was more significant in the open than in the closed system (P = 0.007). Patients in the open group had a higher PaCO2 than those in the closed group, i.e. 40.54 (6.56) versus 38.02 (6.10), and the P value was 0.027. Conclusions: Our study revealed that patients’ pain and SpO2 changes are similar following endotracheal suctioning in both suctioning systems. However, oxygenation and ventilation are better preserved with closed suctioning system. PMID:25878695

  11. Effects of dietary fiber concentrations supplied by corn bran on feed intake growth and feed efficiency of channel catfish Ictalurus punctatus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present study examined the effects of dietary fiber and digestible energy on the feed intake, growth, and feed efficiency of juvenile channel catfish Ictalurus punctatus. Fish with an initial weight of 9.8 ± 0.1 g/fish (mean ± SD) were stocked in 110-L flow-through aquariums and fed for 9 weeks ...

  12. Effect of Propellant Feed System Coupling and Hydraulic Parameters on Analysis of Chugging

    NASA Technical Reports Server (NTRS)

    Wood, Don J.; Dorsch, Robert G.

    1967-01-01

    A digital distributed parameter model was used to study the effects of propellant-feed- system coupling and various hydraulic parameters on the analytical prediction of chugging instabilities. Coupling between the combustion chamber and feed system was controlled by varying the compliance of the injector-dome region. The coupling with the feed system above the pump was varied by changing the amount of cavitation compliance at the pump inlet. The stability limits and chugging frequencies proved to be strongly dependent on the degree of feed-system coupling. The maximum stability condition occurred with intermediate coupling. Under conditions of a high degree of feed-system-combustor coupling, the stability limits and chugging frequencies were primarily dependent on the feed-system characteristics; the responses were characterized by beating patterns. For the system analyzed, the pump suction line had little effect on the stability limits or chugging frequencies. Beating, present under the condition of near zero injector -dome compliance, was eliminated when the suction line was decoupled by employing a sufficiently high value of pump-inlet compliance. Under conditions of maximum feed-system coupling, the magnitude and distribution of line losses in the discharge line had a significant effect on the stability limits but had negligible effect on the chugging frequency and beating characteristics. Also, the length of the discharge line greatly affected the stability limits, chugging frequency, and beating characteristics. The length of the suction line, however, had little effect on the stability limits and chugging frequency but did influence the beating pattern. A resistive-shunt device attached to the pump discharge line to suppress chugging was investigated. The analysis showed that the device was effective under conditions of high feed-system coupling.

  13. Fish Rhabdoviruses

    USGS Publications Warehouse

    Kurath, G.; Winton, J.

    2008-01-01

    Many important viral pathogens of fish are members of the family Rhabdoviridae. The viruses in this large group cause significant losses in populations of wild fish as well as among fish reared in aquaculture. Fish rhabdoviruses often have a wide host and geographic range, and infect aquatic animals in both freshwater and seawater. The fish rhabdoviruses comprise a diverse collection of isolates that can be placed in one of two quite different groups: isolates that are members of the established genusNovirhabdovirus, and those that are most similar to members of the genus Vesiculovirus. Because the diseases caused by fish rhabdoviruses are important to aquaculture, diagnostic methods for their detection and identification are well established. In addition to regulations designed to reduce the spread of fish viruses, a significant body of research has addressed methods for the control or prevention of diseases caused by fish rhabdoviruses, including vaccination. The number of reported fish rhabdoviruses continues to grow as a result of the expansion of aquaculture, the increase in global trade, the development of improved diagnostic methods, and heightened surveillance activities. Fish rhabdoviruses serve as useful components of model systems to study vertebrate virus disease, epidemiology, and immunology.

  14. Fish flavor.

    PubMed

    Kawai, T

    1996-02-01

    This article reviews features of flavor in three groups of fishes and summarizes them as follows: (1) fresh saltwater fish are nearly odorless because they contain a small quantity of volatiles; (2 freshwater fish give off pyrrolidine and earthy-odor compounds, which are responsible for their maturity and surrounding water pollution, and (3) euryhaline fish exhibit a variety of unsaturated carbonyls and alcohols derived from enzymatic and nonenzymatic oxidation of polyunsaturated fatty acids (PAs). These features are discussed, as are the effects of different enzymatic activities on PA oxidation and the effects of pH on mechanisms of formation of the volatiles. The monotonous volatile constitution of saltwater fish is likely caused by an unknown antioxidation system restraining the fish from oxidizing. The variety of constitution of euryhaline fish, especially that of anadromous fish under spawning conditions, could result from the loss of that system. The thermal environments of heated foods are also reviewed. The basic environment of fish, which allows the formation of flavor compounds, is discussed to confirm the volatiles found in unheated fish. PMID:8744606

  15. Open and Closed Endotracheal Suctioning and Arterial Blood Gas Values: A Single-Blind Crossover Randomized Clinical Trial

    PubMed Central

    Faraji, Azam; Khatony, Alireza; Moradi, Gholamreza; Abdi, Alireza; Rezaei, Mansour

    2015-01-01

    Aim. This study was aimed at comparing the effects of the open and closed suctioning techniques on the arterial blood gas values in patients undergoing open-heart surgery. Methods. In a clinical trial, we recruited 42 patients after open-heart surgery in an educational hospital. Each patient randomly underwent both open and closed suctioning. ABGs, PaO2, SaO2, PaCO2, were analyzed before and one, five, and fifteen minutes after each suctioning episode. Results. At first the pressure of oxygen in arterial blood increased; however, this increase in the open technique was greater than that of the closed system (P < 0.001). The pressure of oxygen decreased five and fifteen minutes after both suctioning techniques (P < 0.05). The trends of carbon dioxide variations after the open and closed techniques were upward and downward, respectively. Moreover, the decrease in the level of oxygen saturation five and fifteen minutes after the open suctioning was greater than that of the closed suctioning technique (P < 0.05).  Conclusion. Arterial blood gas disturbances in the closed suctioning technique were less than those of the open technique. Therefore, to eliminate the unwanted effects of endotracheal suctioning on the arterial blood gases, the closed suctioning technique is recommended. PMID:26425366

  16. Effect of vortical structures on cavitation on impeller blades in pumps with suction chambers

    NASA Astrophysics Data System (ADS)

    Škerlavaj, A.; Pavlin, R.

    2014-03-01

    A double-suction pump operating at relatively low suction head and with poorly designed suction chambers was analysed by the computational fluid dynamics (CFD). Two impeller geometries were considered - one with thicker and one with thin layer of predicted vapour cavity on blades. Steady-state simulations (SSS) were performed with shear-stress- transport (SST) turbulence model with curvature correction (CC). Transient simulations were performed with scale-adaptive-simulation SST (SAS-SST) model with CC. For both analysed geometries, transient simulations predicted higher maximal thickness of cavities than SSS. In transient simulations it was observed that, because of poor design of suction chambers, near the rib of the suction chambers two stronger (non-cavitating) vortices appeared. Near the main vortical structures, vortices with smaller intensity appeared, with direction of rotation opposite to the main vortices. Depending on their position and direction of rotation, the vortices either decreased or increased the extent of cavitation. The most important adverse effect was to increase the size of the sheet cavity by local elongation and thickening. The local effect seemed to be more pronounced for impeller with smaller thickness of sheet cavity.

  17. Turbulent boundary layer control at moderate Reynolds numbers by means of uniform blowing/suction

    NASA Astrophysics Data System (ADS)

    Kametani, Yukinori; Fukagata, Koji; Orlu, Ramis; Schlatter, Philipp

    2015-11-01

    The effect of uniform blowing or suction from the wall on a spatially developing turbulent boundary layer has been studied in order to use them ultimately for flow control on the surface of high-speed vehicles. In the present study, a series of large eddy simulations is performed to investigate the effects of uniform blowing/suction on the skin friction drag as well as the scale of turbulent structures at moderate Reynolds numbers up to Reθ = 2500, based on free-stream velocity, U∞, and momentum thickness, θ. The amplitude of blowing or suction is fixed to 0.1% of U∞with different streamwise ranges of the control region. While the Reynolds shear and normal stresses and their spectral energy distributions are increased by blowing and decreased by suction, in particular, in the outer region, the FIK identity reveals that drag reduction (DR) or enhancement (DE) are mainly linked to changes in the spatial development of the mean wall-normal convection term rather than the contribution from the Reynolds shear stress. Despite the weak amplitude of the control, over 10% of DR and DE are achieved by blowing and suction, respectively. In case of blowing, the mean DR rate increases as the blowing region extends because the local reduction rate grows in the streamwise direction. Grant-in-Aid for Scientific Research (C) (No. 25420129), Grant-in-Aid for JSPS Fellow (No. 24-3450), the Knut an Alice Wallenberg Foundation.

  18. Numerical and Experimental Investigation of Pressure Losses at Suction of a Twin Screw Compressor

    NASA Astrophysics Data System (ADS)

    Arjeneh, M.; Kovacevic, A.; Rane, S.; Manolis, M.; Stosic, N.

    2015-08-01

    Rotary twin screw machines are used in the wide range of industrial applications and are capable of handling single and multiphase fluids as compressors, expanders and pumps. Concentration of liquid in the inlet flow can influence the performance of the machine significantly. Characteristics of the multiphase flow at the suction of a screw compressor depend on the local flow velocities and concentration. Local flow velocity measurements inside the screw compressors are difficult to obtain. However other flow properties such as local pressures are easier to attain. It is therefore useful to carry out experiments with local pressure variations in the suction which can be used to validate the 3D numerical Computational Fluid Dynamic (CFD) models that could help in studying the single and multiphase flow behaviour in screw compressors. This paper presents experimental efforts to measure the local pressure losses inside the suction plenum of the screw compressor. Pressure variations are measured at 23 locations in the suction port at various operating conditions and compared with 3D CFD model. The grid generator SCORGTM was used for generating numerical mesh of rotors. The flow calculations were carried out using commercial 3D solver ANSYS CFX. It was found that the local pressure changes predicted by the CFD model are in the good agreement with measured pressures. This validated the use of CFD for modelling of the single phase flows in suction of screw machines.

  19. Effect of Wall Suction on Cross-Flow Absolute Instability of a Rotating Disk Boundary Layer

    NASA Astrophysics Data System (ADS)

    Ho, Joanna; Corke, Thomas; Matlis, Eric

    2014-11-01

    The effect of uniform suction on the absolute instability of Type I cross-flow modes on a rotating disk is examined. Specifically it investigates if wall suction transforms the absolute instability into a global mode as postulated in the numerical simulations of Davies and Carpenter (2003). The experiment is designed so that a suction parameter of a =W0 /(νω) 1 / 2 = 0 . 2 locates the absolute instability critical Reynolds number, Rca = 650 , on the disk. Uniform wall suction is applied from R = 317 to 696. The design for wall suction follows that of Gregory and Walker (1950), where an array of holes through the disk communicate between the measurement side of the disk and the underside of the disk in an enclosure that is maintained at a slight vacuum. The measurement surface is covered by a 20 micron pore size Polyethylene sheet. Temporal disturbances are introduced using the method of Othman and Corke (2006), and the evolution of the resulting wave packets are documented. The present results indicate a rapid transition to turbulence near Rca.

  20. Performance of high-area-ratio annular dump diffuser using suction-stabilized-vortex flow control

    NASA Technical Reports Server (NTRS)

    Juhasz, A. J.; Smith, J. M.

    1977-01-01

    A short annular dump diffuser having a geometry conductive to formation of suction stabilized toroidal vortices in the region of abrupt area change was tested. The overall diffuser area ratio was 4.0 and the length to inlet height ratio was 2.0. Performance data were obtained at near ambient temperature and pressure for inlet Mach numbers of 0.18 and 0.30 with suction rates ranging from 0 to 18 percent of total inlet mass flowrate. Results show that the exit velocity profile could be readily biased toward either wall by adjustment of inner and outer wall suction rates. Symmetric exit velocity profiles were inherently unstable with a tendency to revert to a hub or tip bias. Diffuser effectiveness was increased from about 38 percent without suction to over 85 percent at a total suction rate of 10 to 12 percent. At the same time diffuser total pressure loss was reduced from 3.1 percent to 1.1 percent at an inlet Mach number of 0.3.

  1. Landiolol reduces hemodynamic responses to bronchoscopy-assisted suctioning in intubated ICU patients.

    PubMed

    Tochikubo, Junpei; Adachi, Yushi U; Ejima, Tadashi; Numaguchi, Atsushi; Matsuda, Naoyuki; Sato, Shigehito; Shiiya, Norihiko

    2014-01-01

    Landiolol is an ultra-short-acting β1-selective antagonist developed in Japan that was recently approved for the treatment of tachycardia in intensive care units (ICUs). This study investigated the protective effects of landiolol against the cardiovascular responses during bronchoscopic endotracheal suctioning. This study enrolled 15 patients requiring orotracheal intubation in an ICU. All of the patients required endotracheal suctioning using fiber bronchoscopy while sedated at a Ramsay Scale of 2-3. All subsequent suctioning procedures were assigned randomly to three groups using a cross-over design: saline as a placebo (group C) or 20 or 40 μg kg(-1) min(-1) landiolol, respectively (groups L20 and L40). The infusion was started 3 min before bronchoscopy and continued for 6 min. The central venous pressure (CVP) heart rate (HR) and arterial blood pressure (BP) were recorded. Fourteen patients completed the investigation, and 30 procedures (n = 10/group) were analyzed. The suctioning significantly increased the CVP, HR, and BP in groups C and L20, although the changes in BP were of shorter duration in group L20. No significant increase in the hemodynamic parameters was observed in group L40. The administration of landiolol 40 μg kg(-1) min(-1) prevented a harmful hyperdynamic circulatory response to bronchoscopic endotracheal suctioning, without obvious decreases in HR or BP after the intervention. PMID:25520823

  2. Suppression of the secondary flow in a suction channel of a large centrifugal pump

    NASA Astrophysics Data System (ADS)

    Torii, D.; Nagahara, T.; Okihara, T.

    2013-12-01

    The suction channel configuration of a large centrifugal pump with a 90-degree bend was studied in detail to suppress the secondary flow at the impeller inlet for improving suction performance. Design of experiments (DOE) and computational fluid dynamics (CFD) were used to evaluate the sensitivity of several primary design parameters of the suction channel. A DOE is a powerful tool to clarify the sensitivity of objective functions to design parameters with a minimum of trials. An L9 orthogonal array was adopted in this study and nine suction channels were designed, through which the flow was predicted by steady state calculation. The results indicate that a smaller bend radius with a longer straight nozzle, distributed between the bend and the impeller, suppresses the secondary flow at the impeller inlet. An optimum ratio of the cross sectional areas at the bend inlet and outlet was also confirmed in relationship to the contraction rate of the downstream straight nozzle. These findings were obtained by CFD and verified by experiments. The results will aid the design of large centrifugal pumps with better suction performance and higher reliability.

  3. A novel equation for determining the suction stress of unsaturated soils from the water retention curve based on wetted surface area in pores

    NASA Astrophysics Data System (ADS)

    Greco, Roberto; Gargano, Rudy

    2015-08-01

    A novel equation is proposed for the evaluation of the suction stress of an unsaturated soil. The equation, based on the assumption that suction is transmitted to soil solid particles only through their wet external surface, allows to easily derive the soil suction characteristic curve from the water retention curve. The proposed equation has been verified against published experimental data of suction stress smaller than 1 MPa for soils of various characteristics. In all cases, an excellent agreement between predicted and observed values of suction stress is achieved, showing that the proposed equation performs better than other currently adopted expressions for the evaluation of soil suction stress.

  4. Enhancing the performance of the domestic refrigerator with hot gas injection to suction line

    NASA Astrophysics Data System (ADS)

    Berman, E. T.; Hasan, S.; Mutaufiq

    2016-04-01

    The purpose of this study was to determine the increase in performance of a domestic refrigerator that uses hot gas injection (IHG) to the suction line. The experiment was conducted by flowing refrigerant from the discharge line to the suction line. To get performance data, measurements performed on the liquid brine as cooling load with various temperatures (range from 3°C to – 3°C). The working fluid is used as a cooling medium is R-134a. The experimental results showed that the injection of hot gas to the suction line generates an increase in the coefficient of performance systems (COPs) of 7% and is able to lower the discharge temperature, causing the compressor to work lighter/easier, saving electric power needed by the refrigerator.

  5. Performance characteristics of two annular dump diffusers using suction-stabilized vortex flow control

    NASA Technical Reports Server (NTRS)

    Juhasz, A. J.; Smith, J. M.

    1978-01-01

    The two diffusers employed in the investigation had the same overall area ratio but different prediffuser area ratios and suction slot geometries. Velocity profile and diffuser pressure recovery performance data were obtained at ambient pressure and temperature, with inlet Mach numbers ranging from 0.18 to 0.41 and suction rate varying from zero to 18% of total inlet mass flow rate. On the basis of the reported investigation it is concluded that suction stabilized vortex flow diffusers show promise for application in combustors because of relatively high static pressure recovery and low total pressure loss obtained in a short length. Performance obtained using a narrow angle (7 degree) prediffuser was superior to that obtained with a prediffuser having a 14 degree included angle.

  6. Force-Sensing Silicone Retractor for Attachment to Surgical Suction Pipes †

    PubMed Central

    Watanabe, Tetsuyou; Koyama, Toshio; Yoneyama, Takeshi; Nakada, Mitsutoshi

    2016-01-01

    This paper presents a novel force-sensing silicone retractor that can be attached to a surgical suction pipe to improve the usability of the suction and retraction functions during neurosurgery. The retractor enables simultaneous utilization of three functions: suction, retraction, and retraction-force sensing. The retractor also reduces the number of tool changes and ensures safe retraction through visualization of the magnitude of the retraction force. The proposed force-sensing system is based on a force visualization mechanism through which the force is displayed in the form of motion of a colored pole. This enables surgeons to estimate the retraction force. When a fiberscope or camera is present, the retractor enables measurement of the retraction force with a resolution of 0.05 N. The retractor has advantages of being disposable, inexpensive, and easy to sterilize or disinfect. Finite element analysis and experiments demonstrate the validity of the proposed force-sensing system. PMID:27455258

  7. Effects of wall suction/blowing on two-dimensional flow past a confined square cylinder.

    PubMed

    Zhang, Wei; Jiang, Yanqun; Li, Lang; Chen, Guoping

    2016-01-01

    A numerical simulation is conducted to study the laminar flow past a square cylinder confined in a channel (the ratio of side length of the square to channel width is fixed at 1/4) subjected to a locally uniform blowing/suction speed placed at the top and bottom channel walls. Governing equations with boundary conditions are resolved using a finite volume method in pressure-velocity formulation. The flow patterns relevant to the critical spacing values are investigated. Numerical results show that wall blowing has a stabilizing effect on the flow, and the corresponding critical Reynolds number increases monotonically with increasing blowing velocity. Remarkably, steady asymmetric solutions and hysteretic mode transitions exist in a certain range of parameters (Reynolds number and suction speed) in the case of suction. PMID:27462481

  8. Functional morphology of suction discs and attachment performance of the Mediterranean medicinal leech (Hirudo verbana Carena).

    PubMed

    Kampowski, Tim; Eberhard, Laura; Gallenmüller, Friederike; Speck, Thomas; Poppinga, Simon

    2016-04-01

    Medicinal leeches use their suction discs for locomotion, adhesion to the host and, in the case of the anterior disc, also for blood ingestion. The biomechanics of their suction-based adhesion systems has been little understood until now. We investigated the functional morphology of the anterior and posterior suckers ofHirudo verbanaby using light and scanning electron microscopy. Furthermore, we analysed the adhesion qualitatively and quantitatively by conducting behavioural and mechanical experiments. Our high-speed video analyses provide new insights into the attachment and detachment processes and we present a detailed description of the leech locomotion cycle. Pull-off force measurements of the anterior and posterior suction organs on seven different substrates under both aerial and water-submersed conditions reveal a significant influence of the surrounding medium, the substrate surface roughness and the tested organ on attachment forces and tenacities. PMID:27075001

  9. Force-Sensing Silicone Retractor for Attachment to Surgical Suction Pipes.

    PubMed

    Watanabe, Tetsuyou; Koyama, Toshio; Yoneyama, Takeshi; Nakada, Mitsutoshi

    2016-01-01

    This paper presents a novel force-sensing silicone retractor that can be attached to a surgical suction pipe to improve the usability of the suction and retraction functions during neurosurgery. The retractor enables simultaneous utilization of three functions: suction, retraction, and retraction-force sensing. The retractor also reduces the number of tool changes and ensures safe retraction through visualization of the magnitude of the retraction force. The proposed force-sensing system is based on a force visualization mechanism through which the force is displayed in the form of motion of a colored pole. This enables surgeons to estimate the retraction force. When a fiberscope or camera is present, the retractor enables measurement of the retraction force with a resolution of 0.05 N. The retractor has advantages of being disposable, inexpensive, and easy to sterilize or disinfect. Finite element analysis and experiments demonstrate the validity of the proposed force-sensing system. PMID:27455258

  10. The effect of open and closed endotracheal tube suctioning system on respiratory parameters of infants undergoing mechanical ventilation

    PubMed Central

    Taheri, Parvin; Asgari, Narges; Mohammadizadeh, Majid; Golchin, Mehri

    2012-01-01

    Aims: Mechanical ventilation is used for some infants in neonatal intensive care units (NICU) due to many physiological and clinical causes. Since these patients have endotracheal tubes, cleaning and keeping the airways open through suctioning should be done to increase oxygenation. This study aimed to evaluate effect of open and closed suctioning methods on respiratory parameters of infants undergoing mechanical ventilation. Materials and Methods: In this crossover clinical trial, 44 infants were selected among those undergone mechanical ventilation in NICU of Isfahan's Al-Zahra Hospital using convenience sampling method. The subjects were randomly divided into two groups. In the first group, open suctioning was carried out and after three hours of cleaning, closed suctioning was done. In the second group, closed suctioning was firstly done and following three hours of cleaning, open suctioning was implemented. Respiratory rate (RR) and percentage of arterial blood oxygen saturation was measured before, during and after each type of suctioning. Data were analyzed using repeated measures ANOVA and independent student's t-test. Findings: There was a significant difference between mean respiratory rate and arterial blood oxygen saturation in infants before, during and after the closed and open suctioning. The percentage of arterial blood oxygen saturation had a significant reduction in open method compared to closed method during suctioning and immediately after it. RR three minutes after suctioning showed a significant reduction in both steps in open method compared to closed method. Conclusions: Close method caused fewer changes in hemodynamic status of infants. Therefore, in order to prevent respiratory complications in infants, nurses are recommended to perform the endotracheal tube suctioning by closed method. PMID:23493041

  11. High-Intensity Focused Ultrasound Combined With Suction Curettage for the Treatment of Cesarean Scar Pregnancy

    PubMed Central

    Zhu, Xiaogang; Deng, Xinliang; Wan, Yajun; Xiao, Songshu; Huang, Jiping; Zhang, Lian; Xue, Min

    2015-01-01

    Abstract The aim of this study was to retrospectively evaluate the safety and feasibility of high-intensity focused ultrasound (HIFU) treatment combined with suction curettage under hysteroscopic guidance for cesarean scar pregnancy (CSP). Fifty-three patients with definite CSP were treated with HIFU followed by suction curettage under hysteroscopic guidance. All the patients received 1 session of HIFU ablation under conscious sedation. Suction curettage under hysteroscopic guidance was performed at an average of 2.9 (range: 1–5) days after HIFU ablation. Blood flow of pregnancy tissue before and after HIFU, intraoperative blood loss in suction curettage and hysteroscopy procedure, time for β-human chorionic gonadotropin (β-hCG) to return to normal level, and time for normal menstruation recovery were recorded. Immediately after HIFU treatment, color Doppler ultrasound showed that the fetal cardiac activity disappeared and the blood flow in the pregnancy tissue significantly decreased. All the patients underwent suction curettage under hysteroscopic guidance after the treatment of HIFU, the median volume of blood loss in the procedure was 20 mL (range: 10–400 mL). The average time for menstruation recovery was 35.1 ± 8.1 (range: 19–60) days. The average time needed for serum β-hCG to return to normal levels was 27.5 ± 6.4 (range: 12–40) days. The average hospital stay was 7.8 ± 1.5 (range: 5–11) days. Based on our results, it appears that HIFU combined with suction curettage under hysteroscopic guidance is safe and effective in treating patients with CSP at gestational ages <8 weeks. PMID:25950698

  12. Microarray-based gene expression profiles in rabbit retina due to negative pressure suction.

    PubMed

    Zhao, H X; Niu, C M; Guan, W Y

    2012-01-01

    We investigated a possible molecular pathogenesis involving retinal ganglion cell apoptosis following transient high intraocular pressure. Changes in the gene expression profiles of the retina were detected via gene chip methodology. Twelve New Zealand white rabbits were randomly assigned to control and 3-min negative pressure suction groups. The control group was treated only with a laser, and the experimental group was also treated with suction for 3 min, using a negative pressure generator. Total RNA was then extracted from the retinal tissue at different recovery stages to analyze gene expression profiles using the Agilent rabbit one-way gene chip. The groups were then compared. Immediately after negative pressure suction induction, 704 genes were differentially expressed. Among these, 485 genes were upregulated, and 219 were downregulated. Expression of the genes encoding CRYAA, CRYAB, and TLR3 genes, which are involved in apoptosis, was elevated. The KRT18 gene, which is involved in apoptosis, had reduced expression. Seven days after negative pressure suction, 482 genes were differentially expressed. Among these, 178 genes were upregulated, and 304 were downregulated. Expression of the genes encoding CRYAB, IL1-BETA and IL1R1, which are involved in apoptosis, was upregulated. Ten days after negative pressure suction, 402 genes were differentially expressed. Of these, 213 genes were upregulated, and 189 were downregulated. Apoptosis genes CRYAB, CRYBA3, CRYBB2, IL1- BETA, and IL1R1 showed higher expression levels. We concluded that negative pressure suction for long periods of time (for example, 3 min) results in changes in gene expression. Genes with higher fold changes help protect retinal ganglion cells from apoptosis. We suggest that promoting the expression of these genes should be considered as a new means for treating ischemic-hypoxic retinopathy. PMID:22653643

  13. High-intensity focused ultrasound combined with suction curettage for the treatment of cesarean scar pregnancy.

    PubMed

    Zhu, Xiaogang; Deng, Xinliang; Wan, Yajun; Xiao, Songshu; Huang, Jiping; Zhang, Lian; Xue, Min

    2015-05-01

    The aim of this study was to retrospectively evaluate the safety and feasibility of high-intensity focused ultrasound (HIFU) treatment combined with suction curettage under hysteroscopic guidance for cesarean scar pregnancy (CSP).Fifty-three patients with definite CSP were treated with HIFU followed by suction curettage under hysteroscopic guidance. All the patients received 1 session of HIFU ablation under conscious sedation. Suction curettage under hysteroscopic guidance was performed at an average of 2.9 (range: 1-5) days after HIFU ablation. Blood flow of pregnancy tissue before and after HIFU, intraoperative blood loss in suction curettage and hysteroscopy procedure, time for β-human chorionic gonadotropin (β-hCG) to return to normal level, and time for normal menstruation recovery were recorded.Immediately after HIFU treatment, color Doppler ultrasound showed that the fetal cardiac activity disappeared and the blood flow in the pregnancy tissue significantly decreased. All the patients underwent suction curettage under hysteroscopic guidance after the treatment of HIFU, the median volume of blood loss in the procedure was 20 mL (range: 10-400 mL). The average time for menstruation recovery was 35.1 ± 8.1 (range: 19-60) days. The average time needed for serum β-hCG to return to normal levels was 27.5 ± 6.4 (range: 12-40) days. The average hospital stay was 7.8 ± 1.5 (range: 5-11) days.Based on our results, it appears that HIFU combined with suction curettage under hysteroscopic guidance is safe and effective in treating patients with CSP at gestational ages <8 weeks. PMID:25950698

  14. Conservation and variation in the feeding mechanism of the spiny dogfish squalus acanthias

    PubMed

    Wilga; Motta

    1998-05-01

    Changes in the feeding mechanism with feeding behavior were investigated using high-speed video and electromyography to examine the kinematics and motor pattern of prey capture, manipulation and transport in the spiny dogfish Squalus acanthias (Squalidae: Squaliformes). In this study, Squalus acanthias used both suction and ram behaviors to capture and manipulate prey, while only suction was used to transport prey. The basic kinematic feeding sequence observed in other aquatic-feeding lower vertebrates is conserved in the spiny dogfish. Prey capture, bite manipulation and suction transport events are characterized by a common pattern of head movements and motor activity, but are distinguishable by differences in duration and relative timing. In general, capture events are longer in duration than manipulation and transport events, as found in other aquatic-feeding lower vertebrates. Numerous individual effects were found, indicating that individual sharks are capable of varying head movements and motor activity among successful feeding events. Upper jaw protrusion in the spiny dogfish is not restricted by its orbitostylic jaw suspension; rather, the upper jaw is protruded by 30 % of its head length, considerably more than in the lemon shark Negaprion brevirostris (Carcharhinidae: Carcharhiniformes) (18 %) with its hyostylic jaw suspension. One function of upper jaw protrusion is to assist in jaw closure by protruding the upper jaw as well as elevating the lower jaw to close the gape, thus decreasing the time to jaw closure. The mechanism of upper jaw protrusion was found to differ between squaliform and carcharhiniform sharks. Whereas the levator palatoquadrati muscle assists in retracting the upper jaw in the spiny dogfish, it assists in protruding the upper jaw in the lemon shark. This study represents the first comprehensive electromyographic and kinematic analysis of the feeding mechanism in a squaliform shark. PMID:9547315

  15. STAYLAM: A FORTRAN program for the suction transition analysis of a yawed wing laminar boundary layer

    NASA Technical Reports Server (NTRS)

    Carter, J. E.

    1977-01-01

    A computer program called STAYLAM is presented for the computation of the compressible laminar boundary-layer flow over a yawed infinite wing including distributed suction. This program is restricted to the transonic speed range or less due to the approximate treatment of the compressibility effects. The prescribed suction distribution is permitted to change discontinuously along the chord measured perpendicular to the wing leading edge. Estimates of transition are made by considering leading edge contamination, cross flow instability, and instability of the Tollmien-Schlichting type. A program listing is given in addition to user instructions and a sample case.

  16. Surgical treatment of axillary hyperhidrosis by suction-curettage of sweat glands*

    PubMed Central

    de Rezende, Rebeca Maffra; Luz, Flávio Barbosa

    2014-01-01

    Suction curettage is a dermatologic surgery technique for the treatment of axillary hyperhidrosis, which is becoming more popular. Objective: The purpose of this study is to describe the current technique of removal of axillary sweat glands, and evaluate its efficacy and safety. Conclusion: Suction-curettage of sweat glands is a minimally invasive surgical technique that is easy to perform, safe, has high rates of success and relatively few side-effects. It is generally well tolerated by patients and requires shorter time away from daily activities, when compared with other surgical modalities. PMID:25387499

  17. Effect of Suction on Controlling the Secondary Instability of Boundary Layers

    NASA Technical Reports Server (NTRS)

    El-Hady, Nabil M.

    1990-01-01

    The effect of suction on controlling the 3-D secondary instability is investigated for a boundary layer with pressure gradient in the presence of small but finite amplitude Tollmien-Schlichting wave. The focus is on principal parametric resonance responsible for strong growth of subharmonics in low disturbance environment. Calculations are presented for the effect of suction on the onset and amplification of the secondary instability in Blasius and Falkner-Skan flows, as well as its effect on controlling the production of the vortical structure.

  18. A modified Guedel airway for continuous oxygenation and suctioning during fibreoptic bronchoscopy.

    PubMed

    Ayoub, C; Itani, M M; Lteif, A; Baraka, A

    2000-05-01

    We describe a modification to the Guedel airway that improves suction and oxygenation during fibreoptic bronchoscopy. The entire roof of a Guedel airway was removed. Two 2.5-mm internal diameter tracheal tubes were inserted into the modified airway to allow continuous oxygen delivery and suction throughout fibreoptic bronchoscopy. It was tested as a single-use device in ten patients undergoing awake fibreoptic bronchoscopy under sedation and topical anasthesia. During the procedure there were no problems with either fogging of the lens or secretions in the pharynx. In addition, oxyhaemoglobin saturation, as monitored continuously by pulse oximetry, was >/= 97% in all patients. PMID:10792137

  19. Effect of suction on controlling the secondary instability of boundary layers

    NASA Technical Reports Server (NTRS)

    El-Hady, Nabil M.

    1991-01-01

    The effect of suction on controlling the three-dimensional secondary instability is investigated for a boundary layer with a pressure gradient in the presence of a small but finite-amplitude Tollmien-Schlichting wave. The focus is on the principal parametric resonance responsible for the strong growth of subharmonics in a low disturbance environment. Calculations are presented for the effect of suction on the onset and amplification of the secondary instability in Blasius and Falkner-Skan flows, as well as its effect on controlling the production of the vortical structure.

  20. Some recent applications of the suction analogy to vortex-lift estimates

    NASA Technical Reports Server (NTRS)

    Lamar, J. E.

    1976-01-01

    An extension of the suction analogy for the estimation of vortex lift along the side edge of wings is reviewed along with the concept of an augmented vortex lift to account for the effect of the leading-edge vortex passing downstream over an aft part of the model. Applications of these extensions have resulted in an improved estimating capability for a wide range of isolated sharp-edge planforms and also for multiple lifting surfaces. Hence, the suction analogy concept can now have wider applicability at both subsonic and supersonic speeds, especially in the preliminary design cycle.

  1. The design and performance of axially symmetrical contoured wall diffusers employing suction boundary layer control

    NASA Technical Reports Server (NTRS)

    Nelson, C. D., Jr.; Hudson, W. G.; Yang, T.

    1974-01-01

    This paper presents a procedure for the design and the performance prediction of axially symmetrical contoured wall diffusers employing suction boundary layer control. An inverse problem approach was used in the potential flow design of the diffuser wall contours. The experimentally observed flow characteristics and the stability of flows within the diffuser are also described. Guidelines for the design of low suction (less than 10 percent of the inlet flow) and thus high effectiveness contoured wall diffusers are also provided based on the results of the experimental program.

  2. Texture Fish

    ERIC Educational Resources Information Center

    Stone, Julie

    2007-01-01

    In an effort to provide an opportunity for her first graders to explore texture through an engaging subject, the author developed a three-part lesson that features fish in a mixed-media artwork: (1) Exploring Textured Paint; (2) Creating the Fish; and (3) Role Playing. In this lesson, students effectively explore texture through painting, drawing,…

  3. Effects of prolonged mechanical ventilation with a closed suction system on endotracheal tube resistance and its reversibility by a closed suction cleaning system.

    PubMed

    Adi, N A; Tomer, N T; Bergman, G B; Kishinevsky, E K; Wyncoll, D W

    2013-11-01

    The study objective was to evaluate endotracheal tubes (ETT) from extubated adult patients and compare them to new, unused, size-matched control tubes for changes in inspiratory resistance (Rinsp) and peak inspiratory pressure (PIP) before and immediately after suctioning with the Airway Medix Closed Suction System (AMCSS) (Biovo Technologies, 2013 Tel Aviv, Israel). Sixteen ETTs were recovered from predominantly medical patients who had required intubation and mechanical ventilation for more than 12 hours. ETTs were evaluated within 4.5 hours of extubation. Readings were taken during square wave flow, at rates of 40 and 60 l/minute. Cleaning of extubated ETTs using the AMCSS was able to restore them to almost original conditions in terms of Rinsp and PIP. The examined ETTs included tubes of various sizes ranging from internal diameter (ID) 7 to 8.5 mm and intubation periods ranging from 12 hours to 21 days. The mean Rinsp for the used and uncleaned ETTs was equivalent to 275% of the Rinsp of sized-matched new and unused ETTs. For 8 mm ID ETTs this was comparable to a measured Rinsp of a 5 mm tube. Following a single cleaning episode with the AMCSS, Rinsp decreased, regaining an effective ETT ID of a 7.5 to 8 mm tube. A single suctioning episode with this device resulted in a significant reduction in Rinsp, virtually restoring original flow variable values. The AMCSS represents a novel technology in closed suction systems, designed to achieve more effective inner lumen cleaning in prolonged mechanical ventilation. PMID:24180713

  4. The use of marine products in animal feeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal feeds represent a growing market for the nutrient rich by-products of marine fish and seafood processing. Fishmeal is one product obtained from fisheries that was traditionally used as a low-cost source of protein to supplement pig and poultry feeds. Fishmeal typically contains over 50 wt% cr...

  5. Independently evolved upper jaw protrusion mechanisms show convergent hydrodynamic function in teleost fishes.

    PubMed

    Staab, Katie Lynn; Holzman, Roi; Hernandez, L Patricia; Wainwright, Peter C

    2012-05-01

    A protrusible upper jaw has independently evolved multiple times within teleosts and has been implicated in the success of two groups in particular: Acanthomorpha and Cypriniformes. We use digital particle image velocimetry (DPIV) to compare suction feeding flow dynamics in a representative of each of these clades: goldfish and bluegill. Using DPIV, we contrast the spatial pattern of flow, the temporal relationship between flow and head kinematics, and the contribution of jaw protrusion to the forces exerted on prey. As expected, the spatial patterns of flow were similar in the two species. However, goldfish were slower to reach maximal kinematic excursions, and were more flexible in the relative timing of jaw protrusion, other jaw movements and suction flows. Goldfish were also able to sustain flow speeds for a prolonged period of time as compared with bluegill, in part because goldfish generate lower peak flow speeds. In both species, jaw protrusion increased the force exerted on the prey. However, slower jaw protrusion in goldfish resulted in less augmentation of suction forces. This difference in force exerted on prey corresponds with differences in trophic niches and feeding behavior of the two species. The bluegill uses powerful suction to capture insect larvae whereas the goldfish uses winnowing to sort through detritus and sediment. The kinethmoid of goldfish may permit jaw protrusion that is independent of lower jaw movement, which could explain the ability of goldfish to decouple suction flows (due to buccal expansion) from upper jaw protrusion. Nevertheless, our results show that jaw protrusion allows both species to augment the force exerted on prey, suggesting that this is a fundamental benefit of jaw protrusion to suction feeders. PMID:22496281

  6. Fishing effects on energy use by North Sea fishes

    NASA Astrophysics Data System (ADS)

    Jennings, Simon; van Hal, Ralf; Hiddink, Jan G.; Maxwell, Tracy A. D.

    Fishing affects patterns of energy use in fish populations, as demonstrated by changes in population energy consumption and the size and age when energy demands are greatest. We compare theoretical predictions and observed patterns of energy use (expressed as the primary production required to support fish production) by North Sea fish, based on simple and widely applicable theory that links life history parameters, fishing mortality ( F), trophic transfer efficiency and relationships between size and trophic level (as determined using nitrogen stable isotope analysis). For the demersal species that dominate total biomass, relationships between size and trophic level were quite consistent among years. There were large decreases in relative energy requirements of all exploited demersal populations except plaice Pleuronectes platessa during the last 3 to 4 decades. Relative energy requirements of plaice were more stable because smaller plaice, which now dominate the exploited population, feed at higher trophic levels than larger plaice. The sizes and ages when population energy demands were greatest fell with increasing fishing mortality and differences between the predicted ( F = 0) and observed ages at maximum energy demand were greater in larger species. Currently, the energy demands of most species peak early in life (1-3 years) and largely reflect patterns of recruitment, leading to a homogenisation of the trophodynamics of the fish community. The fate of energy that is no longer used by commercially exploited species is not clear, partly because of the infrequent and untargeted monitoring of species that are more resilient to fishing. However, we conducted a preliminary assessment of the energy demands of solenette Buglossidium luteum, a very abundant small flatfish in the central North Sea that has increased in abundance in recent years. The solenette's high abundance and resilience to fishing, suggests that it now requires 35% of primary production in part of

  7. Effects of Dietary Protein Concentration and Feeding Regimen on Channel Catfish Ictalurus punctatus Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A factorial experiment was conducted to examine effects of dietary protein concentration (24, 28, 32, or 36%) and feeding regimen (feeding once daily or every other d) on channel catfish Ictalurus punctatus production in earthen ponds. Compared with fish fed daily, fish fed every other d had lower ...

  8. 21 CFR 878.4683 - Non-Powered suction apparatus device intended for negative pressure wound therapy.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... negative pressure wound therapy. 878.4683 Section 878.4683 Food and Drugs FOOD AND DRUG ADMINISTRATION... Surgical Devices § 878.4683 Non-Powered suction apparatus device intended for negative pressure wound therapy. (a) Identification. A non-powered suction apparatus device intended for negative pressure...

  9. 21 CFR 878.4683 - Non-Powered suction apparatus device intended for negative pressure wound therapy.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... negative pressure wound therapy. 878.4683 Section 878.4683 Food and Drugs FOOD AND DRUG ADMINISTRATION... Surgical Devices § 878.4683 Non-Powered suction apparatus device intended for negative pressure wound therapy. (a) Identification. A non-powered suction apparatus device intended for negative pressure...

  10. 21 CFR 878.4683 - Non-Powered suction apparatus device intended for negative pressure wound therapy.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... negative pressure wound therapy. 878.4683 Section 878.4683 Food and Drugs FOOD AND DRUG ADMINISTRATION... Surgical Devices § 878.4683 Non-Powered suction apparatus device intended for negative pressure wound therapy. (a) Identification. A non-powered suction apparatus device intended for negative pressure...

  11. 21 CFR 878.4683 - Non-Powered suction apparatus device intended for negative pressure wound therapy.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... negative pressure wound therapy. 878.4683 Section 878.4683 Food and Drugs FOOD AND DRUG ADMINISTRATION... Surgical Devices § 878.4683 Non-Powered suction apparatus device intended for negative pressure wound therapy. (a) Identification. A non-powered suction apparatus device intended for negative pressure...

  12. An Approximate Method for Calculation of the Laminar Boundary Layer with Suction for Bodies of Arbitrary Shape

    NASA Technical Reports Server (NTRS)

    Schlichting, H.

    1949-01-01

    Various ways were tried recently to decrease the friction drag of a body in a flow; they all employ influencing the boundary layer. One of them consists in keeping the boundary layer Laminar by suction; promising tests have been carried out. Since for large Reynolds numbers the friction drag of the laminar boundary layer is much lower than that of the turbulent boundary layer, a considerable saving in drag results from keeping the boundary layer laminar, even with the blower power required for suction taken into account. The boundary layer is kept laminar by suction in two ways: first, by reduction of the thickness of the boundary layer and second, by the fact that the suction changes the form of the velocity distribution so that it becomes more stable, in a manner similar to the change by a pressure drop. There by the critical Reynolds number of the boundary layer (USigma*/V) (sub crit) becomes considerably higher than for the case without suction. This latter circumstance takes full effect only if continuous suction is applied which one might visualize realized through a porous wall. Thus the suction quantities required for keeping the boundary layer laminar become so small that the suction must be regarded as a very promising auxiliary means for drag reduction.

  13. Effects of no feeding, maintenance feeding, and refeeding on production and processing characteristics of market-size hybrid catfish

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A pond study was initiated to evaluate effects of no feeding, maintenance feeding, and refeeding on production and processing characteristics of market-size hybrid catfish (female Channel Catfish Ictalurus punctatus × male Blue Catfish I. furcatus). Fish with an average weight of 644 g were stocked ...

  14. Instabilities orginating from suction holes used for Laminar Flow Control (LFC)

    NASA Technical Reports Server (NTRS)

    Watmuff, Jonathan H.

    1994-01-01

    A small-scale wind tunnel previously used for turbulent boundary layer studies has been modified for experiments in laminar flow control. The facility incorporates suction through interchangeable porous test surfaces which are used to stabilize the boundary layer and delay transition to turbulent flow. The thin porous test surfaces are supported by a baffled plenum chamber box which also acts to gather the flow through the surface into tubes which are routed to a high pressure fan. An elliptic leading edge is attached to the assembly to establish a new layer on the test plate. A slot is used to remove the test section flow below the leading edge. The test section was lengthened and fitted with a new ceiling. Substantial modifications were also made to the 3D probe traverse. Detailed studies have been made using isolated holes to explore the underlying instability mechanisms. The suction is perturbed harmonically and data are averaged on the basis of the phase of the disturbance. Conditions corresponding to strong suction and without suction have been studied. In both cases, 3D contour surfaces in the vicinity of the hole show highly three-dimensional T-S waves that fan out away from the hole with streamwise distance. With suction, the perturbations on the centerline are much stronger and decay less rapidly, while the far field is similar to the case without suction. Downstream the contour surfaces of the bow-shaped TS waves develop spanwise irregularities which eventually form into clumps. The contours remain smooth when suction is not applied. Even without suction, the harmonic point source is challenging for CFD; e.g. DNS has been used for streamwise growth. With suction, grid resources are consumed by the hole and this makes DNS even more expensive. Limited DNS results so far indicate that the vortices which emanate from suction holes appear to be stable. The spanwise clumping observed in the experiment is evidence of a secondary instability that could be

  15. The Fish may be Used in the Space System

    NASA Astrophysics Data System (ADS)

    Liu, Chungchu; Liu, Xiaofeng; Lin, Zhongning

    Scientists in Space area like to grow fish in the biosphere, but they worry about that fish will contest oxygen with humans. Therefore growing low-oxygen-needing fish is very important. After research, we found a fish which may be a promising fish used in space system. This fish can grow normally under 1mg O2/1000 mg water oxygen condition while other species of fish die away. How to keep astronauts healthy and having delicious food are problem to raise life qualities of astronauts in space. Our pharmacological test shows that this chosen fish, with high DHA and EPA, in general, other fresh-water fish has low DHA and EPA. It has functions of anti-radiation and anti-tumor. It can also prolong cruor time, anoxia-tolerating, and swimming time after the mice feeding with the fish's meat.

  16. Survival of vaccinated, feed-trained largemouth bass fry (Micropterus salmoides floridanus) during natural exposure to Flavobacterium columnare

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccinated, feed-trained largemouth bass fry (Micropterus salmoides floridanus) were cohabited with sham-vaccinated fish. Fish were exposed, under natural conditions, to Flavobacterium columnare, a ubiquitous bacterium associated with columnaris disease. During every time interval, the probability...

  17. High Reynolds Number Hybrid Laminar Flow Control (HLFC) Flight Experiment. Report 4; Suction System Design and Manufacture

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This document describes the design of the leading edge suction system for flight demonstration of hybrid laminar flow control on the Boeing 757 airplane. The exterior pressures on the wing surface and the required suction quantity and distribution were determined in previous work. A system consisting of porous skin, sub-surface spanwise passages ("flutes"), pressure regulating screens and valves, collection fittings, ducts and a turbocompressor was defined to provide the required suction flow. Provisions were also made for flexible control of suction distribution and quantity for HLFC research purposes. Analysis methods for determining pressure drops and flow for transpiration heating for thermal anti-icing are defined. The control scheme used to observe and modulate suction distribution in flight is described.

  18. Topology optimization of a suction muffler in a fluid machine to maximize energy efficiency and minimize broadband noise

    NASA Astrophysics Data System (ADS)

    Oh, Seungjae; Wang, Semyung; Cho, Sungman

    2016-03-01

    A suction muffler used in a fluid machine has three functions: noise reduction; minimizing pressure drop and improving energy efficiency using acoustic effects. However, no method of suction muffler design considers all three of these functions concurrently. Therefore, in this study, we attempt to provide an integrated design method of a suction muffler in a fluid machine that considers all three functions. The topology optimization method for acoustic and fluid systems was applied to an integrated design. However, the interaction between fluid and acoustic was not considered. In addition, the acoustic input impedance of a suction muffler was used for a specific acoustical resonance frequency to improve the energy efficiency of a fluid machine. Finally, the sequential optimization method based on physical investigations was proposed to satisfy several design criteria. The proposed method was applied to the suction muffler in refrigerator's compressor.

  19. Nasogastric feeding tube

    MedlinePlus

    Feeding - nasogastric tube; NG tube; Bolus feeding; Continuous pump feeding; Gavage tube ... A nasogastric tube (NG tube) is a special tube that carries food and medicine to the stomach through the nose. It can be ...

  20. Effects of winter feeding on growth, body composition, and processing traits of co-cultured blue catfish, channel catfish, and channel catfish x blue catfish hybrids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many catfish farmers do not feed or feed fish very infrequently during the winter months because feeding activity is reduced at cold water temperatures. However, studies have demonstrated that winter feeding can improve catfish weight gain and processing yield relative to not feeding. We compared ...

  1. An Ultrathin Endoscope with a 2.4-mm Working Channel Shortens the Esophagogastroduodenoscopy Time by Shortening the Suction Time

    PubMed Central

    Shinozaki, Satoshi; Miura, Yoshimasa; Ino, Yuji; Shinozaki, Kenjiro; Lefor, Alan Kawarai; Yamamoto, Hironori

    2015-01-01

    Background/Aims: Poor suction ability through a narrow working channel prolongs esophagogastroduodenoscopy (EGD). The aim of this study was to evaluate suction with a new ultrathin endoscope (EG-580NW2; Fujifilm Corp.) having a 2.4-mm working channel in clinical practice. Methods: To evaluate in vitro suction, 200 mL water was suctioned and the suction time was measured. The clinical data of 117 patients who underwent EGD were retrospectively reviewed on the basis of recorded video, and the suction time was measured by using a stopwatch. Results: In vitro, the suction time with the EG-580NW2 endoscope was significantly shorter than that with the use of an ultrathin endoscope with a 2.0-mm working channel (EG-580NW; mean ± standard deviation, 22.7±1.1 seconds vs. 34.7±2.2 seconds; p<0.001). We analyzed the total time and the suction time for routine EGD in 117 patients (50 in the EG-580NW2 group and 67 in the EG-580NW group). In the EG-580NW2 group, the total time for EGD was significantly shorter than that in the EG-580NW group (275.3±42.0 seconds vs. 300.6±46.5 seconds, p=0.003). In the EG-580NW2 group, the suction time was significantly shorter than that in the EG-580NW group (19.2±7.6 seconds vs. 38.0±15.9 seconds, p<0.001). Conclusions: An ultrathin endoscope with a 2.4-mm working channel considerably shortens the routine EGD time by shortening the suction time, in comparison with an endoscope with a 2.0-mm working channel. PMID:26668798

  2. One Fish, Two Fish, Redfish, You Fish!

    ERIC Educational Resources Information Center

    White, Katherine; Timmons, Maryellen; Medders, Paul

    2011-01-01

    The recreational fishing activity presented in this article provides a hands-on, problem-based experience for students; it unites biology, math, economics, environmental policy, and population dynamics concepts. In addition, the activity allows students to shape environmental policy in a realistic setting and evaluate their peers' work. By…

  3. Fishing Forecasts

    NASA Technical Reports Server (NTRS)

    1988-01-01

    ROFFS stands for Roffer's Ocean Fishing Forecasting Service, Inc. Roffer combines satellite and computer technology with oceanographic information from several sources to produce frequently updated charts sometimes as often as 30 times a day showing clues to the location of marlin, sailfish, tuna, swordfish and a variety of other types. Also provides customized forecasts for racing boats and the shipping industry along with seasonal forecasts that allow the marine industry to formulate fishing strategies based on foreknowledge of the arrival and departure times of different fish. Roffs service exemplifies the potential for benefits to marine industries from satellite observations. Most notable results are reduced search time and substantial fuel savings.

  4. Feeding a future world.

    PubMed

    Hinrichsen, D

    1998-01-01

    This article provides an overview of future prospects for feeding the world's growing population. The discussion focuses on obstacles such as limited agricultural land, degraded soil and water, and water shortages. The evidence suggests that sustainability is declining, especially in poor, food-deficit countries with growing populations. The world is segregated into the haves, the poor have-nots, and the rich have-nots. North America, Europe, and Australia have enough cropland to feed their populations. The poor have-nots are located mostly in sub-Saharan Africa, 7 countries each in the Middle East and Latin America, 6 in Oceania, and the rest in Central and South Asia. The poor have-nots amount to 3 billion out of 6 billion total population. The rich have-nots include countries such as Japan and Singapore, plus China, Indonesia, Peru, Chile, and Saudi Arabia and other Gulf states. The rich have-nots must import food. The world grain harvest is no longer tripling. Per person yields have declined. Increasing food productivity must rely on existing lands. The size of family farms has declined. Almost 2 billion hectares of crop and grazing land is degraded. Yields from irrigated land that are 33% of world food supply have declined. In 1990, 28 countries with 335 million people faced chronic water shortages or scarcity. Water is being polluted. Fish stocks are being depleted. Genetic diversity is being lost. In 182 food deficit countries, population growth must be slowed, and agriculture must be sustainable. Food is neither produced nor consumed equitably. Malnutrition is caused by poverty. Food security cannot be achieved if land and water become increasingly degraded or lost. PMID:12348766

  5. Performance and scaling of a novel locomotor structure: adhesive capacity of climbing gobiid fishes.

    PubMed

    Maie, Takashi; Schoenfuss, Heiko L; Blob, Richard W

    2012-11-15

    Many species of gobiid fishes adhere to surfaces using a sucker formed from fusion of the pelvic fins. Juveniles of many amphidromous species use this pelvic sucker to scale waterfalls during migrations to upstream habitats after an oceanic larval phase. However, adults may still use suckers to re-scale waterfalls if displaced. If attachment force is proportional to sucker area and if growth of the sucker is isometric, then increases in the forces that climbing fish must resist might outpace adhesive capacity, causing climbing performance to decline through ontogeny. To test for such trends, we measured pressure differentials and adhesive suction forces generated by the pelvic sucker across wide size ranges in six goby species, including climbing and non-climbing taxa. Suction was achieved via two distinct growth strategies: (1) small suckers with isometric (or negatively allometric) scaling among climbing gobies and (2) large suckers with positively allometric growth in non-climbing gobies. Species using the first strategy show a high baseline of adhesive capacity that may aid climbing performance throughout ontogeny, with pressure differentials and suction forces much greater than expected if adhesion were a passive function of sucker area. In contrast, large suckers possessed by non-climbing species may help compensate for reduced pressure differentials, thereby producing suction sufficient to support body weight. Climbing Sicyopterus species also use oral suckers during climbing waterfalls, and these exhibited scaling patterns similar to those for pelvic suckers. However, oral suction force was considerably lower than that for pelvic suckers, reducing the ability for these fish to attach to substrates by the oral sucker alone. PMID:23100486

  6. Fishing Long-Fingered Bats (Myotis capaccinii) Prey Regularly upon Exotic Fish

    PubMed Central

    Aizpurua, Ostaizka; Garin, Inazio; Alberdi, Antton; Salsamendi, Egoitz; Baagøe, Hans; Aihartza, Joxerra

    2013-01-01

    The long-fingered bat Myotis capaccinii is a European trawling bat reported to feed on fish in several Mediterranean locations, but the ecological circumstances of this behavior have not yet been studied. To elucidate the importance of fishing in this bat's diet, we evaluated the frequency and seasonal variation of fish remains in 3,000 fecal pellets collected from M. capaccinii at a nursery roost in Dénia (Eastern Iberian Peninsula) in 2008, 2009, and 2010. Fish consumption occurred evenly throughout the year. All otoliths found in feces were identified as belonging to the surface-feeding fish Gambusia holbrooki. Measuring otoliths, we estimated that the mean size of consumed fish was significantly smaller than the mean measured for available fish, suggesting that the long-fingered bat's relatively small body may constrain its handling of larger prey. Of note, one bat had eaten 15 fish, showing that fish may be a locally or seasonally important trophic resource for this species. By capturing 15 bats and radio-tracking the four with the most fish remains in their droppings, we also identified fishing areas, including a single fishing ground comprising several ponds within a golf course. Ponds hold a high density of G. holbrooki, suggesting that the amount of fish at the water surface may be the principal factor triggering fishing. The observed six-fold increase in percentage of consumed fish across the study period may be related to recent pond-building in the area. We discuss whether this quick behavioral response is a novel feature of M. capaccinii or an intrinsic feature that has erupted and faded locally along the species' history. PMID:24312200

  7. Fishing long-fingered bats (Myotis capaccinii) prey regularly upon exotic fish.

    PubMed

    Aizpurua, Ostaizka; Garin, Inazio; Alberdi, Antton; Salsamendi, Egoitz; Baagøe, Hans; Aihartza, Joxerra

    2013-01-01

    The long-fingered bat Myotis capaccinii is a European trawling bat reported to feed on fish in several Mediterranean locations, but the ecological circumstances of this behavior have not yet been studied. To elucidate the importance of fishing in this bat's diet, we evaluated the frequency and seasonal variation of fish remains in 3,000 fecal pellets collected from M. capaccinii at a nursery roost in Dénia (Eastern Iberian Peninsula) in 2008, 2009, and 2010. Fish consumption occurred evenly throughout the year. All otoliths found in feces were identified as belonging to the surface-feeding fish Gambusia holbrooki. Measuring otoliths, we estimated that the mean size of consumed fish was significantly smaller than the mean measured for available fish, suggesting that the long-fingered bat's relatively small body may constrain its handling of larger prey. Of note, one bat had eaten 15 fish, showing that fish may be a locally or seasonally important trophic resource for this species. By capturing 15 bats and radio-tracking the four with the most fish remains in their droppings, we also identified fishing areas, including a single fishing ground comprising several ponds within a golf course. Ponds hold a high density of G. holbrooki, suggesting that the amount of fish at the water surface may be the principal factor triggering fishing. The observed six-fold increase in percentage of consumed fish across the study period may be related to recent pond-building in the area. We discuss whether this quick behavioral response is a novel feature of M. capaccinii or an intrinsic feature that has erupted and faded locally along the species' history. PMID:24312200

  8. [Evaluation of Antilles fish ciguatoxicity by mouse and chick bioassays].

    PubMed

    Pottier, I; Vernoux, J P

    2003-03-01

    Ciguatera is a common seafood poisoning in Western Atlantic and French West Indies. Ciguatera fish poisoning in the Caribbean is a public health problem. A toxicological study was carried out on 178 Caribbean fish specimens (26 species) captured off Guadeloupe and Saint Barthelemy between 1993 and 1999. The mouse bioassay and the chick feeding test were used to control fish edibility. Ciguatoxins presence was assumed when symptomatology was typical of ciguatera in mouse and chick. Fishes were classified in three groups: non toxic fish (edible), low toxic fish (not edible) and toxic fish (not edible). 75% of fishes were non toxic. Toxic fish specimens belonged to four families of high trophic level carnivores: Carangidae, Lutjanidae, Serranidae et Sphyraenidae. Percentages of toxic fishes to humans reached 55% for Caranx latus and 33% for Caranx bartholomaei and Caranx lugubris. Only a significant correlation between weight and toxicity was only found for C. latus and snappers. Small carnivorous groupers (Serranidae) were also toxic. Atoxic fish species were (a) pelagic fish (Coryphaena hippurus, Auxis thazard and Euthynnus pelamis), (b) invertebrates feeders (Malacanthus plumieri, Balistes vetula), (c) small high-risk fish or (d) fish of edible benthic fish families. Liver of four fishes (Mycteroperca venenosa, Caranx bartholomaei, Seriola rivoliana, Gymnothorax funebris) contained ciguatoxins at a significant level although their flesh was safe. This study confirms the usefulness of mouse and chick bioassays for sanitary control of fish. PMID:12784589

  9. Numerical simulation and analysis of cavitation flows in a double suction centrifugal pump

    NASA Astrophysics Data System (ADS)

    Meng, G.; Tan, L.; Cao, S. L.; Jian, W.; Liu, W. W.; Jiang, D. J.

    2015-01-01

    Cavitation is an unsteady phenomenon, which is nearly inevitable in pumps. It would degrade the pump performance, generate vibrations and noises, and even erode pump flow passage components. The double suction centrifugal pump at design flow rate and large flow rate is numerically simulated using the k-ω turbulence model and the mass transport cavitation model. As a result, the calculated variation of pump head with pump inlet pressure agreed well with the experimental data. The results demonstrate that the numerical model and method can accurately predict the cavitation flows in a double suction centrifugal pump. The cavitation characteristics are analysed in great details. In addition, based on the calculation results, the reason that the plunge of pump head curve is revealed. It is found that the steep fall of pump head happens when the cavity reaches the blade to blade throat and the micro-vortex group appears at the back of the blade suction side. At the same time, this practice can provide guidance for the optimal design of double suction pumps.

  10. Experiments with a Wing Model from which the Boundary Is Removed by Suction

    NASA Technical Reports Server (NTRS)

    Schrenk, Oskar

    1929-01-01

    The present report deals with a series of tests made for the purpose of improving flow conditions about wings by applying the suction principle (increase of the lift coefficient and reduction of the drag about very thick wing sections). Though not conclusive, the report contains interesting results.

  11. Capillary Suction Time. Operational Control Tests for Wastewater Treatment Facilities. Instructor's Manual [and] Student Workbook.

    ERIC Educational Resources Information Center

    Wooley, John F.

    Capillary suction time is time required for the liquid phase of a treated sludge to travel through 1 centimeter of media (blotter or filter paper). Designed for individuals who have completed National Pollutant Discharge Elimination System (NPDES) level 1 laboratory training skills, this module provides waste water treatment plant operators with…

  12. Response of skirted suction caissons to monotonic lateral loading in saturated medium sand

    NASA Astrophysics Data System (ADS)

    Li, Da-yong; Zhang, Yu-kun; Feng, Ling-yun; Guo, Yan-xue

    2014-08-01

    Monotonic lateral load model tests were carried out on steel skirted suction caissons embedded in the saturated medium sand to study the bearing capacity. A three-dimensional continuum finite element model was developed with Z_SOIL software. The numerical model was calibrated against experimental results. Soil deformation and earth pressures on skirted caissons were investigated by using the finite element model to extend the model tests. It shows that the "skirted" structure can significantly increase the lateral capacity and limit the deflection, especially suitable for offshore wind turbines, compared with regular suction caissons without the "skirted" at the same load level. In addition, appropriate determination of rotation centers plays a crucial role in calculating the lateral capacity by using the analytical method. It was also found that the rotation center is related to dimensions of skirted suction caissons and loading process, i.e. the rotation center moves upwards with the increase of the "skirted" width and length; moreover, the rotation center moves downwards with the increase of loading and keeps constant when all the sand along the caisson's wall yields. It is so complex that we cannot simply determine its position like the regular suction caisson commonly with a specified position to the length ratio of the caisson.

  13. Numerical investigation of sediment erosion to the impeller in a double-suction centrifugal pump

    NASA Astrophysics Data System (ADS)

    Yang, C. X.; Dong, F. D.; Cheng, X. R.

    2013-12-01

    Based on Euler-Lagrange multiphase flow model and Finnie ductile material erosion model, using phase coupled SIMPLE algorithm, k-e RNG turbulence model and Reynolds Averaged Navier-Stokes (RANS) equation, the solid-liquid two-phase flows in a double-suction centrifugal pump is simulated. The erosion rate and solid mass concentration distribution on the pressure and suction surfaces of blades were obtained in different situations, which include different solid mass concentration (2.17kg/m3, 8.66kg/m3 and 14kg/m3) and different sediment diameter (0.019mm, 0.036mm, and 0.076mm). By comparisons of the test and numerical simulation values, the reliability of numerical calculation method has been verified. The numerical simulation result obtained show that the Finnie ductile material erosion model can accurately predict the erosion rate and erosion areas on the impeller. The erosion rate is increases with solid sediment diameter or solid mass concentration increasing. The main erosion areas on the pressure surface of blades near the blade inlet and outlet and close to the hub, and on the suction surface of blades near the blade inlet and close to the hub. For different sediment diameter or solid mass concentration, the erosion rate on the pressure surface of blades is always greater than that on its suction surface.

  14. Instruction Workbook for Tracheostomy Suctioning and Misting in a School Setting.

    ERIC Educational Resources Information Center

    Wolf, Karen McKinney; Roach, Antionette Andolfatto

    The handbook presents California guidelines for training school personnel to provide skilled nursing procedures such as tracheostomy suctioning and misting for students with special health needs. The workbook begins with an overview of the anatomy and function of the respiratory system, specifically breathing mechanics. Part 2 considers the…

  15. DNS on control of laminar-turbulent transition in channel flow with suction and blowing

    NASA Astrophysics Data System (ADS)

    Yamamoto, Kiyoshi; Murase, Takeo; Floryan, J. M.

    1992-11-01

    Numerical simulation of laminar-turbulent transition in channel flow with spatially periodic suction/blowing from its channel walls is conducted with a spectral method based on the Fourier spectral method. Reynolds number is fixed on a subcritical value, 5,000, and the influence of both amplitude and wave number of the suction/blowing on the transition is investigated. When the amplitude is small, the transition does not occur because the suction/blowing gives only a slight effect to the basic flow and the resulted flow remains stable to all three-dimensional small disturbances. On the other hand, when the amplitude is a large value, the transition occurs in a finite time, and finally it is obtained instantaneously with a huge value of the amplitude. It is found that the suction/blowing makes the separation ridges on the wall, which may simulate a wall roughness. The transition times are obtained for the moderately large amplitudes and wave numbers, obey nearly a minus two power law dependence on the ratio of amplitude to wave number.

  16. Low-speed Investigation of a Semisubmerged Air Scoop with and Without Boundary-layer Suction

    NASA Technical Reports Server (NTRS)

    Pierpont, P Kenneth; Howell, Robert R

    1951-01-01

    A preliminary low-speed investigation has been made of an air scoop submerged one-half the inlet height in a depression on the surface of a simulated fuselage. Boundary-layer suction was used on the steep approach ramp to improve the internal flow. A 6-degree-included-angle diffuser with an area ratio of 1.9:1 was located behind the inlet in the model. Most of the tests were conducted with an initial turbulent boundary layer believed to approximate that which would occur on the forward part of a fuselage. A few tests were made with a boundary layer about 2.5 times the thickness of the original boundary layer to determine the effect of moving the inlet further rearward on the fuselage. The effects of suction-slot location and slot width were determined and a few tests with area suction were made. The maximum quantity of suction flow was about 15 percent of the inlet flow at an inlet-velocity ratio of 0.6.

  17. 21 CFR 878.4680 - Nonpowered, single patient, portable suction apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Nonpowered, single patient, portable suction apparatus. 878.4680 Section 878.4680 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  18. 21 CFR 878.4680 - Nonpowered, single patient, portable suction apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nonpowered, single patient, portable suction apparatus. 878.4680 Section 878.4680 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  19. 21 CFR 878.4680 - Nonpowered, single patient, portable suction apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Nonpowered, single patient, portable suction apparatus. 878.4680 Section 878.4680 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  20. 21 CFR 878.4680 - Nonpowered, single patient, portable suction apparatus.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Nonpowered, single patient, portable suction apparatus. 878.4680 Section 878.4680 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  1. 21 CFR 878.4680 - Nonpowered, single patient, portable suction apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Nonpowered, single patient, portable suction apparatus. 878.4680 Section 878.4680 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices §...

  2. Effect of suction-dependent soil deformability on landslide susceptibility maps

    NASA Astrophysics Data System (ADS)

    Lizarraga, Jose J.; Buscarnera, Giuseppe; Frattini, Paolo; Crosta, Giovanni B.

    2016-04-01

    This contribution presents a physically-based, spatially-distributed model for shallow landslides promoted by rainfall infiltration. The model features a set of Factor of Safety values aimed to capture different failure mechanisms, namely frictional slips with limited mobility and flowslide events associated with the liquefaction of the considered soils. Indices of failure associated with these two modes of instability have been derived from unsaturated soil stability principles. In particular, the propensity to wetting-induced collapse of unsaturated soils is quantified through the introduction of a rigid-plastic model with suction-dependent yielding and strength properties. The model is combined with an analytical approach (TRIGRS) to track the spatio-temporal evolution of soil suction in slopes subjected to transient infiltration. The model has been tested to reply the triggering of shallow landslides in pyroclastic deposits in Sarno (1998, Campania Region, Southern Italy). It is shown that suction-dependent mechanical properties, such as soil deformability, have important effects on the predicted landslide susceptibility scenarios, resulting on computed unstable zones that may encompass a wide range of slope inclinations, saturation levels, and depths. Such preliminary results suggest that the proposed methodology offers an alternative mechanistic interpretation to the variability in behavior of rainfall-induced landslides. Differently to standard methods the explanation to this variability is based on suction-dependent soil behavior characteristics.

  3. Endoscopic en bloc resection of an exophytic gastrointestinal stromal tumor with suction excavation technique.

    PubMed

    Choi, Hyuk Soon; Chun, Hoon Jai; Kim, Kyoung-Oh; Kim, Eun Sun; Keum, Bora; Jeen, Yoon-Tae; Lee, Hong Sik; Kim, Chang Duck

    2016-06-21

    Here, we report the first successful endoscopic resection of an exophytic gastrointestinal stromal tumor (GIST) using a novel perforation-free suction excavation technique. A 49-year-old woman presented for further management of a gastric subepithelial tumor on the lesser curvature of the lower body, originally detected via routine upper gastrointestinal endoscopy. Abdominal computed tomography and endoscopic ultrasound showed a 4-cm extraluminally protruding mass originating from the muscularis propria layer. The patient firmly refused surgical resection owing to potential cardiac problems, and informed consent was obtained for endoscopic removal. Careful dissection and suction of the tumor was repeated until successful extraction was achieved without serosal injury. We named this procedure the suction excavation technique. The tumor's dimensions were 3.5 cm × 2.8 cm × 2.5 cm. The tumor was positive for C-KIT and CD34 by immunohistochemical staining. The mitotic count was 6/50 high-power fields. The patient was followed for 5 years without tumor recurrence. This case demonstrated the use of endoscopic resection of an exophytic GIST using the suction excavation technique as a potential therapy without surgical resection. PMID:27340363

  4. Endoscopic en bloc resection of an exophytic gastrointestinal stromal tumor with suction excavation technique

    PubMed Central

    Choi, Hyuk Soon; Chun, Hoon Jai; Kim, Kyoung-Oh; Kim, Eun Sun; Keum, Bora; Jeen, Yoon-Tae; Lee, Hong Sik; Kim, Chang Duck

    2016-01-01

    Here, we report the first successful endoscopic resection of an exophytic gastrointestinal stromal tumor (GIST) using a novel perforation-free suction excavation technique. A 49-year-old woman presented for further management of a gastric subepithelial tumor on the lesser curvature of the lower body, originally detected via routine upper gastrointestinal endoscopy. Abdominal computed tomography and endoscopic ultrasound showed a 4-cm extraluminally protruding mass originating from the muscularis propria layer. The patient firmly refused surgical resection owing to potential cardiac problems, and informed consent was obtained for endoscopic removal. Careful dissection and suction of the tumor was repeated until successful extraction was achieved without serosal injury. We named this procedure the suction excavation technique. The tumor’s dimensions were 3.5 cm × 2.8 cm × 2.5 cm. The tumor was positive for C-KIT and CD34 by immunohistochemical staining. The mitotic count was 6/50 high-power fields. The patient was followed for 5 years without tumor recurrence. This case demonstrated the use of endoscopic resection of an exophytic GIST using the suction excavation technique as a potential therapy without surgical resection. PMID:27340363

  5. Feeding Behaviour, Swimming Activity and Boldness Explain Variation in Feed Intake and Growth of Sole (Solea solea) Reared in Captivity

    PubMed Central

    Mas-Muñoz, Julia; Komen, Hans; Schneider, Oliver; Visch, Sander W.; Schrama, Johan W.

    2011-01-01

    The major economic constraint for culturing sole (Solea solea) is its slow and variable growth. The objective was to study the relationship between feed intake/efficiency, growth, and (non-) feeding behaviour of sole. Sixteen juveniles with an average (SD) growth of 2.7 (1.9) g/kg0.8/d were selected on their growth during a 4-week period in which they were housed communally with 84 other fish. Selected fish were housed individually during a second 4-week period to measure individual feed intake, growth, and behaviour. Fish were hand-fed three times a day during the dark phase of the day until apparent satiation. During six different days, behaviour was recorded twice daily during 3 minutes by direct observations. Total swimming activity, frequency of burying and of escapes were recorded. At the beginning and end of the growth period, two sequential behavioural tests were performed: “Novel Environment” and “Light Avoidance”. Fish housed individually still exhibited pronounced variation in feed intake (CV = 23%), growth (CV = 25%) and behavior (CV = 100%). Differences in feed intake account for 79% of the observed individual differences in growth of sole. Fish with higher variation in feed intake between days and between meals within days had significantly a lower total feed intake (r = −0.65 and r = −0.77) and growth. Active fish showed significantly higher feed intake (r = 0.66) and growth (r = 0.58). Boldness during both challenge tests was related to fast growth: (1) fish which reacted with a lower latency time to swim in a novel environment had significantly higher feed intake (r = −0.55) and growth (r = −0.66); (2) fish escaping during the light avoidance test tended to show higher feed intake (P<0.1) and had higher growth (P<0.05). In conclusion, feeding consistency, swimming activity in the tank, and boldness during behavioral tests are related to feed intake and growth of sole in captivity. PMID:21738651

  6. Fish Facts

    MedlinePlus

    ... not eat any fish because they worry about mercury in seafood. Mercury is a metal that, at high levels, can ... many types of seafood have little or no mercury at all. So your risk of mercury exposure ...

  7. Designer Fish.

    ERIC Educational Resources Information Center

    Hall, William R., Jr.

    1990-01-01

    Described is an activity in which students are asked to design a fish that would survive in a natural system. A project to computerize the activity is discussed. The development of this artificial intelligence software is detailed. (CW)

  8. Fish Allergy

    MedlinePlus

    ... specific fish used on the label. Read all product labels carefully before purchasing and consuming any item. Ingredients ... Getting Started Newly Diagnosed Emergency Care Plan Food Labels Mislabeled Products Tips for Managing Food Allergies Resources For... Most ...

  9. Subcutaneous versus intraarticular closed suction indwelling drainage after total knee arthroplasty: A randomised control trial

    PubMed Central

    Yang, Jae-Hyuk; Yoon, Jung-Ro; Dahuja, Anshul; Song, Seungyeop

    2016-01-01

    Background: Total knee arthroplasty (TKA) is widely accepted treatment for moderate or severe osteoarthritis and rheumatoid arthritis. Significant blood loss can be seen during the early postoperative period where a blood transfusion may be necessary. Closed suction drainage is known to prevent the formation of hematomas in the operative field, decrease tension on incisions, diminish delayed wound healing and reduce the risk of infection. Subcutaneous indwelling closed suction drainage method has been known to be beneficial and an alternative to the intraarticular indwelling method. This prospective randomized study was to compare the visible, hidden, total blood loss and postoperative hemodynamic change of subcutaneous and intraarticular indwelling closed suction drainage method after TKA. Materials and Methods: One hundred and sixty patients with primary osteoarthritis who underwent unilateral TKA were enrolled; group A with subcutaneous (n = 78) and group B with intraarticular (n = 79) indwelling closed suction drainage method. Total blood loss, visible blood loss, internal blood loss, postoperative day 1, 5th, 10th day hemoglobin, hematocrit levels were compared. Allogeneic blood transfusion rate and complications related to soft tissue hematoma formation were additionally compared. Results: Allogenic transfusion requirements between subcutaneous drainage group and intraarticular drainage groups (6.4% vs. 24.1%) were significantly different (P = 0.002). Although the minor complications such as the incidence of bullae formation and the ecchymosis were higher in the subcutaneous indwelling group, the functional outcome at postoperative 2 year did not demonstrate the difference from intraarticular drainage group. Conclusion: Subcutaneous indwelling closed suction drainage method is a reasonable option after TKA for reduction of postoperative bleeding and transfusion rate. PMID:26955178

  10. The Effects of Suction and Pin/Lock Suspension Systems on Transtibial Amputees’ Gait Performance

    PubMed Central

    Gholizadeh, Hossein; Abu Osman, Noor Azuan; Eshraghi, Arezoo; Ali, Sadeeq

    2014-01-01

    Background The suction sockets that are commonly prescribed for transtibial amputees are believed to provide a better suspension than the pin/lock systems. Nevertheless, their effect on amputees’ gait performance has not yet been fully investigated. The main intention of this study was to understand the potential effects of the Seal-in (suction) and the Dermo (pin/lock) suspension systems on amputees’ gait performance. Methodology/Principal Findings Ten unilateral transtibial amputees participated in this prospective study, and two prostheses were fabricated for each of them. A three-dimensional motion analysis system was used to evaluate the temporal-spatial, kinematics and kinetics variables during normal walking. We also asked the participants to complete some part of Prosthesis Evaluation Questionnaire (PEQ) regarding their satisfaction and problems with both systems. The results revealed that there was more symmetry in temporal-spatial parameters between the prosthetic and sound limbs using the suction system. However, the difference between two systems was not significant (p<0.05). Evaluation of kinetic data and the subjects’ feedback showed that the participants had more confidence using the suction socket and the sockets were more fit for walking. Nevertheless, the participants had more complaints with this system due to the difficulty in donning and doffing. Conclusion It can be concluded that even though the suction socket could create better suspension, fit, and gait performance, overall satisfaction was higher with the pin/lock system due to easy donning and doffing of the prosthesis. Trial Registration irct.ir IRCT2014012816395N1 PMID:24827560

  11. Suction Drain Tip Culture after Spine Surgery: Can It Predict a Surgical Site Infection?

    PubMed Central

    Ahn, Jae-Sung; Park, Eugene; Park, Il-Young; Lee, Jae Won

    2015-01-01

    Study Design Retrospective clinical study. Purpose To assess the diagnostic value of suction drain tip culture in patients undergoing primary posterior spine surgery. Overview of Literature To date, the diagnostic value of suction drain tip culture for predicting surgical site infection (SSI) has not been firmly established in orthopedic or spinal surgery. Methods In total, 133 patients who underwent primary posterior spine surgery from January 2013 to April 2015 were included in this retrospective study. Patients diagnosed with infective disease or condition was excluded. The suction drain tip was cut off approximately 5 cm from its far end. The sample was sent to the microbiological laboratory of the hospital for culture analysis. Any signs of infection, such as wound discharge or dehiscence, fever, chills, or chronic pain, were recorded. The culture outcome, identification of bacteria, and postoperative transition of the serum C-reactive protein level were also recorded in all patients. The wounds were followed up for a minimum of 3 months. Results A positive drain tip culture was found in 48 patients (36.1%), of whom, 6 developed SSI. The sensitivity of drain tip culture for SSI after primary posterior spine surgery was 60.0%, and the specificity was 65.9%. The association between the incidence of positive suction tip culture and SSI was not statistically significant. Among the 48 positive drain tip cultures, there was no significant association between the occurrence of SSI and virulence of isolated bacteria. There was no significant association between drain tip culture positivity and the duration of drainage, or between the rate of SSI and duration of drainage. Conclusions Suction drain tip culture analysis is a poor predictor of SSI after primary posterior spine surgery. Routine use of a drain tip culture is not supported by the results of this study. PMID:26713117

  12. Facial Expression as an Indicator of Pain in Critically Ill Intubated Adults During Endotracheal Suctioning

    PubMed Central

    Rahu, Mamoona Arif; Grap, Mary Jo; Cohn, Jeffrey F.; Munro, Cindy L.; Lyon, Debra E.; Sessler, Curtis N.

    2013-01-01

    Background Facial expression is often used to evaluate pain in noncommunicative critically ill patients. Objectives To describe facial behavior during endotracheal suctioning, determine facial behaviors that characterize the pain response, and describe the effect of patient factors on facial behavior during pain response. Methods Fifty noncommunicative patients receiving mechanical ventilation were video recorded during 2 phases (rest and endotracheal suctioning). Pain ratings were gathered by using the Behavioral Pain Scale. Facial behaviors were coded by using the Facial Action Coding System for 30 seconds for each phase. Results Fourteen facial actions were associated more with endotracheal suctioning than with rest (z = 5.78; P < .001). The sum of intensity of the 14 actions correlated with total mean scores on the Behavioral Pain Scale (ρ = 0.71; P < .001) and with the facial expression component of the scale (ρ = 0.67; P < .001) during suctioning. In stepwise multivariate analysis, 5 pain-relevant facial behaviors (brow raiser, brow lower, nose wrinkling, head turned right, and head turned up) accounted for 71% of the variance (adjusted R2 = 0.682; P < .001) in pain response. The sum of intensity of the 5 actions correlated with total mean scores on the behavioral scale (ρ = 0.72; P < .001) and with the facial expression component of that scale (ρ = 0.61; P < .001) during suctioning. Patient factors had no association with pain intensity scores. Conclusions Upper facial expressions are most frequently activated during pain response in noncommunicative critically ill patients and might be a valid alternative to self-report ratings. PMID:23996421

  13. Assessment of pain during endotracheal suction in the pediatric intensive care unit.

    PubMed

    Sönmez Düzkaya, Duygu; Kuğuoğlu, Sema

    2015-02-01

    This research was planned as a two-level definitive and comparative study to evaluate pain during endotracheal suction (ETS) in pediatric intensive care units (PICUs). This study was comprised of patients admitted to and the nurses working in the PICU. Cases were selected among PICU patients (N = 65) who met the study criteria and nurses (N = 18) who cared for them from January 1 to July 2, 2008. Routine ETS was applied as the first level of the study. For the second level, an inquiry on the knowledge of nurses about suction was given to the nurses, and they were asked to apply suction according to the guidelines they were given. All the obtained data were evaluated by statistical package for the social sciences (SPSS) for Windows 14.0. In summary, 33.8% (n = 22) of the patients were between ages 1 and 12 months, and 64.6% (n = 42) were boys. Although group 2 patients (patient who is in experimental group) had higher scores on the Wong-Baker faces pain rating and Face, Legs, Activity, Cry, Consolability scales, no statistical difference was found between the two groups (p > .05). Patients who received bolus doses of analgesia and sedative drugs had lower Wong-Baker faces pain rating (4.38 ± 0.96; n = 4) and Face, Legs, Activity, Cry, Consolability scores (4.61 ± 1.94; n = 4) (p > .05). According to these findings, the patients were distressed because of the pain related with suction. Therefore, it is recommended that suction guidelines be used in PICUs during ETS. PMID:24957815

  14. The effect of expiratory rib cage compression before endotracheal suctioning on the vital signs in patients under mechanical ventilation

    PubMed Central

    Bousarri, Mitra Payami; Shirvani, Yadolah; Agha-Hassan-Kashani, Saeed; Nasab, Nouredin Mousavi

    2014-01-01

    Background: In patients undergoing mechanical ventilation, mucus production and secretion is high as a result of the endotracheal tube. Because endotracheal suction in these patients is essential, chest physiotherapy techniques such as expiratory rib cage compression before endotracheal suctioning can be used as a means to facilitate mobilizing and removing airway secretion and improving alveolar ventilation. As one of the complications of mechanical ventilation and endotracheal suctioning is decrease of cardiac output, this study was carried out to determine the effect of expiratory rib cage compression before endotracheal suctioning on the vital signs in patients under mechanical ventilation. Materials and Methods: This study was a randomized clinical trial with a crossover design. The study subjects included 50 mechanically ventilated patients, hospitalized in intensive care wards of Valiasr and Mousavi hospitals in Zanjan, Iran. Subjects were selected by consecutive sampling and randomly allocated to groups 1 and 2. The patients received endotracheal suctioning with or without rib cage compression, with a minimum of 3 h interval between the two interventions. Expiratory rib cage compression was performed for 5 min before endotracheal suctioning. Vital signs were measured 5 min before and 15 and 25 min after endotracheal suctioning. Data were recorded on a data recording sheet. Data were analyzed using paired t-tests. Results: There were statistically significant differences in the means of vital signs measured 5 min before with 15 and 25 min after endotracheal suctioning with rib cage compression (P < 0. 01). There was no significant difference in the means of diastolic pressure measured 25 min after with baseline in this stage). But on the reverse mode, there was a significant difference between the means of pulse and respiratory rate 15 min after endotracheal suctioning and the baseline values (P < 0.002). This effect continued up to 25 min after endotracheal

  15. A prospective, randomized study of ventilator-associated pneumonia in patients using a closed vs. open suction system.

    PubMed

    Zeitoun, Sandra Salloum; de Barros, Alba Lúcia Botura Leite; Diccini, Solange

    2003-07-01

    The objective of this study was to verify the incidence of nosocomial pneumonia in intubated and extended mechanically ventilated patients having endotracheal suctioning by an open vs. closed suction method aiming to decrease nosocomial pneumonia. Twenty-four (51.1%) patients received open-tracheal suction and 23 (48.9%) received closed-tracheal suction. The inclusion criteria were: surgical and medical patients older than 13 years, undergoing mechanical ventilation for more than 48 hours. Additional data were gathered using the Acute Physiology and Chronic Health Evaluation II, and details on smoking, alcoholism, diabetes mellitus, renal failure, previous lung disease, and previous use of antibiotics, steroids, H2 antagonists and antacids. Among the 24 patients having open-tracheal suction, 11 developed nosocomial pneumonia while of the 23 patients undergoing closed-tracheal suction, seven developed infection (P = 0.278). Risk factors for nosocomial pneumonia were not significantly different between the two groups. In the final logistical regression model the following variables remained: groups (open and closed) [odds ratio (OR) = 0.014; confidence interval (CI) = 0.001-0.416; P = 0.014] and use of prior antibiotics (OR = 2.297; CI = 1.244-4.242; P = 0.008). Use of a closed suction system did not decrease the incidence of nosocomial pneumonia when compared with the open system. The exogenous risk factors were the most important for acquiring this infection. PMID:12790861

  16. Performance of a short annular dump diffuser using suction-stabilized vortices at inlet Mach numbers to 0.41

    NASA Technical Reports Server (NTRS)

    Smith, J. M.; Juhasz, A. J.

    1978-01-01

    A short, annular dump diffuser was designed to use suction to establish stabilized vortices on both walls for improved flow expansion in the region of an abrupt area change. The diffuser was tested at near ambient inlet pressure and temperature. The overall diffuser area ratio was 4.0. The inlet height was 2.54 cm and the exit pitot-static rakes were located at a distance from the vortex fence equal to two or six times the inlet height. Performance data were taken at near ambient temperature and pressure for nominal inlet Mach numbers of 0.18 to 0.41 with suction rates of 0 to 18 percent of the total inlet airflow. The exit velocity profile could be shifted toward either wall by adjusting the inner- or outer-wall suction rate. Symmetrical exit velocity profiles were unstable, with a tendency to shift back to hub- or tip-weighted profile. Diffuser effectiveness was increased from about 47 percent without suction to over 85 percent at a total suction rate of about 14 percent. The diffuser total pressure losses at inlet Mach numbers of 0.18 and 0.41 decreased from 1.1 and 5.6 percent without suction to 0.48 and 5.2 percent at total suction rates of 14.4 and 5.6 percent, respectively.

  17. Feeding competition between larval lake whitefish and lake herring

    USGS Publications Warehouse

    Savino, Jacqueline F.; Hudson, Patrick L.

    1995-01-01

    The potential for competition for food between larval lake whitefish (Coregonus clupeaformis) and lake herring (C. artedi) 1- to 8-wk of age was explored in a series of 1-h laboratory feeding studies. Feeding started at 2-wk post-hatch. Learning and fish size appear to be more important than prey density at the onset of feeding. Species differed in their feeding behavior and consumption noticeably by 5-wk and substantially by 8-wk. Lake whitefish generally were more aggressive foragers than lake herring, attacking and capturing more prey. At high plankton density at 8-wk, lake herring feeding was depressed in mixed-fish treatments. This difference in competitive food consumption between the two coregonids occurs at a critical life stage, and when combined with other biotic and abiotic factors, may have a significant impact on recruitment.

  18. Experimental Study of the Effects of Finite Surface Disturbances and Angle of Attack on the Laminar Boundary Layer of an NACA 64A010 Airfoil with Area Suction

    NASA Technical Reports Server (NTRS)

    Schwartzberg, Milton A; Braslow, Albert L

    1952-01-01

    A Langley low-turbulence wind-tunnel investigation of a porous NACA 64A010 airfoil section has been made to determine the effectiveness of area suction in maintaining full-chord laminar flow behind finite disturbances and at angles of attacks other than 0 degrees. Aero suction resulted in only a small increase in the size of a finite disturbance required to cause premature boundary-layer transition as compared with that for the airfoil without suction. Combined wake and suction drags lower than the drag of the plain airfoil were obtained through a range of low lift coefficient by the use of area suction.

  19. Visualization of Rotor Tip Secondary Flows with Blade Tip Air Discharge and Suction in a Low-speed Turbine

    NASA Technical Reports Server (NTRS)

    Kofskey, Milton G; Allen, Hubert W

    1956-01-01

    Smoke was used to visualize outer-wall secondary flows in a low-speed turbine utilizing rotor tip air discharge and suction. Photographs as well as visual observations of the effect of tip air discharge and suction were made by independently varying the direction and quantity of the tip air discharge and suction, and varying tip clearance, and main-stream air speed. In addition, the cross-sectional area of the hollow blade discharge opening was varied for the case of tip air discharge.

  20. Design and fabrication of large suction panels with perforated surfaces for laminar flow control testing in a transonic wind tunnel

    NASA Technical Reports Server (NTRS)

    Maddalon, D. V.; Poppen, W. A., Jr.

    1986-01-01

    Considerable progress has been made in the development of perforated suction surface material for laminar flow control applications. Electron-beam perforated titaniuum skin was used as the suction surface. Critical issues related to suction panel manufacturing were identified and largely resolved. The final product included fabrication of a 7-foot chord by 7-foot span perforated laminar flow control wind tunnel model. Techniques used can be adapted to modern aircraft production lines. The report includes details on panel instrumentation and other features required for testing in a transonic pressure tunnel.