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Maarten Van Den Buuse - One of the best experts on this subject based on the ideXlab platform.

  • involvement of serotonin1a receptors in cardiovascular responses to stress a Radio Telemetry study in four rat strains
    European Journal of Pharmacology, 2005
    Co-Authors: Maarten Van Den Buuse, Nico Wegener
    Abstract:

    We studied the effect of treatment with the serotonin-1A (5-HT1A) receptor ligands buspirone, 8-hydroxy-di-propyl-aminotetralin (8-OHDPAT), and (8-[2-(2,3-dihydro-1,4-benzodioxin-2-yl-methylamino)ethyl]-8-azaspiro[4,5]decane-7,9-dione methyl sulphonate (MDL73,005EF) on blood pressure and heart rate increases to open field stress. We compared Spontaneously Hypertensive Rats (SHR), Fawn–Hooded (FH) rats, Wistar–Kyoto (WKY) rats, and Sprague–Dawley (SD) rats instrumented with Radio-Telemetry probes. Buspirone treatment reduced the blood pressure increase in SHR, FH rats, and WKY rats and heart rate increase in FH rats and WKY rats. 8-OH-DPAT treatment reduced the blood pressure increase in FH rats and WKY rats, but had no effect in SHR and enhanced the pressor response in SD rats. This treatment reduced the heart rate increase in FH rats and WKY rats only. Similarly, MDL73,005EF treatment reduced the blood pressure increase in FH rats and WKY rats, but had no effect in SHR and enhanced this response in SD rats. Little effect of this treatment was seen on heart rate changes. For comparison, diazepam treatment abolished the pressor response in SD rats and reduced it in FH rats and WKY rats, but not SHR. Differential effects of the treatments were also seen between strains for locomotor activity in the open field, although behavioural changes could not explain the effects of the drugs on cardiovascular responses. These data suggest that 5-HT1A receptors are involved in cardiovascular stress responses; however, the extent of this involvement differs between rat strains and the drugs used. These results could be important for our understanding of possible anxiolytic properties of antipsychotic drugs with affinity for the 5-HT1A receptor. D 2004 Elsevier B.V. All rights reserved.

  • 24-hour recordings of blood pressure, heart rate and behavioural activity in rabbits by Radio-Telemetry: effects of feeding and hypertension.
    Physiology & Behavior, 1997
    Co-Authors: Maarten Van Den Buuse, Simon C. Malpas
    Abstract:

    Abstract van den Buuse, M. and S. C. Malpas. 24-Hour recordings of blood pressure, heart rate and behavioural activity in rabbits by Radio-Telemetry: Effects of feeding and hypertension. Physiol Behav 62(1) 83–89, 1997.—We used Radio-Telemetry to measure 24-hour rhythms of systolic, diastolic and mean blood pressure, heart rate and behavioural activity in conscious rabbits, which were maintained under normal day/night rhythms and restricted feeding. Over three consecutive days, all variables showed little change between day-period and night-period, except for a pronounced rise in the afternoon, coinciding with the presentation of pellet food. Mean blood pressure increased during this period from baseline values between 78–82 mm Hg to a peak of 89–91 mm Hg. At the same time heart rate rose from baseline values of 147–161 b/min to a peak of 206–234 b/min and behavioural activity scores rose from 11–31 counts/h to a peak of 52–81 counts/h. Changing the time at which pellet food was presented to the rabbits from the early afternoon to the early morning, caused a complete and immediate shift of the peak of blood pressure and heart rate to the morning period. Chronic intravenous infusion of angiotensin II caused a significant increase in blood pressure (24-hour average: 80 ± 1 vs. 114 ± 7 mm Hg) but did not alter basal heart rate or behavioural activity. The increase in heart rate and blood pressure seen with food presentation was attenuated with angiotensin II infusion. These data show that in rabbits diurnal changes in blood pressure, heart rate and activity were determined to a large extent by timed feeding. In addition, in rabbits with angiotensin-induced hypertension the food-induced changes in blood pressure and heart rate were blunted.

  • circadian rhythms of blood pressure heart rate and locomotor activity in spontaneously hypertensive rats as measured with Radio Telemetry
    Physiology & Behavior, 1994
    Co-Authors: Maarten Van Den Buuse
    Abstract:

    Abstract Circadian rhythms of blood pressure, heart rate, and locomotor activity were measured with implanted Radio-Telemetry transmitters in conscious, unrestrained spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). During the light period (0600 to 1800 h) systolic, diastolic, and mean blood pressure, heart rate, and locomotor activity were lower than during the dark period (1800 to 0600 h). During the first and the last hour of the dark period, all parameters showed a relative peak when compared to values during the rest of the night. The pattern of circadian changes in blood pressure, heart rate, or behavior was essentially similar in SHR and WKY. Blood pressure values were always higher in SHR than in WKY, but there was no general strain difference in heart rate or locomotor activity values. The administration of hydralazine in the drinking water resulted in a significant decrease in blood pressure in SHR and WKY, and a suppression of the difference between light-phase values and dark-phase values. By contrast, heart rate showed an overall increase in both strains, whereas locomotor activity was largely unaffected. These data show the validity of Telemetry as a means of measuring circadian rhythms of blood pressure, heart rate, and behavior in freely moving rats. Apart from their characteristic hypertension, SHR show few differences with WKY with respect to other parameters, such as circadian rhythmicity, baseline heart rate values, or behavior. Some of the previously published differences between SHR and WKY may have been influenced by the stress of the experimental procudures used.

Simon C. Malpas - One of the best experts on this subject based on the ideXlab platform.

  • 24-hour recordings of blood pressure, heart rate and behavioural activity in rabbits by Radio-Telemetry: effects of feeding and hypertension.
    Physiology & Behavior, 1997
    Co-Authors: Maarten Van Den Buuse, Simon C. Malpas
    Abstract:

    Abstract van den Buuse, M. and S. C. Malpas. 24-Hour recordings of blood pressure, heart rate and behavioural activity in rabbits by Radio-Telemetry: Effects of feeding and hypertension. Physiol Behav 62(1) 83–89, 1997.—We used Radio-Telemetry to measure 24-hour rhythms of systolic, diastolic and mean blood pressure, heart rate and behavioural activity in conscious rabbits, which were maintained under normal day/night rhythms and restricted feeding. Over three consecutive days, all variables showed little change between day-period and night-period, except for a pronounced rise in the afternoon, coinciding with the presentation of pellet food. Mean blood pressure increased during this period from baseline values between 78–82 mm Hg to a peak of 89–91 mm Hg. At the same time heart rate rose from baseline values of 147–161 b/min to a peak of 206–234 b/min and behavioural activity scores rose from 11–31 counts/h to a peak of 52–81 counts/h. Changing the time at which pellet food was presented to the rabbits from the early afternoon to the early morning, caused a complete and immediate shift of the peak of blood pressure and heart rate to the morning period. Chronic intravenous infusion of angiotensin II caused a significant increase in blood pressure (24-hour average: 80 ± 1 vs. 114 ± 7 mm Hg) but did not alter basal heart rate or behavioural activity. The increase in heart rate and blood pressure seen with food presentation was attenuated with angiotensin II infusion. These data show that in rabbits diurnal changes in blood pressure, heart rate and activity were determined to a large extent by timed feeding. In addition, in rabbits with angiotensin-induced hypertension the food-induced changes in blood pressure and heart rate were blunted.

Gunther Schlott - One of the best experts on this subject based on the ideXlab platform.

  • Reaction of common carp (Cyprinus carpio, L.) to oxygen deficiency in winter as an example for the suitability of Radio Telemetry for monitoring the reaction of fish to stress factors in pond aquaculture
    Aquaculture Research, 2006
    Co-Authors: Christian Bauer, Gunther Schlott
    Abstract:

    The reaction of common carp (Cyprinus carpio L.) in an ice- and snow-covered pond to depletion of dissolved oxygen (DO) in winter was recorded using Radio Telemetry. The carp moved from the deeper parts of the pond to the shallow areas near the tributary in search of better oxygenated water. Evidence was found that feeding occurred until December but ceased with the oxygen crisis. After the carp farmer started aeration to improve the oxygen supply, carp returned towards the deeper parts of the pond. The gross activity was significantly correlated with DO (P 0.05). The clear documentation of the carp's reaction to oxygen depletion suggests, that Radio Telemetry may be useful for investigating the effects of various stress factors on fish in pond aquaculture.

  • overwintering of farmed common carp cyprinus carpio l in the ponds of a central european aquaculture facility measurement of activity by Radio Telemetry
    Aquaculture, 2004
    Co-Authors: Christian Bauer, Gunther Schlott
    Abstract:

    Abstract In the aquaculture of farmed common carp ( Cyprinus carpio L.) in Central Europe, it is believed that carp overwinter motionless and without feeding at the bottom of the ponds. However, only a few studies have investigated the behaviour of carp in winter, and data on the overwintering of carp in ponds are rare. This paper presents some new data on the activity of overwintering farmed common carp in Central European aquaculture. Altogether, 14 carp were equipped with surgically implanted Radio Telemetry transmitters and their activity was investigated by positional tracking in a pond (2.2 ha) during the winter seasons of 1999/2000, 2000/2001 and 2001/2002. Low weight loss, WL, and good condition factor, K , suggested that overwintering was successful (WL max.=3.8%, K =1.84–2.33). The carp were found to be relatively active in winter. The mean relative distances between the estimated fish positions on two consecutive tracking sessions ranged from 27.6 to 67.9 m. These activities correlated positively with water temperature in two winter seasons ( p

Martin Wikelski - One of the best experts on this subject based on the ideXlab platform.

  • Combining Spatial and Telemetric Features for Learning Animal Movement Models
    2020
    Co-Authors: Berk Kapicioglu, Martin Wikelski, Robert E Schapire, Tamara Broderick
    Abstract:

    Abstract We introduce a new graphical model for tracking Radio-tagged animals and learning their movement patterns. The model provides a principled way to combine Radio Telemetry data with an arbitrary set of userdefined, spatial features. We describe an efficient stochastic gradient algorithm for fitting model parameters to data and demonstrate its effectiveness via asymptotic analysis and synthetic experiments. We also apply our model to real datasets, and show that it outperforms the most popular Radio Telemetry software package used in ecology. We conclude that integration of different data sources under a single statistical framework, coupled with appropriate parameter and state estimation procedures, produces both accurate location estimates and an interpretable statistical model of animal movement

  • Tracking animal location and activity with an automated Radio Telemetry system in a tropical rainforest
    Computer Journal, 2011
    Co-Authors: Roland W. Kays, Daniel Obando, Franz Kuemmeth, Jamie Mandel, Ben Hirsch, Alejandro Ortega, Sameer Tilak, Tony Fountain, Thomas Lambert, Margaret C Crofoot, George W Swenson, Martin Wikelski
    Abstract:

    How do animals use their habitat? Where do they go and what do they do? These basic questions are key not only to understanding a species’ ecology and evolution, but also for addressing many of the environmental challenges we currently face, including problems posed by invasive species, the spread of zoonotic diseases and declines in wildlife populations due to anthropogenic climate and land-use changes. Monitoring the movements and activities of wild animals can be difficult, especially when the species in question are small, cryptic or move over large areas. In this paper, we describe an Automated Radio-Telemetry System (ARTS) that we designed and built on Barro Colorado Island (BCI), Panama to overcome these challenges. We describe the hardware and software we used to implement the ARTS, and discuss the scientific successes we have had using the system, as well as the logistical challenges we faced in maintaining the system in real-world, rainforest conditions. The ARTS uses automated Radio-Telemetry receivers mounted on 40-m towers topped with arrays of directional antennas to track the activity and location of Radio-collared study animals, 24 h a day, 7 days a week. These receiving units are connected by a wireless network to a server housed in the laboratory on BCI, making these data available in real time to researchers via a web-accessible database. As long as study animals are within the range of the towers, theARTS system collects data more frequently than typical animal-borne global positioning system collars (∼12 locations/h) with lower accuracy (approximately 50 m) but at much reduced cost per tag (∼10X less expensive). The geographic range of ARTS, like all VHF Telemetry, is affected by the size of the Radio-tag as well as its position in the forest (e.g. tags in the canopy transmit farther than those on the forest floor). We present a model of signal propagation based on landscape conditions, which quantifies these effects and identifies sources of interference, including weather events and human activity.ARTS has been used to track 374 individual animals from 38 species, including 17 mammal species, 12 birds, 7 reptiles or amphibians, as well as two species of plant seeds. These data elucidate the spatio-temporal dynamics of animal activity and movement at the site and have produced numerous peer-reviewed publications, student theses, magazine articles, educational programs and film documentaries. These data are also relevant to long-term population monitoring and conservation plans. Both the successes and the failures of the ARTS system are applicable to broader sensor network applications and are valuable for advancing sensor network research.

  • large range movements of neotropical orchid bees observed via Radio Telemetry
    PLOS ONE, 2010
    Co-Authors: Martin Wikelski, Jerry Moxley, Alexander Eatonmordas, Margarita M Lopezuribe, Richard A Holland, David Moskowitz, David W Roubik, Roland W. Kays
    Abstract:

    Neotropical orchid bees (Euglossini) are often cited as classic examples of trapline-foragers with potentially extensive foraging ranges. If long-distance movements are habitual, rare plants in widely scattered locations may benefit from euglossine pollination services. Here we report the first successful use of micro Radio Telemetry to track the movement of an insect pollinator in a complex and forested environment. Our results indicate that individual male orchid bees (Exaerete frontalis) habitually use large rainforest areas (at least 42–115 ha) on a daily basis. Aerial Telemetry located individuals up to 5 km away from their core areas, and bees were often stationary, for variable periods, between flights to successive localities. These data suggest a higher degree of site fidelity than what may be expected in a free living male bee, and has implications for our understanding of biological activity patterns and the evolution of forest pollinators.

Christian Bauer - One of the best experts on this subject based on the ideXlab platform.

  • Reaction of common carp (Cyprinus carpio, L.) to oxygen deficiency in winter as an example for the suitability of Radio Telemetry for monitoring the reaction of fish to stress factors in pond aquaculture
    Aquaculture Research, 2006
    Co-Authors: Christian Bauer, Gunther Schlott
    Abstract:

    The reaction of common carp (Cyprinus carpio L.) in an ice- and snow-covered pond to depletion of dissolved oxygen (DO) in winter was recorded using Radio Telemetry. The carp moved from the deeper parts of the pond to the shallow areas near the tributary in search of better oxygenated water. Evidence was found that feeding occurred until December but ceased with the oxygen crisis. After the carp farmer started aeration to improve the oxygen supply, carp returned towards the deeper parts of the pond. The gross activity was significantly correlated with DO (P 0.05). The clear documentation of the carp's reaction to oxygen depletion suggests, that Radio Telemetry may be useful for investigating the effects of various stress factors on fish in pond aquaculture.

  • overwintering of farmed common carp cyprinus carpio l in the ponds of a central european aquaculture facility measurement of activity by Radio Telemetry
    Aquaculture, 2004
    Co-Authors: Christian Bauer, Gunther Schlott
    Abstract:

    Abstract In the aquaculture of farmed common carp ( Cyprinus carpio L.) in Central Europe, it is believed that carp overwinter motionless and without feeding at the bottom of the ponds. However, only a few studies have investigated the behaviour of carp in winter, and data on the overwintering of carp in ponds are rare. This paper presents some new data on the activity of overwintering farmed common carp in Central European aquaculture. Altogether, 14 carp were equipped with surgically implanted Radio Telemetry transmitters and their activity was investigated by positional tracking in a pond (2.2 ha) during the winter seasons of 1999/2000, 2000/2001 and 2001/2002. Low weight loss, WL, and good condition factor, K , suggested that overwintering was successful (WL max.=3.8%, K =1.84–2.33). The carp were found to be relatively active in winter. The mean relative distances between the estimated fish positions on two consecutive tracking sessions ranged from 27.6 to 67.9 m. These activities correlated positively with water temperature in two winter seasons ( p