Open Access. Powered by Scholars. Published by Universities.®

Organisms Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 4 of 4

Full-Text Articles in Organisms

Autonomic Nervous System Reactivity In A Free-Ranging Mammal: Effects Of Dominance Rank And Personality, Elodie F. Briefer, James A. Oxley, Alan G. Mcelligott Sep 2016

Autonomic Nervous System Reactivity In A Free-Ranging Mammal: Effects Of Dominance Rank And Personality, Elodie F. Briefer, James A. Oxley, Alan G. Mcelligott

Elodie Briefer, PhD

Modulation of the autonomic nervous system (ANS) activity allows animals to effectively respond to internal and external stimuli in everyday challenges via changes in, for example, heart and respiration rate. Various factors, ranging from social such as dominance rank to internal such as personality or affective states can impact animal physiology. Our knowledge of the combinatory effects of social and internal factors on ANS basal activity and reactivity, and of the importance that each factor has in determining physiological parameters, is limited, particularly in nonhuman, free-ranging animals. In this study, we tested the effects of dominance rank and personality (assessed …


Characterisation Of Chemosensory Trigeminal Receptors In The Rainbow Trout, Oncorhynchus Mykiss: Responses To Chemical Irritants And Carbon Dioxide, Jessica J. Mettam, Catherine R. Mccrohan, Lynne U. Sneddon Jul 2015

Characterisation Of Chemosensory Trigeminal Receptors In The Rainbow Trout, Oncorhynchus Mykiss: Responses To Chemical Irritants And Carbon Dioxide, Jessica J. Mettam, Catherine R. Mccrohan, Lynne U. Sneddon

Lynne Sneddon, PhD

Trigeminally innervated, mechanically sensitive chemoreceptors (M) were previously identified in rainbow trout, Oncorhynchus mykiss, but it is not known whether these receptors are responsive only to noxious, chemical irritants or have a general chemosensory function. This study aimed to characterise the stimulus–response properties of these receptors in comparison with polymodal nociceptors (P). Both P and M gave similar response profiles to acetic acid concentrations. The electrophysiological properties were similar between the two different afferent types. To determine whether the receptors have a nociceptive function, a range of chemical stimulants was applied to these receptors, including non-noxious stimuli such as ammonium …


Physiological And Behavioural Responses To Noxious Stimuli In The Atlantic Cod (Gadus Morhua), Jared R. Eckroth, Øyvind Aas-Hansen, Lynne U. Sneddon, Helena Bichão, Kjell B. Døving Apr 2015

Physiological And Behavioural Responses To Noxious Stimuli In The Atlantic Cod (Gadus Morhua), Jared R. Eckroth, Øyvind Aas-Hansen, Lynne U. Sneddon, Helena Bichão, Kjell B. Døving

Lynne Sneddon, PhD

In the present study, our aim was to compare physiological and behavioural responses to different noxious stimuli to those of a standardized innocuous stimulus, to possibly identify aversive responses indicative of injury detection in a commercially important marine teleost fish, the Atlantic cod. Individual fish were administered with a noxious stimulus to the lip under short-term general anaesthesia (MS-222). The noxious treatments included injection of 0.1% or 2% acetic acid, 0.005% or 0.1% capsaicin, or piercing the lip with a commercial fishing hook. Counts of opercular beat rate (OBR) at 10, 30, 60, 90 and 120 min and observations of …


Hovering Energetics And Thermal Balance In Anna's Hummingbirds (Calypte Anna), Dennis Evangelista, Maria J. Fernandez, Madalyn S. Berns, Aaron M. Hoover, Robert Dudley Jul 2012

Hovering Energetics And Thermal Balance In Anna's Hummingbirds (Calypte Anna), Dennis Evangelista, Maria J. Fernandez, Madalyn S. Berns, Aaron M. Hoover, Robert Dudley

Aaron M. Hoover

We studied the energetics of hover-feeding Anna's hummingbirds, using three different simultaneous techniques: heat loss as estimated via thermal imaging, metabolic rate as measured at a feeder mask using flow-through respirometry, and aerodynamic power estimated from wingbeat kinematic data. These three methods yielded comparable estimates of power output at ambient air temperatures ranging from 18 degrees to 26 degrees C, whereas heat imbalance at higher air temperatures (up to 34 degrees C) suggested loss by mechanisms other than convection and radiation from the body, such as evaporative cooling and enthalpy rise associated with exhaled air and excreted water and convective …