Publications

temporally patterned sound pulse trains affect intensity and frequency sensitivity of inferior collicular neurons of the big brown bat, eptesicus fuscus.	this study examined the effect of temporally patterned pulse trains on intensity and frequency sensitivity of inferior collicular neurons of the big brown bat, eptesicus fuscus. intensity sensitivity of inferior collicular neurons was expressed by the dynamic range and slope of rate-intensity functions. inferior collicular neurons with non-monotonic rate-intensity functions have smaller dynamic ranges and larger slopes than neurons with monotonic or saturated rate-intensity functions. intensity ...	2001	11763959
gabaergic and glycinergic neural inhibition in excitatory frequency tuning of bat inferior collicular neurons.	this study examined the effect of gabaergic and glycinergic inhibition on excitatory frequency tuning curves (ftcs) of inferior collicular (ic) neurons of the big brown bat, eptesicus fuscus. the excitatory ftcs of 70 ic neurons were either v-shaped (57, 81%), closed (11, 16%), or double-peaked (2, 3%). by means of a two-tone stimulation paradigm, inhibitory ftcs were obtained at one frequency flank only (low-frequency flank: 11, 16%; high-frequency flank: 7, 10%), at both frequency flanks (36, ...	2001	11715077
frequency discrimination threshold at search call frequencies in the echolocating bat, eptesicus fuscus.	while searching for prey in open spaces, epteisicus fuscus emits long-duration, downward frequency-modulated calls which cover a frequency band of about 28-22 khz. in the ascending auditory pathways of e. fuscus, neurons tuned to these search call frequencies are characterised by a remarkably high frequency selectivity and very sensitive absolute thresholds. we investigated whether this narrow tuning is reflected in an exceptional psychoacoustic frequency discrimination ability. the average freq ...	2001	11467501
effects of acetylcholine and atropine on plasticity of central auditory neurons caused by conditioning in bats.	in the big brown bat (eptesicus fuscus), conditioning with acoustic stimuli followed by electric leg-stimulation causes shifts in frequency-tuning curves and best frequencies (hereafter bf shifts) of collicular and cortical neurons, i.e., reorganization of the cochleotopic (frequency) maps in the inferior colliculus (ic) and auditory cortex (ac). the collicular bf shift recovers 180 min after the conditioning, but the cortical bf shift lasts longer than 26 h. the collicular bf shift is not cause ...	2001	11431503
a computational sensorimotor model of bat echolocation.	a computational sensorimotor model of target capture behavior by the echolocating bat, eptesicus fuscus, was developed to understand the detection, localization, tracking, and interception of insect prey in a biological sonar system. this model incorporated acoustics, target localization processes, flight aerodynamics, and target capture planning to produce model trajectories replicating those observed in behavioral insect capture trials. estimates of target range were based on echo delay, azimu ...	2001	11519584
medial superior olive of the big brown bat: neuronal responses to pure tones, amplitude modulations, and pulse trains.	the structure and function of the medial superior olive (mso) is highly variable among mammals. in species with large heads and low-frequency hearing, mso is adapted for processing interaural time differences. in some species with small heads and high-frequency hearing, the mso is greatly reduced in size; in others, including those echolocating bats that have been examined, the mso is large. moreover, the mso of bats appears to have undergone different functional specializations depending on the ...	2001	11698513
type i external skeletal fixation of radial fractures in microchiropterans.	an adult male big brown bat (eptesicus fuscus) and an adult female hoary bat (lasiurus cinereus) were presented with open transverse middiaphyseal left radial fractures. initial repair was attempted by intramedullary pinning. when the fractures did not heal, intramedullary pins were removed and type i external skeletal fixators were placed. the fractures healed, and the big brown bat regained normal flight but the hoary bat did not.	2001	12785704
food chain aspects of chlordane poisoning in birds and bats.	we have observed recurring chlordane poisonings of large numbers of common grackles (quiscalus quiscula), european starlings (sturnus vulgaris), and american robins (turdus migratorius) at suburban roosts in new jersey during the month of july. this paper describes aspects of the food chain uptake of chlordane that account for the periodicity of these poisonings. chlordane concentrations ranged from < 0.02 to 20.3 microg/g wet weight in 11 soil samples collected from residential lawns and a golf ...	2001	11243332
exposure of hooded capuchin monkeys (cebus apella cay) to a rabid bat at a zoological park.	on 27 may 1999, a big brown bat (eptesicus fuscus) was discovered on an island exhibit at the denver zoo that contained a troop of 15 hooded capuchin monkeys (cebus apella cay). the monkeys were attacking the bat when it was discovered. the bat was collected and humanely euthanatized without direct handling and submitted to the colorado department of public health and environment virology laboratory for rabies evaluation. the monkeys had not been vaccinated against rabies virus. the next day, th ...	2001	12790408
molecular evolution of leptin.	leptin, a hormone produced mainly by adipocytes, is involved in the regulation of food intake, metabolism, and reproduction. the objective of this study was to determine the evolutionary relationships of leptin genes. partial nucleotide sequences of leptin were cloned and sequenced from six mammalian species: large hairy armadillo (chaetophractus villosus), rabbit (oryctolagus cuniculus), big brown bat (eptesicus fuscus) [corrected], striped skunk (mephitis mephitis), raccoon (procyon lotor), an ...	2001	11703084
antigenic and genetic divergence of rabies viruses from bat species indigenous to canada.	antigenic characterisation of over 350 chiropteran rabies viruses of the americas, especially from species reported rabid in canada, distinguished 13 viral types. in close accord with this classification, nucleotide sequencing of representative isolates, at both the n and g loci, identified four principal phylogenetic groups (i-iv), sub-groups of which circulated in particular bat species. amongst the north american bat viruses, there was a notable division between group i specimens associated w ...	2001	11226582
bat ectoparasites from the trans-pecos region of texas, including notes from big bend national park.	ectoparasites of 13 species of molossid, mormoopid, and vespertilionid bats from the trans-pecos region of texas were studied, as follows: antrozous pallidus (leconte), corynorhinus townsendii (cooper), eptesicus fuscus (palisot de beauvois), lasiurus cinereus (palisot de beauvois), mormoops megalophylla (peters), myotis thysanodes g. s. miller, myotis velifer (j. a. allen), myotis volans (h. allen), myotis yumanensis (h. allen), nyctinomops femorosaccus (merriam), nyctinomops macrotis (gray), p ...	2001	11372965
uptake of dietary pcb by pregnant big brown bats (eptesicus fuscus) and their fetuses.		2001	98190
tick (acari) infestations of bats in new mexico.	a total of 278 bats belonging to 16 species was examined for ticks from various sites in new mexico from 1994 to 1998. seven species of bats were parasitized by ticks: larvae of ornithodoros kelleyi cooley & kohls, ornithodoros rossi kohls, sonenshine & clifford (argasidae), or both. both species of ticks are reported from new mexico for the first time. infestation prevalences for parasitized bats ranged from 2 to 25% on different host species for o. kelleyi and from 7 to 25% for o. rossi. the p ...	2001	11476346
sound localization in a new-world frugivorous bat, artibeus jamaicensis: acuity, use of binaural cues, and relationship to vision.	passive sound-localization acuity and its relationship to vision were determined for the echolocating jamaican fruit bat (artibeus jamaicensis). a conditioned avoidance procedure was used in which the animals drank fruit juice from a spout in the presence of sounds from their right, but suppressed their behavior, breaking contact with the spout, whenever a sound came from their left, thereby avoiding a mild shock. the mean minimum audible angle for three bats for a 100-ms noise burst was 10 degr ...	2001	11206172
auditory scene analysis by echolocation in bats.	echolocating bats transmit ultrasonic vocalizations and use information contained in the reflected sounds to analyze the auditory scene. auditory scene analysis, a phenomenon that applies broadly to all hearing vertebrates, involves the grouping and segregation of sounds to perceptually organize information about auditory objects. the perceptual organization of sound is influenced by the spectral and temporal characteristics of acoustic signals. in the case of the echolocating bat, its active co ...	2001	11681397
the role of gabaergic inhibition in shaping directional selectivity of bat inferior collicular neurons determined with temporally patterned pulse trains.	this study examined the role of gabaergic inhibition in shaping directional selectivity of neurons in the inferior colliculus of the big brown bat, eptesicus fuscus. when determined with temporally patterned pulse trains at different pulse repetition rates, 93 inferior colliculus neurons displayed three types of directional selectivity curves. a directionally selective curve always showed a maximum to a certain azimuthal angle (the best angle). a hemifield curve showed a maximum to a range of co ...	2002	12466957
transformation of external-ear spectral cues into perceived delays by the big brown bat, eptesicus fuscus.	the external-ear transfer function for big brown bats (eptesicus fuscus) contains two prominent notches that vary from 30 to 55 khz and from 70 to 100 khz, respectively, as sound-source elevation moves from -40 to +10 degrees. these notches resemble a higher-frequency version of external-ear cues for vertical localization in humans and other mammals. however, they also resemble interference notches created in echoes when reflected sounds overlap at short time separations of 30-50 micros. psychop ...	2002	12083212
the effect of sound duration on rate-amplitude functions of inferior collicular neurons in the big brown bat, eptesicus fuscus.	during echolocation, the amplitude and duration of echo pulses of the big brown bat, eptesicus fuscus, covary throughout the entire course of hunting. the purpose of this study was to examine if variation in sound duration might affect the amplitude selectivity of inferior collicular (ic) neurons of this bat species under free-field stimulation conditions. a family of rate-amplitude functions of each ic neuron was obtained with different sound durations. the effect of sound duration on the neuro ...	2002	12062764
selectivity for echo spectral interference and delay in the auditory cortex of the big brown bat eptesicus fuscus.	the acoustic environment for an echolocating bat can contain multiple objects that reflect echoes so closely separated in time that they are almost completely overlapping. this results in a single echo with a spectrum characterized by deep notches due to interference. the object of this study was to document the possible selectivity, or lack thereof, of auditory neurons to the temporal separation of biosonar signals on a coarse (ms) and fine (micros) temporal scale. we recorded single-unit activ ...	2002	12037185
the effect of two-tone stimulation on responses of two simultaneously recorded neurons in the inferior colliculus of the big brown bat, eptesicus fuscus.	this study examined auditory responses of two simultaneously recorded neurons in the central nucleus of bat inferior colliculus (ic) under two-tone stimulation conditions. we specifically examined how a sound within the excitatory frequency tuning curve (ftc) of one ic neuron might affect responses of the other ic neuron in amplitude and frequency domains. under this specific two-tone stimulation condition, responses of 82% neurons were suppressed and their excitatory ftcs sharpened. responses o ...	2002	12117516
interaction between excitation and inhibition affects frequency tuning curve, response size and latency of neurons in the auditory cortex of the big brown bat, eptesicus fuscus.	neurons in the auditory cortex (ac) receive convergent excitatory and inhibitory inputs from the lower auditory nuclei. interaction between these two opposing inputs shapes different response properties of ac neurons. in this study, we examined how this interaction might affect the frequency tuning curves (ftcs), number of impulses and latency of ac neurons in the big brown bat, eptesicus fuscus, using a probe (excitatory tone) and a masker (inhibitory tone) under different stimulation condition ...	2002	12433418
gabaergic inhibition contributes to pulse repetition rate-dependent frequency selectivity in the inferior colliculus of the big brown bat, eptesicus fuscus.	this study examined the effect of bicuculline application on sharpness of frequency tuning curves (ftcs) of bat inferior collicular neurons plotted under three different pulse repetition rates (prrs) of 10, 30 and 90 pulses per second. the sharpness of ftcs of collicular neurons, which was expressed in q(n) (q(10), q(20), q(30)) and bandwidths (90, 75 and 50% of the maximal response at the best frequency), improved with increasing prr. however, this prr-dependent frequency selectivity of collicu ...	2002	12383969
interaction of excitation and inhibition in inferior collicular neurons of the big brown bat, eptesicus fuscus.	neurons in the inferior colliculus (ic) of the midbrain receive convergent excitatory and inhibitory inputs from both lower and higher auditory nuclei. interaction of these two opposing inputs shapes different response properties of ic neurons. in this study, we examined this interaction of excitation and inhibition in ic neurons using a probe (excitatory pulse) and a masker (inhibitory pulse) under different stimulation conditions. inhibition of probe-elicited responses by a masker, i.e. maskin ...	2002	12121747
potential use of chemical cues for colony-mate recognition in the big brown bat, eptesicus fuscus.	bats should benefit from recognition of their roost-mates when colonies form stable social units that persist over time. we used y-maze experiments and gas chromatography-olfactometry (gc-o) to evaluate whether female big brown bats eptesicus fuscus (chiroptera: vespertilionidae) use chemical cues to distinguish among conspecifics. in dual-choice y-maze experiments, females chose the scent of another female from their own roost over a conspecific female from a different roost in a majority of tr ...	2002	12035929
orienting responses and vocalizations produced by microstimulation in the superior colliculus of the echolocating bat, eptesicus fuscus.	an echolocating bat actively controls the spatial acoustic information that drives its behavior by directing its head and ears and by modulating the spectro-temporal structure of its outgoing sonar emissions. the superior colliculus may function in the coordination of these orienting components of the bat's echolocation system. to test this hypothesis, chemical and electrical microstimulation experiments were carried out in the superior colliculus of the echolocating bat, eptesicus fuscus, a spe ...	2002	11919691
augmentation of plasticity of the central auditory system by the basal forebrain and/or somatosensory cortex.	auditory conditioning (associative learning) or focal electric stimulation of the primary auditory cortex (ac) evokes reorganization (plasticity) of the cochleotopic (frequency) map of the inferior colliculus (ic) as well as that of the ac. the reorganization results from shifts in the best frequencies (bfs) and frequency-tuning curves of single neurons. since the importance of the cholinergic basal forebrain for cortical plasticity and the importance of the somatosensory cortex and the corticof ...	2003	12522162
auditory encoding during the last moment of a moth's life.	the simple auditory system of noctuoid moths has long been a model for anti-predator studies in neuroethology, although these ears have rarely been experimentally stimulated by the sounds they would encounter from naturally attacking bats. we exposed the ears of five noctuoid moth species to the pre-recorded echolocation calls of an attacking bat (eptesicus fuscus) to observe the acoustic encoding of the receptors at this critical time in their defensive behaviour. the b cell is a non-tympanal r ...	2003	12477898
expression of the kv1.1 ion channel subunit in the auditory brainstem of the big brown bat, eptesicus fuscus.	voltage-gated potassium channels play an important role in shaping membrane properties that underlie neurons' discharge patterns and the ways in which they transform their input. in the auditory system, low threshold potassium currents such as those created by kv1.1 subunits contribute to precise phaselocking and to transient onset responses that provide time markers for temporal features of sounds. the purpose of the present study was to compare information about the distribution of neurons exp ...	2003	12761827
the effect of bicuculline application on azimuth-dependent recovery cycle of inferior collicular neurons of the big brown bat, eptesicus fuscus.	the recovery cycle of auditory neurons is an important neuronal property, which determines a neuron's ability to respond to pairs of sounds presented at short inter-sound intervals. this property is particularly important for bats, which rely upon analysis of returning echoes to extract the information about targets after emission of intense orientation sounds. because target direction often changes throughout the course of hunting, the changing echo direction may affect the recovery cycle and t ...	2003	12729962
time-frequency model for echo-delay resolution in wideband biosonar.	a time/frequency model of the bat's auditory system was developed to examine the basis for the fine (approximately 2 micros) echo-delay resolution of big brown bats (eptesicus fuscus), and its performance at resolving closely spaced fm sonar echoes in the bat's 20-100-khz band at different signal-to-noise ratios was computed. the model uses parallel bandpass filters spaced over this band to generate envelopes that individually can have much lower bandwidth than the bat's ultrasonic sonar sounds ...	2003	12703724
temporal masking reveals properties of sound-evoked inhibition in duration-tuned neurons of the inferior colliculus.	the inferior colliculus (ic) is the first place in the central auditory pathway where duration-selective neurons are found. previous neuropharmacological and electrophysiological studies have shown that they are created there and have led to a conceptual model in which excitatory and inhibitory inputs are offset in time so that the cell fires only when sound duration is such that onset- and offset-evoked excitation coincide; the response is suppressed by inhibition at other durations. we tested ...	2003	12684492
corticofugal modulation of amplitude domain processing in the midbrain of the big brown bat, eptesicus fuscus.	recent studies have shown that the corticofugal system systematically modulates and improves subcortical signal processing in the frequency, time and spatial domains. the present study examined corticofugal modulation of amplitude sensitivity of 113 corticofugally inhibited neurons in the central nucleus of the inferior colliculus (ic) of the big brown bat, eptesicus fuscus. cortical electrical stimulation decreased the number of impulses and increased the response latency of these neurons. they ...	2003	14553907
gabaergic inhibition and the effect of sound direction on rate-intensity functions of inferior collicular neurons of the big brown bat, eptesicus fuscus.	gabaergic inhibition shapes many auditory response properties of neurons in the inferior colliculus of the big brown bat, eptesicus fuscus. this study examined the role of gabaergic inhibition on direction-dependent rate-intensity functions of bat inferior collicular neurons. when plotted at three sound directions (60 degrees contralateral, 0 degrees and 60 degrees ipsilateral relative to recording site), most collicular neurons had nonmonotonic and saturated rate-intensity functions at 60 degre ...	2003	12974299
the sonar beam pattern of a flying bat as it tracks tethered insects.	this paper describes measurements of the sonar beam pattern of flying echolocating bats, eptesicus fuscus, performing various insect capture tasks in a large laboratory flight room. the beam pattern is deduced using the signal intensity across a linear array of microphones. the positions of the bat and insect prey are obtained by stereoscopic reconstruction from two camera views. results are reported in the form of beam-pattern plots and estimated direction of the beam axis. the bat centers its ...	2003	12942989
echo delay versus spectral cues for temporal hyperacuity in the big brown bat, eptesicus fuscus.	big brown bats can discriminate between echoes that alternate in delay (jitter) by as little as 10-15 ns and echoes that are stationary in delay. this delay hyperacuity seems so extreme that it has been rejected in favor of an explanation in terms of artifacts in echoes, most likely spectral in nature, that presumably are correlated with delay. using different combinations of digital, analog, and cable delays, we dissociated the overall delay of jittering echoes from the size of the analog compo ...	2003	12879356
defining torpor in free-ranging bats: experimental evaluation of external temperature-sensitive radiotransmitters and the concept of active temperature.	a variety of definitions involving body temperature (tb), metabolic rate and behavior have been used to define torpor in mammals and birds. this problem is confounded in some studies of free-ranging animals that employ only skin temperature (tsk), a measure that approximates but may not precisely reflect tb. we assess the accuracy of tsk in the context of a recent definition for torpor called active temperature. we compared the active temperatures of individual big brown bats (eptesicus fuscus), ...	2003	12764630
ectoparasite associations of bats from central pennsylvania.	between april and october 1997, 689 bats representing seven species were captured at pennsylvania's canoe creek state park. each bat was sampled for ectoparasitic arthropods, and four species were collected from 13.2% of the host individuals. ectoparasites include the bat flea myodopsylla insignis (rothschild), the wing mite spinturnix americanus (banks), the bed bug cimex adjunctus barber, and the soft tick ornithodoros kelleyi cooley & kohls. prevalence, relative density, and mean intensity we ...	2003	14765658
comparative analysis of expression and secretion of placental leptin in mammals.	increased plasma level of leptin appears to be a ubiquitous feature of pregnant mammals. the mechanisms by which leptin levels are increased may be species specific, however, with some species upregulating adipose leptin production and others expressing leptin in the placenta. placental leptin expression was examined in representative species of the two most abundant mammalian orders, rodentia and chiroptera, and in cultured human choriocarcinoma (bewo) cells. leptin mrna was expressed in bewo c ...	2003	12702488
evaluation of an auditory model for echo delay accuracy in wideband biosonar.	in a psychophysical task with echoes that jitter in delay, big brown bats can detect changes as small as 10-20 ns at an echo signal-to-noise ratio of approximately 49 db and 40 ns at approximately 36 db. this performance is possible to achieve with ideal coherent processing of the wideband echoes, but it is widely assumed that the bat's peripheral auditory system is incapable of encoding signal waveforms to represent delay with the requisite precision or phase at ultrasonic frequencies. this ass ...	2003	14514218
development of reorganization of the auditory cortex caused by fear conditioning: effect of atropine.	reorganization of the frequency map in the central auditory system is based on shifts in the best frequencies (bfs; hereafter, bf shifts), together with the frequency-response curves, of auditory neurons. in the big brown bat, conditioning with acoustic stimulation followed by electric leg-stimulation causes bf shifts of collicular and cortical neurons. the collicular bf shift develops quickly and is short term, whereas the cortical bf shift develops slowly and is long term. the acetycholine lev ...	2003	12966181
binaural interaction in the inferior colliculus of the big brown bat, eptesicus fuscus.	binaural interaction plays an important role in shaping response properties of central auditory neurons. using single unit recording and iontophoresis, we examined frequency tuning curves (ftcs), interaural intensity difference (iid) curves, and rate-intensity functions of inferior collicular (ic) neurons of the big brown bat, eptesicus fuscus, under closed system or free field stimulation conditions. we isolated 46 ei (excitation-inhibition), 24 eo (monaural excitation) and 6 ee (excitation-exc ...	2003	12618322
lateral inhibition for center-surround reorganization of the frequency map of bat auditory cortex.	repetitive acoustic stimulation, auditory fear conditioning, and focal electric stimulation of the auditory cortex (ac) each evoke the reorganization of the central auditory system. our current study of the big brown bat indicates that focal electric stimulation of the ac evokes center-surround reorganization of the frequency map of the ac. in the center, the neuron's best frequencies (bfs), together with their frequency-tuning curves, shift toward the bfs of electrically stimulated cortical neu ...	2004	15548634
west nile virus antibodies in bats from new jersey and new york.	eighty-three serum samples were obtained from big brown (eptesicus fuscus), little brown (myotis lucifugus), and northern long-eared (myotis septentriotalis) bats (chiroptera: vespertilionidae), from new jersey and new york (usa) between july and october 2002. samples were analyzed for neutralizing antibodies to west nile virus (wnv) and st. louis encephalitis (sle) virus. one little brown bat and one northern long-eared bat tested positive for wnv neutralizing antibodies. no bats had antibodies ...	2004	15362837
rabies in a captive colony of big brown bats (eptesicus fuscus).	our research has focused on the ecology of commensal populations of big brown bats (eptesicus fuscus) in fort collins, colorado (usa), in relation to rabies virus (rv) transmission. we captured 35 big brown bats (eptesicus fuscus) in late summer 2001 and held them captive for 4.8 mo. the bats were initially placed in an indoor cage for 1 mo then segregated into groups of two to six per cage. two of the bats succumbed to rabies virus (rv) within the first month of capture. despite group housing, ...	2004	15465706
experimental feeding of dde and pcb to female big brown bats (eptesicus fuscus).	twenty-two female big brown bats (eptesicus fuscus) were collected in a house attic in montgomery county, maryland. seventeen were fed mealworms (tenebrio molitor larvae) that contained 166 ppm dde; the other five were fed uncontaminated mealworms. after 54 days of feeding, six dosed bats were frozen and the remaining 16 were starved to death. in a second experiment, 21 female big brown bats were collected in a house attic in prince georges county, maryland. sixteen were fed mealworms that conta ...	2004	404435
characterization of an ecori family of satellite dna from two species of the genus eptesicus (vespertilionidae; chiroptera).	we have cloned and sequenced a 321 bp band of repetitive dna from eptesicus fuscus and e. serotinus observed after gel electrophoresis of ecori digested genomic dna in both species. southern blot analysis of genomic dna (from both species) digested with the same enzyme showed the existence of a ladder pattern indicating that the repetitive dna is arrayed in tandem. the repetitive sequences have a monomer unit of 321 bp which is composed of two subunits of 160 bp, suggested by the existence of a ...	2004	15609553
a numerical study of the role of the tragus in the big brown bat.	a comprehensive characterization of the spatial sensitivity of an outer ear from a big brown bat (eptesicus fuscus) has been obtained using numerical methods and visualization techniques. pinna shape information was acquired through x-ray microtomography. it was used to set up a finite-element model of diffraction from which directivities were predicted by virtue of forward wave-field projections based on a kirchhoff integral formulation. digital shape manipulation was used to study the role of ...	2004	15658720
the bat head-related transfer function reveals binaural cues for sound localization in azimuth and elevation.	directional properties of the sound transformation at the ear of four intact echolocating bats, eptesicus fuscus, were investigated via measurements of the head-related transfer function (hrtf). contributions of external ear structures to directional features of the transfer functions were examined by remeasuring the hrtf in the absence of the pinna and tragus. the investigation mainly focused on the interactions between the spatial and the spectral features in the bat hrtf. the pinna provides g ...	2004	15658710
azimuth-dependent recovery cycle affects directional selectivity of bat inferior collicular neurons determined with sound pulses within a pulse train.	in our previous study, we have shown that the recovery cycle of most neurons in the inferior colliculus (ic) of the big brown bat, eptesicus fuscus, is typically longer at ipsilateral azimuth than at contralateral azimuth under free-field stimulation conditions. the present study is to test the hypothesis that this azimuth-dependent recovery cycle may contribute to the variation of directional selectivity of ic neurons with sequential presented sound pulses within a pulse train. a 300-ms pulse t ...	2004	15306265
interaction of vestibular, echolocation, and visual modalities guiding flight by the big brown bat, eptesicus fuscus.	the big brown bat (eptesicus fuscus) is an aerial-feeding insectivorous species that relies on echolocation to avoid obstacles and to detect flying insects. spatial perception in the dark using echolocation challenges the vestibular system to function without substantial visual input for orientation. ir thermal video recordings show the complexity of bat flights in the field and suggest a highly dynamic role for the vestibular system in orientation and flight control. to examine this role, we ca ...	2004	15156093
delay accuracy in bat sonar is related to the reciprocal of normalized echo bandwidth, or q.	big brown bats (eptesicus fuscus) emit wideband, frequency-modulated biosonar sounds and perceive the distance to objects from the delay of echoes. bats remember delays and patterns of delay from one broadcast to the next, and they may rely on delays to perceive target scenes. while emitting a series of broadcasts, they can detect very small changes in delay based on their estimates of delay for successive echoes, which are derived from an auditory time/frequency representation of frequency-modu ...	2004	14990794
relation between intrinsic connections and isofrequency contours in the inferior colliculus of the big brown bat, eptesicus fuscus.	information processing in the inferior colliculus depends on interactions between ascending pathways and intrinsic circuitry, both of which exist within a functional tonotopic organization. to determine how local projections of neurons in the inferior colliculus are related to tonotopy, we placed a small iontophoretic injection of biodextran amine at a physiologically characterized location in the inferior colliculus. we then used electrophysiological recording to place a grid of small deposits ...	2005	16344159
echolocating bats can use acoustic landmarks for spatial orientation.	we investigated the echolocating bat's use of an acoustic landmark for orientation in a complex environment with no visual information. three bats of the species eptesicus fuscus were trained to fly through a hole in a mist net to receive a food reward on the other side. in all experiments, the vocal behavior of the bats was recorded simultaneously using a high-speed video recording system, allowing for a 3d reconstruction of the flight path. we ran three types of experiments, with different spa ...	2005	16339860
target representation of naturalistic echolocation sequences in single unit responses from the inferior colliculus of big brown bats.	echolocating big brown bats (eptesicus fuscus) emit trains of frequency-modulated (fm) biosonar signals whose duration, repetition rate, and sweep structure change systematically during interception of prey. when stimulated with a 2.5-s sequence of 54 fm pulse-echo pairs that mimic sounds received during search, approach, and terminal stages of pursuit, single neurons (n = 116) in the bat's inferior colliculus (ic) register the occurrence of a pulse or echo with an average of < 1 spike/sound. in ...	2005	16334705
corticofugal modulation of directional sensitivity in the midbrain of the big brown bat, eptesicus fuscus.	in our recent study of corticofugal modulation of collicular amplitude sensitivity of the big brown bat, eptesicus fuscus, we suggested that the corticofugal modulation is based upon the best frequency (bf) differences and the relative amplitude sensitivity difference between collicular (ic) and cortical (ac) neurons but not the absolute amplitude sensitivity of ic and ac neurons. to show that corticofugal modulation is systematic and multiparametric, we studied corticofugal modulation of direct ...	2005	15855045
sound strategy: acoustic aposematism in the bat-tiger moth arms race.	the night sky is the venue for an ancient arms race. insectivorous bats with their ultrasonic sonar exert an enormous selective pressure on nocturnal insects. in response insects have evolved the ability to hear bat cries, to evade their hunting maneuvers, and some, the tiger moths (arctiidae), to utter an ultrasonic reply. we here determine what it is that tiger moths "say" to bats. we chose four species of arctiid moths, cycnia tenera, euchaetes egle, utetheisa ornatrix, and apantesis nais, th ...	2005	15772807
duration selectivity of neurons in the inferior colliculus of the big brown bat: tolerance to changes in sound level.	at and above the level of the inferior colliculus (ic), some neurons respond maximally to a limited range of sound durations, with little or no excitatory response to durations outside of this range. such neurons have been termed "duration tuned" or "duration selective." in this study we examined the effects of varying signal amplitude on best duration, width of tuning, and first spike latency of duration tuned neurons in the ic of the big brown bat, eptesicus fuscus. response areas as a functio ...	2005	15888527
effects of backward masking on the responses of the inferior collicular neurons in the big brown bat, eptesicus fuscus.	temporal features of sound convey information vital for behaviors as diverse as speech recognition by human and echolocation by bats. however, auditory stimuli presented in temporal proximity might interfere with each other. although much progress has been made in the description of this phenomenon from psychophysical studies, the neural mechanism responsible for its formation at central auditory structures especially at the inferior colliculus (ic), a midbrain auditory nucleus which practically ...	2005	15830109
a need for standardized rabies-virus diagnostic procedures: effect of cover-glass mountant on the reliability of antigen detection by the fluorescent antibody test.	the direct fluorescent antibody test is a sensitive and specific procedure used in the routine diagnosis of rabies. however, given the critical role of the rabies diagnostic laboratory in patient management and public health decision-making, the use of a standardized national rabies diagnostic procedure is highly recommended. seemingly small variations in test procedures may have dramatic effects on sensitivity. for example, two independent reports of diminished staining performance of two lots ...	2005	15896406
experimental and natural infection of north american bats with west nile virus.	big brown (eptesicus fuscus) and mexican free-tailed (tadarida brasiliensis) bats were inoculated with the new york 99 strain of west nile virus to assess their potential to serve as amplifying hosts and determine the clinical effect of infection. groups of three or four bats were bled at daily intervals between 1 and 6 days after inoculation to determine the pattern of viremia. beginning 2 days after inoculation, virus was isolated each day from one or more e. fuscus bats, in titers ranging fro ...	2005	16103624
corticofugal feedback for auditory midbrain plasticity elicited by tones and electrical stimulation of basal forebrain in mice.	the auditory cortex (ac) is the major origin of descending auditory projections and is one of the targets of the cholinergic basal forebrain, nucleus basalis (nb). in the big brown bat, cortical activation evokes frequency-specific plasticity in the inferior colliculus and the nb augments this collicular plasticity. to examine whether cortical descending function and nb contributions to collicular plasticity are different between the bat and mouse and to extend the findings in the bat, we induce ...	2005	16115210
neorickettsia risticii is vertically transmitted in the trematode acanthatrium oregonense and horizontally transmitted to bats.	potomac horse fever is known to be transmitted through the ingestion of caddisflies parasitized with neorickettsia (formerly ehrlichia) risticii-infected metacercaria. however, the species of trematode involved and how n. risticii is maintained in nature are unknown. in this study, gravid trematodes were recovered from the intestines of 12 out of 15 eptesicus fuscus big brown bats and eight out of nine myotis lucifugus little brown bats from various sites in pennsylvania, usa. trematode specimen ...	2005	15658987
genetic divergence of rabies viruses from bat species of colorado, usa.	molecular epidemiological studies have linked many cryptic human rabies cases in the united states with exposure to rabies virus (rv) variants associated with insectivorous bats. in colorado, bats accounted for 98% of all reported animal rabies cases between 1977 and 1996. the genetic divergence of rv was investigated in bat and terrestrial animal specimens that were submitted for rabies diagnosis to the colorado department of public health and environment (cdphe), colorado, usa. rv isolates fro ...	2005	16417429
anesthesia and blood sampling of wild big brown bats (eptesicus fuscus) with an assessment of impacts on survival.	we anesthetized and blood sampled wild big brown bats (eptesicus fuscus) in fort collins, colorado (usa) in 2001 and 2002 and assessed effects on survival. inhalant anesthesia was delivered into a specially designed restraint and inhalation capsule that minimized handling and bite exposures. bats were immobilized an average of 9.1+/-5.1 (sd) min (range 1-71, n=876); blood sample volumes averaged 58+/-12 microl (range 13-126, n=718). we randomly selected control (subject to multiple procedures be ...	2005	15827214
evolutionary timescale of rabies virus adaptation to north american bats inferred from the substitution rate of the nucleoprotein gene.	throughout north america, rabies virus (rv) is endemic in bats. distinct rv variants exist that are closely associated with infection of individual host species, such that there is little or no sustained spillover infection away from the primary host. using bayesian methodology, nucleotide substitution rates were estimated from alignments of partial nucleoprotein (n) gene sequences of nine distinct bat rv variants from north america. substitution rates ranged from 2.32 x 10(-4) to 1.38 x 10(-3) ...	2005	15831959
corticofugal feedback for collicular plasticity evoked by electric stimulation of the inferior colliculus.	focal electric stimulation of the auditory cortex, 30-min repetitive acoustic stimulation, and auditory fear conditioning each evoke shifts of the frequency-tuning curves [hereafter, best frequency (bf) shifts] of cortical and collicular neurons. the short-term collicular bf shift is produced by the corticofugal system and primarily depends on the relationship in bf between a recorded collicular and a stimulated cortical neuron or between the bf of a recorded collicular neuron and the frequency ...	2005	16000518
effects of agonists and antagonists of nmda and ach receptors on plasticity of bat auditory system elicited by fear conditioning.	in big brown bats, tone-specific plastic changes [best frequency (bf) shifts] of cortical and collicular neurons can be evoked by auditory fear conditioning, repetitive acoustic stimuli or cortical electric stimulation. it has been shown that acetylcholine (ach) plays an important role in evoking large long-term cortical bf shifts. however, the role of n-methyl-d-aspartate (nmda) receptors in evoking bf shifts has not yet been studied. we found 1) nmda applied to the auditory cortex (ac) or infe ...	2005	16061490
effects of arousal from hibernation and plasma androgen levels on mating behavior in the male big brown bat, eptesicus fuscus.	the effects of arousal from hibernation and presence of plasma androgen on the expression of mating behavior in male big brown bats (eptesicus fuscus) were tested in a captive population exposed to seminatural conditions in central alabama. in the mild winter of 1994-1995, flight cage temperatures never fell below 10 degrees c. bats were never observed to enter sustained (over 2 d) torpor. they were also never observed to mate. unmanipulated, sham-operated, and gonadectomized males and unmanipul ...	2006	9279922
echolocating bats use a nearly time-optimal strategy to intercept prey.	acquisition of food in many animal species depends on the pursuit and capture of moving prey. among modern humans, the pursuit and interception of moving targets plays a central role in a variety of sports, such as tennis, football, frisbee, and baseball. studies of target pursuit in animals, ranging from dragonflies to fish and dogs to humans, have suggested that they all use a constant bearing (cb) strategy to pursue prey or other moving targets. cb is best known as the interception strategy e ...	2006	16605303
a survey for west nile virus in bats from illinois.	a blocking enzyme-linked immunosorbent assay was used to test 97 serum samples from big brown bats (eptesicus fuscus) captured in six counties in illinois between may 2002 and february 2004 for west nile virus (wnv) antibodies. one female big brown bat tested positive for wnv antibodies. samples of kidney, liver, and heart tissue were collected from 312 bats of seven species that were submitted to the illinois (usa) department of public health or the illinois department of agriculture diagnostic ...	2006	16870875
use of artificial roost structures by bats at the indianapolis international airport.	from 1992-1996, 3204 artificial roosts of 9 types were placed in woodlots near indianapolis international airport in an effort to provide habitat for the federally-endangered indiana myotis (myotis sodalis) and to determine the feasibility of using these structures to manage bats in a rapidly developing suburban area. we surveyed these structures at least annually during 1992-1999 and found only northern myotis (myotis septentrionalis) regularly using the structures. four other species were occa ...	2006	16622759
experimental infection of big brown bats (eptesicus fuscus) with eurasian bat lyssaviruses aravan, khujand, and irkut virus.	here we describe the results of experimental infections of captive big brown bats (eptesicus fuscus) with three newly isolated bat lyssaviruses from eurasia (aravan, khujand, and irkut viruses). infection of e. fuscus was moderate (total, 55-75%). there was no evidence of transmission to in-contact cage mates. incubation periods for irkut virus infection were significantly shorter (p < 0.05) than for either aravan or khujand virus infections. in turn, quantification of viral rna by taqman pcr su ...	2006	16705370
serologic survey of eptesicus fuscus from georgia, u.s.a. for rickettsia and borrelia and laboratory transmission of a rickettsia by bat ticks.	bats and their ectoparasites are associated with bacterial agents of unknown pathogenicity. we tested sera from 56 eptesicus fuscus from georgia against borrelia hermsii, orientia tsutsugamushi, rickettsia conorii, and rickettsia rickettsii. we detected antibodies reactive against a relapsing fever borrelia and spotted fever group rickettsia in 3/56 and 1/56 bats, respectively. we attempted to culture bartonella from the blood of these bats but were unsuccessful. in addition, we fed bat ticks, c ...	2006	17249357
threshold minima and maxima in the behavioral audiograms of the bats artibeus jamaicensis and eptesicus fuscus are not produced by cochlear mechanics.	behavioral audiograms of artibeus jamaicensis and eptesicus fuscus are characterized by two threshold minima separated by a threshold maximum at 40 khz, for a. jamaicensis, and 45 khz, for e. fuscus [koay, g., heffner, h.e., heffner r.s., 1997. audiogram of the big brown bat (eptesicus fuscus). hear. res. 105, 202-210; heffner, r.s., koay, g., heffner h.e., 2003. hearing in american leaf-nosed bats. iii: artibeus jamaicensis. hear. res. 184, 113-122.]. to investigate whether these characteristic ...	2006	16434158
a tale of two siblings: multiple paternity in big brown bats (eptesicus fuscus) demonstrated using microsatellite markers.	in many bat species, the opportunity for sperm competition or other mechanisms of post-copulatory paternity biasing is thought to be great, due to the long delay between copulation and fertilization, demonstrated sperm storage capabilities, and observed promiscuity. we present the results of the first study to assess whether litters of big brown bats (eptesicus fuscus) containing dizygotic twins share the same father. we sampled 26 mother-offspring triads from three colonies in indiana and illin ...	2006	16367843
active listening for spatial orientation in a complex auditory scene.	to successfully negotiate a complex environment, an animal must control the timing of motor behaviors in coordination with dynamic sensory information. here, we report on adaptive temporal control of vocal-motor behavior in an echolocating bat, eptesicus fuscus, as it captured tethered insects close to background vegetation. recordings of the bat's sonar vocalizations were synchronized with high-speed video images that were used to reconstruct the bat's three-dimensional flight path and the posi ...	2006	16509770
the role of gabaergic inhibition in shaping duration selectivity of bat inferior collicular neurons determined with temporally patterned sound trains.	a previous study has shown that duration selectivity of neurons in the inferior colliculus (ic) of the big brown bat, eptesicus fuscus becomes sharper with increasing pulse repetition rate (prr). the present study examines the role of gabaergic inhibition in improving duration selectivity of bat ic neurons with prr by means of iontophoretic application of gaba as well as its antagonist, bicuculline. duration selectivity of ic neurons is studied by plotting the duration tuning curves with the num ...	2006	16644156
sampling blood from big brown bats (eptesicus fuscus) in the field with and without anesthesia: impacts on survival.	blood was collected from wild big brown bats (eptesicus fuscus) with and without anesthesia in fort collins, colorado in 2004 to assess the impacts of these procedures on short-term survival and 1-yr return rates. short-term survival and 1-yr return rates after release were passively monitored using pit tag detection hoops placed at selected buildings. comparison of 14-day maximum likelihood survival estimates from bats not bled (142 adult females, 62 volant juveniles), and bats sampled for bloo ...	2006	17255454
navigation: bat orientation using earth's magnetic field.	bats famously orientate at night by echolocation, but this works over only a short range, and little is known about how they navigate over longer distances. here we show that the homing behaviour of eptesicus fuscus, known as the big brown bat, can be altered by artificially shifting the earth's magnetic field, indicating that these bats rely on a magnetic compass to return to their home roost. this finding adds to the impressive array of sensory abilities possessed by this animal for navigation ...	2006	17151656
duration selectivity of bat inferior collicular neurons improves with increasing pulse repetition rate.	insectivorous big brown bats, eptesicus fuscus, progressively increase the pulse repetition rate (prr) throughout the course of hunting. while increasing prr conceivably facilitates bats to extract information about the targets, it also inevitably affects sensitivity of their auditory neurons to pulse parameters. the present study examined the effect of increasing prr on duration selectivity of this bat's inferior collicular (ic) neurons by comparing their impulse-duration functions determined a ...	2006	16900705
variation in body composition of female big brown bats (eptesicus fuscus) during lactation.	most small mammals support the nutritional requirements of milk production by increasing food intake. however, when nutrient intake is low, maternal body reserves may be mobilized to maintain adequate milk output. we examined patterns of body composition, including dry matter, fat, protein, and mineral content in big brown bats, eptesicus fuscus, during lactation. concentrations of fat and phosphorus were markedly lower in lactating mothers during week three of lactation than during the first tw ...	2006	16835744
duration selectivity organization in the inferior colliculus of the big brown bat, eptesicus fuscus.	duration selectivity of auditory neurons plays an important role in sound recognition. previous studies show that gaba-mediated duration selectivity of neurons in the central nucleus of the inferior colliculus (ic) of many animal species behave as band-, short-, long- and all-pass filters to sound duration. the present study examines the organization of duration selectivity of ic neurons of the big brown bat, eptesicus fuscus, in relation to graded spatial distribution of gaba(a) receptors, whic ...	2006	16828465
gaba-mediated echo duration selectivity of inferior collicular neurons of eptesicus fuscus, determined with single pulses and pulse-echo pairs.	when insectivorous bats such as eptesicus fuscus emit ultrasonic signals and analyze the returning echoes to hunt insects, duration selectivity of auditory neurons plays an important role in echo recognition. the success of prey capture indicates that they can effectively encode progressively shortened echo duration throughout the hunting process. the present study examines the echo duration selectivity of neurons in the central nucleus of the bat inferior colliculus (ic) under stimulation condi ...	2006	16738883
gabaergic inhibition modulates intensity sensitivity of temporally patterned pulse trains in the inferior collicular neurons in big brown bats.	the echolocating big brown bats (eptesicus fuscus) emit trains of frequency-modulated (fm) biosonar signals with duration, amplitude, repetition rate, and sweep structure changing systematically during interception of their prey. in the present study, the sound stimuli of temporally patterned pulse trains at three different pulse repetition rates (prrs) were used to mimic the sounds received during search, approach, and terminal stages of echolocation. electrophysiological method was adopted in ...	2007	18157475
factors influencing movement probabilities of big brown bats (eptesicus fuscus) in buildings.	we investigated movements of female big brown bats (eptesicus fuscus) roosting in maternity colonies in buildings in fort collins, colorado (usa), during the summers of 2002, 2003, and 2005. this behavior can be of public health concern where bats that may carry diseases (e.g., rabies) move among buildings occupied by people. we used passive integrated transponders (pit tags) to mark individual bats and hoop pit readers at emergence points to passively monitor the use of building roosts by marke ...	2007	17489265
energy availability influences microclimate selection of hibernating bats.	many species hibernate to conserve energy during periods of low food and water availability. it has long been assumed that the optimal hibernation strategy involves long, deep bouts of torpor that minimize energy expenditure. however, hibernation has ecological (e.g. decreased predator avoidance) and physiological (e.g. sleep deprivation) costs that must be balanced with energy savings; therefore, individuals possessing sufficient energy reserves may reduce their use of deep torpor. we tested th ...	2007	18055623
corticofugal modulation of multi-parametric auditory selectivity in the midbrain of the big brown bat.	corticofugal modulation of sub-cortical auditory selectivity has been shown previously in mammals for frequency, amplitude, time, and direction domains in separate studies. as such, these studies do not show if multi-parametric corticofugal modulation can be mediated through the same sub-cortical neuron. here we specifically studied corticofugal modulation of best frequency (bf), best amplitude (ba), and best azimuth (baz) at the same neuron in the inferior colliculus of the big brown bat, eptes ...	2007	17804577
biosonar signals impinging on the target during interception by big brown bats, eptesicus fuscus.	big brown bats (eptesicus fuscus) were videotaped in the dark with a night-vision lens and infrared illumination while flying repeatedly along the same straight course to seize a tethered mealworm or a small electret microphone used to record biosonar signals impinging on the target. bats emitted frequency-modulated sounds with first to third harmonics covering frequencies from 23 to 105 khz. as the bats neared the target, the first harmonic shifted lower in frequency while the third harmonic st ...	2007	17550198
the role of the external ear in vertical sound localization in the free flying bat, eptesicus fuscus.	the role of the external ear in sonar target localization for prey capture was studied by deflecting the tragus of six big brown bats, eptesicus fuscus. the prey capture performance of the bat dropped significantly in the tragus-deflection condition, compared with baseline, control, and recovery conditions. target localization error occurred in the tragus-deflected bat, and mainly in elevation. the deflection of the tragus did not abolish the prey capture ability of the bat, which suggests that ...	2007	17471736
neurons in the inferior colliculus of the big brown bat show maximal amplitude sensitivity at the best duration.	the big brown bats, eptesicus fuscus, emit ultrasonic signals and analyze the returning echoes in multi-parametric domains to extract target features. the variation of different pulse parameters during hunting predicts that analysis of an echo parameter by bats is inevitably affected by other co-varying echo parameters. in this study, we presented data to show that the bat inferior collicular (ic) neurons have maximal amplitude sensitivity at the best duration (bd). a family of rate-amplitude fu ...	2007	18274162
multiparametric corticofugal modulation of collicular duration-tuned neurons: modulation in the amplitude domain.	the subcortical auditory nuclei contain not only neurons tuned to a specific frequency but also those tuned to multiple parameters characterizing a sound. all these neurons are potentially subject to modulation by descending fibers from the auditory cortex (corticofugal modulation). in the past, we electrically stimulated cortical duration-tuned neurons of the big brown bat, eptesicus fuscus, and found that its collicular duration-tuned neurons were corticofugally modulated in the frequency and ...	2007	17376844
neurophysiological study on sensorimotor control mechanism in superior colliculus of echolocating bat.	this paper investigates the neural processes associated with bat sonar vocal production and their relationship with spatial orientation. the bat's heavy reliance on sound processing is reflected in specializations of auditory and motor neural structures. these specializations were utilized by investigating the mammalian superior colliculus (sc); a midbrain sensory motor nucleus mediating orientating behaviours in mammals, including vocal motor orientating. behavioural and neurophysiological expe ...	2007	17367792
detection of group 1 coronaviruses in bats in north america.	the epidemic of severe acute respiratory syndrome (sars) was caused by a newly emerged coronavirus (sars-cov). bats of several species in southern people's republic of china harbor sars-like covs and may be reservoir hosts for them. to determine whether bats in north america also harbor coronaviruses, we used reverse transcription-pcr to detect coronavirus rna in bats. we found coronavirus rna in 6 of 28 fecal specimens from bats of 2 of 7 species tested. the prevalence of viral rna shedding was ...	2007	18252098
flying big brown bats emit a beam with two lobes in the vertical plane.	the sonar beam of an echolocating bat forms a spatial window restricting the echo information returned from the environment. investigating the shape and orientation of the sonar beam produced by a bat as it flies and performs various behavioral tasks may yield insight into the operation of its sonar system. this paper presents recordings of vertical and horizontal cross sections of the sonar beam produced by eptesicus fuscus (big brown bats) as they fly and pursue prey in a laboratory flight roo ...	2007	18247779
ectoparasites in an urban population of big brown bats (eptesicus fuscus) in colorado.	ectoparasites of an urban population of big brown bats (eptesicus fuscus) in fort collins, colorado, were investigated during summers 2002, 2003, and 2004. eleven species of ectoparasites were found (the macronyssid mite steatonyssus occidentalis, the wing mite spinturnix bakeri, the myobiid mites acanthophthirius caudata and pteracarus aculeus, the chirodiscid mite alabidocarpus eptesicus, the demodicid mite demodex sp., the chigger leptotrombidium myotis, the soft tick carios kelleyi, the batf ...	2007	17626343
temperatures and locations used by hibernating bats, including myotis sodalis (indiana bat), in a limestone mine: implications for conservation and management.	understanding temperatures used by hibernating bats will aid conservation and management efforts for many species. a limestone mine with 71 km of passages, used as a hibernaculum by approximately 30,000 bats, was visited four times during a 6-year period. the mine had been surveyed and mapped; therefore, bats could be precisely located and temperatures (t (s)) of the entire hibernaculum ceiling accurately mapped. it was predicted that bats should hibernate between 5 and 10 degrees c to (1) use t ...	2007	17874161
lack of association between ectoparasite intensities and rabies virus neutralizing antibody seroprevalence in wild big brown bats (eptesicus fuscus), fort collins, colorado.	recently, bat ectoparasites have been demonstrated to harbor pathogens of potential importance to humans. we evaluated antirabies antibody seroprevalence and the presence of ectoparasites in big brown bats (eptesicus fuscus) sampled in 2002 and 2003 in colorado to investigate if an association existed between ectoparasite intensity and exposure to rabies virus (rv). we used logistic regression and akaike's information criteria adjusted for sample size (aicc) in a post-hoc analysis to investigate ...	2007	17979542
rabies in bats from alabama.	data on rabies virus infection in bats that were submitted to the alabama department of public health from 1995-2005 were analyzed. demographic factors, such as species and sex, and temporal aspects, such as yearly and monthly trends, were investigated. thirteen species of bats were submitted, and of those, individuals from seven species were rabid; prevalence was highest in lasiurus borealis and pipistrellus subflavus and lowest in eptesicus fuscus and nycticeius humeralis. there was no differe ...	2007	17495316
response properties and location of neurons selective for sinusoidal frequency modulations in the inferior colliculus of the big brown bat.	most animal vocalizations, including echolocation signals used by bats, contain frequency-modulated (fm) components. previous studies have described a class of neurons in the inferior colliculus (ic) of the big brown bat that respond exclusively to sinusoidally frequency modulated (sfm) signals and fail to respond to pure tones, noise, amplitude-modulated tones, or single fm sweeps. the aims of this study were to further characterize these neurons' response properties and to determine whether th ...	2007	17634338