A novel copy number variant in the murine Cdh23 gene gives rise to profound deafness and vestibular dysfunction.

Hearing loss is the most common congenital sensory deficit worldwide and exhibits high genetic heterogeneity, making molecular diagnoses elusive for most individuals. Detecting novel mutations that contribute to hearing loss is crucial to providing accurate personalized diagnoses, tailored interventions, and improving prognosis. Copy number variants (CNVs) are structural mutations that are understudied, potential contributors to hearing loss.

Scanning efficacy of p-Chips implanted in the wing and leg of the Big Brown Bat ().

Individual marking techniques are critical for studying animals, especially in the wild. Current marking methods for bats (Order Chiroptera) have practical limitations and some can cause morbidity. We tested the p-Chip (p-Chip Corp.

Acute restraint stress rapidly impacts reproductive neuroendocrinology and downstream gonad function in big brown bats (Eptesicus fuscus).

Animals face unpredictable challenges that require rapid, facultative physiological reactions to support survival but may compromise reproduction. Bats have a long-standing reputation for being highly sensitive to stressors, with sensitivity and resilience varying both within and among species, yet little is known about how stress affects the signaling that regulates reproductive physiology. Here, we provide the first description of the molecular response of the hypothalamic-pituitary-gonadal (HPG) axis of male big brown bats (Eptesicus fuscus) in response to short-term stress using a standardized restraint manipulation.

Ontogeny of cranial musculoskeletal anatomy and its relationship to allometric increase in bite force in an insectivorous bat (Eptesicus fuscus).

Bite force is a performance metric commonly used to link cranial morphology with dietary ecology, as the strength of forces produced by the feeding apparatus largely constrains the foods an individual can consume. At a macroevolutionary scale, there is evidence that evolutionary changes in the anatomical elements involved in producing bite force have contributed to dietary diversification in mammals. Much less is known about how these elements change over postnatal ontogeny.

Non-destructive methods to assess pesticide exposure in free-living bats.

Bat populations are dwindling worldwide due to anthropogenic activities like agriculture, however the role that pesticide exposure plays on these declines is unclear. To address these research gaps, we first need to develop reliable methods to detect and monitor exposure to environmental pollutants and its effects on free-living bats. The use of biomarkers is a sensitive and informative tool to study sublethal effects in wildlife, however it requires laboratory validation and integrative approaches to be applicable to free-living species.

Big brown bats experience slower epigenetic ageing during hibernation.

Comparative analyses of bats indicate that hibernation is associated with increased longevity among species. However, it is not yet known if hibernation affects biological ageing of individuals. Here, we use DNA methylation (DNAm) as an epigenetic biomarker of ageing to determine the effect of hibernation on the big brown bat, .

A comparison of thermal sensitivities of wing muscle contractile properties from a temperate and tropical bat species.

Endotherms experience temperature variation among body regions, or regional heterothermy, despite maintaining high core body temperatures. Bat forelimbs are elongated to function as wings, which makes them vulnerable to heat loss and exaggerates regional heterothermy. A tropical bat species, Carollia perspicillata, flies with distal wing muscles that are substantially (>10°C) cooler than proximal wing muscles and significantly less temperature sensitive.

Erratum to: Skin pH varies among bat species seasons and between wild and captive bats.

[This corrects the article DOI: 10.1093/conphys/coab088.].

Immunoreactive distribution of gonadotropin-inhibitory hormone precursor, RFRP, in a temperate bat species (Eptesicus fuscus).

Gonadotropin-inhibitory hormone (GnIH, also known RFRP-3 in mammals) is an important regulator of the hypothalamic-pituitary-gonadal axis and downstream reproductive physiology. Substantial species differences exist in the localization of cell bodies producing RFRP-3 and patterns of fiber immunoreactivity in the brain, raising the question of functional differences. Many temperate bat species exhibit unusual annual reproductive patterns.

Skin pH varies among bat species and seasons and between wild and captive bats.

Skin is a key aspect of the immune system in the defence against pathogens. Skin pH regulates the activity of enzymes produced both by hosts and by microbes on host skin, thus implicating pH in disease susceptibility. Skin pH varies inter- and intra-specifically and is influenced by a variety of intrinsic and extrinsic variables.

Quantification of Urinary Sex Steroids in the Big Brown Bat ().

AbstractBats (order Chiroptera) are the second largest group of mammals, diverging ~52.5 million years ago. Many species exhibit an unusual reproductive cycle and extreme longevity without reproductive senescence, yet steroid profiles exist for few bats.

DNA methylation predicts age and provides insight into exceptional longevity of bats.

Exceptionally long-lived species, including many bats, rarely show overt signs of aging, making it difficult to determine why species differ in lifespan. Here, we use DNA methylation (DNAm) profiles from 712 known-age bats, representing 26 species, to identify epigenetic changes associated with age and longevity. We demonstrate that DNAm accurately predicts chronological age.

High frequency sensitivity to interaural onset time differences in the bat inferior colliculus.

Many neurons in the auditory midbrain are tuned to binaural cues. Two prominent binaural cues are the interaural level difference (ILD) and the interaural time difference (ITD). The ITD cue can further be subdivided into the ongoing envelope ITD cues and transient onset ITD cues.

Development of hearing in the big brown bat.

We studied the development of hearing in newborn pups of the big brown bat, Eptesicus fuscus. In the majority of pups, the opening of both outer auditory canals occurred on or before postnatal day (PND) 7, but in some, it extended to PND 11. Using repeated auditory brainstem response (ABR) recordings, we tracked the progressive development and maturation of auditory sensitivity in 22 E.

Seasonal transfer and quantification of urinary estradiol in the big brown bat (Eptesicus fuscus).

Growing evidence shows that sex steroids not only act within the individual whose glands produce them; they can also act on proximate conspecifics. Previous studies show that exogenous 17β-estradiol (E) can be absorbed both nasally and percutaneously, arriving in blood, neural, reproductive, and peripheral tissues. When male bats were injected with radiolabeled E (H-E) and housed with females during the mating season, radioactivity was reliably measured in the females' tissues.

Sonar strobe groups and buzzes are produced before powered flight is achieved in the juvenile big brown bat, .

Laryngeally echolocating bats produce a rapid succession of echolocation calls just before landing. These landing buzzes exhibit an increase in call rate and a decrease in call peak frequency and duration relative to pre-buzz calls, and resemble the terminal buzz phase calls of an aerial hawking bat's echolocation attack sequence. Sonar strobe groups (SSGs) are clustered sequences of non-buzz calls whose pulse intervals (PIs) are fairly regular and shorter than the PIs both before and after the cluster, but longer than the PIs of buzz calls.

Effect of sound pressure level on contralateral inhibition underlying duration-tuned neurons in the mammalian inferior colliculus.

Duration tuning in the mammalian inferior colliculus (IC) is created by the interaction of excitatory and inhibitory synaptic inputs. We used extracellular recordings and paired tone stimulation to measure the strength and time course of the contralateral inhibition underlying duration-tuned neurons (DTNs) in the IC of the awake bat. The onset time of a short, best duration (BD), excitatory probe tone set to +10 dB (re threshold) was varied relative to the onset of a longer-duration, nonexcitatory (NE) suppressor tone whose sound pressure level (SPL) was varied.

Tuning for rate and duration of frequency-modulated sweeps in the mammalian inferior colliculus.

Responses of auditory duration-tuned neurons (DTNs) are selective for stimulus duration. We used single-unit extracellular recording to investigate how the inferior colliculus (IC) encodes frequency-modulated (FM) sweeps in the big brown bat. It was unclear whether the responses of so-called "FM DTNs" encode signal duration, like classic pure-tone DTNs, or the FM sweep rate.

Progesterone transfer among cohabitating female big brown bats (Eptesicus fuscus).

Experiments using female mice and bats have demonstrated that tritium-labeled 17β-estradiol (H-E) can be absorbed via cutaneous and intranasal routes and distributed to reproductive and neural tissues. Radioactivity has also been measured in tissues of untreated females after 48h cohabitation with H-E injected males. The present study was designed to quantify steroid transfer among female bats.

Frequency tuning of synaptic inhibition underlying duration-tuned neurons in the mammalian inferior colliculus.

Inhibition plays an important role in creating the temporal response properties of duration-tuned neurons (DTNs) in the mammalian inferior colliculus (IC). Neurophysiological and computational studies indicate that duration selectivity in the IC is created through the convergence of excitatory and inhibitory synaptic inputs offset in time. We used paired-tone stimulation and extracellular recording to measure the frequency tuning of the inhibition acting on DTNs in the IC of the big brown bat ().

Sensory-based niche partitioning in a multiple predator - multiple prey community.

Many predators and parasites eavesdrop on the communication signals of their prey. Eavesdropping is typically studied as dyadic predator-prey species interactions; yet in nature, most predators target multiple prey species and most prey must evade multiple predator species. The impact of predator communities on prey signal evolution is not well understood.

Seasonal and reproductive effects on wound healing in the flight membranes of captive big brown bats.

The flight membranes of bats serve a number of physiological functions important for survival. Although flight membrane injuries are commonly observed in wild-caught bats, in most cases the damage heals completely. Previous studies examining wound healing in the flight membranes of bats have not taken into consideration energy constraints that could influence healing times.

Morphological, olfactory, and vocal development in big brown bats.

Using a within subjects design, we documented morphological, bioacoustical and behavioral developmental changes in big brown bats. Eptesicus fuscus pups are born naked and blind but assume an adult-like appearance by post-natal day (PND) 45 and flight by PND 30. Adult females use spatial memory, acoustic and olfactory cues to reunite with offspring, but it is unclear if pups can recognize maternal scents.