Auditory Contact Research Articles

A novel antibody that neutralizes corticotropin-releasing factor attenuates the cardiovascular effects of chronic social defeat stress in mice

According to the World Health Organization, cardiovascular disease (CVD) continues to be the leading cause of death worldwide. While a myriad of genetic and environmental factors influence the development of CVD, there are several lines of evidence suggesting that psychological stress contributes to health disparities in CVD observed amongst different populations. Our lab seeks to understand the effects of psychosocial stress on cardiovascular health using a model of chronic social defeat stress (CSDS) in mice. In this paradigm, male C57BL/6 mice undergo brief daily defeat sessions and are housed in the same cage as the larger, more aggressive CD1 defeater mouse, separated by a polycarbonate divider that allows for continuous visual, auditory, and olfactory contact while preventing physical contact. We have previously demonstrated that this paradigm causes robust and persistent elevations in blood pressure, indices of chronic inflammation, elevations in plasma corticosterone and cardiac and adrenal hypertrophy. Social defeat also leads to robust activation of corticotropin releasing factor (CRF) neurons within the paraventricular nucleus of the hypothalamus (PVN). In the present studies, we investigate whether we can alleviate some of the adverse effects of CSDS through targeting the HPA axis using CTRND05, a novel anti-CRF antibody. Adult male C57BL/6 mice were assigned to either CSDS or control (paired) housing. Following 14 days of CSDS or control housing, mice were treated with one injection of CTRND05 (25 mg/kg, i.p.) or vehicle (IgG), followed by 14 more days of CSDS or control housing. A booster administration of CTRND05 (12.5 mg/kg, i.p.) was given 7 days after the initial dose. Adrenal weights were significantly reduced in pair housed mice treated with CTRND05 compared to pair housed mice treated with IgG, and there was a trend towards a reduction in adrenal weight of CSDS mice treated with CTRND05 in comparison with CSDS mice treated with IgG. There was also a trend for reduced basal corticosterone in CSDS mice treated with CTRND05. Importantly, while IgG treatment had no effect on the systolic blood pressure (SBP) of CSDS mice, treatment with CTRND05 significantly lowered the SBP of CSDS mice when compared with pre-treatment. These data suggest that targeting CRF may serve as a therapeutic tactic for treatment of stress-related hypertension. R35HL150750, R01HL136595. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

DETERMINING AUTONOMOUS SENSORY MERIDIAN RESPONSE (ASMR) EFFECT ON ADVERTISING EFFECTIVENESS BY USING CONTENT ANALYSIS

Autonomous Sensory Meridian Response which is abbreviated as ASMR, is emerging as a content that brands prefer to use in their ads recently. However, the effects of ASMR contents on consumers can be positive as well as negative, making ASMR contents a risky choice for brands. In the literature, the outputs on the advertising effectiveness of ASMR contents are quite insufficient. Based on this gap, it is aimed to reveal the effect of ASMR on advertising effectiveness by obtaining consumer insights into ASMR contents in ads. For this purpose, ASMR-containing Permolit Paint and LC Waikiki (LCW) ads published in Turkey were determined and the comments for these ads in the digital media platforms were analyzed by content analysis. The results showed that both ASMR ads were mostly evaluated as relaxing and positive, but also provided a positive behavioral attitude such as using the brand and voluntarily watching the ads repeatedly. Yet, some auditory triggers, especially whispering and contact with the product surface, were found to be a prominent source of negative attitude towards LCW's advertisement.

Behavior of lambs and ewes of the Polish Merino and Wrzosówka breeds simulating different conditions of loss during extensive grazing

Extensive sheep grazing carries both benefits and risks. Whereas the benefits include reduced labor input and optimal (close to natural) welfare conditions for sheep, the risks involve a danger of lambs getting lost on the pasture. The objective of this study was to compare the behavior of lambs and their mothers belonging to two breeds (Polish Merino and Wrzosówka) in three experiment systems simulating the conditions in which lambs tend to get lost on the pasture during extensive grazing: 1) with visual and auditory contact, 2) with auditory contact, and 3) without visual-auditory contact with the flock. Two main questions were analyzed about the first three months of the lambs’ life: 1) the time of finding the flock by the lambs and 2) the behavior patterns of the lambs and ewes, such as the lambs’ movements, the lambs’ and mothers’ vocalization, the reaction to the curtain, the reaction to the observer, and the lambs’ behavior in the field. The study found that the flock finding time in the first and third month of the lambs’ life (experiments 1 and 2, respectively) was shorter in the Wrzosówka breed than in the Merino breed (p ≤ 0.05). Regardless of the scenario, the most frequently observed reactions in the lamb flock were flock calling and navigating to the flock by the shortest route. In the absence of visual and auditory contact, the most frequent response of the Polish Merino and Wrzosówka lambs was to run to the top of the hill and search for the flock. In the third month of life, the lambs of both breeds began to show a higher degree of independence, and the observed patterns of their behavior were similar. The results of the study show that in the first two months of life, the Wrzosówka lambs found the flock faster and were better oriented in the field than the Merino lambs. In the third month of life, the differences in the behavior patterns of the two breeds became very small. This finding could indicate that during extensive grazing, lambs of some breeds, especially those subjected to intensive artificial selection such as the Merino breed, may require more care of the breeder in the first two months of their life.

‘connEcted caesarean section’: creating a virtual link between MOthers and their infanTs to ImprOve maternal childbirth experieNce – study protocol for a PILOT trial (e-motion-pilot)

IntroductionOne-third of mothers rate their childbirth as traumatic. The prevalence of childbirth-related post-traumatic stress disorder (CB-PTSD) is 4.7%. Skin-to-skin contact is a protective factor against CB-PTSD. However, during a caesarean...

5 Plasma cortisol responses of horses in equine assisted activities

Documentation of positive physical, social, psychological, and physiological outcomes in humans following interactions with horses has led to an increase of interest in and availability of programs offering equine assisted services (EAS). The effects of EAS programming and clients on horse well-being is unclear and needs further study given the increasing scrutiny the public sector gives to issues of animal welfare in the agricultural and equine industries. The objective of this study was to investigate the stress response of horses in equine assisted activities (EAA) via measurement of plasma cortisol. Horses were assigned to a 30 min adaptive horsemanship lesson with a veteran with posttraumatic stress disorder (PTSD) (EAA, n = 6, 20.3 ± 1.9 yrs, mean ± SE) or a concurrent 30 min standing control with no interaction in a small area of the same arena (CON, n = 6, 13.8 ± 1.7 yrs) such that horses served as conspecifics for one another with visual, olfactory, and auditory contact for the 8-week study. Lessons occurred weekly at the same time for a given pair of horses and veteran (between 1100 and 1500). EAA horses regularly participated in this type of work. CON horses were regularly ridden and handled by recreational riders. Indwelling jugular catheters were placed using sterile technique and local lidocaine anesthetic at least 30 min beforethe start of the lesson. Blood samples were collected into lithium heparin coated tubes at the start of the lesson (0), 3 min in (3), 5 min in (5), 25 min in (25), and 30 min in (30). Samples were immediately placed on ice until centrifuged at 2,500 rpm for 5 min. Plasma was aliquoted and stored at −80°C until assayed for cortisol using a solid phase chemiluminescent immunoassay system (Immulite) validated for use in horses. Data were analyzed using a mixed model ANOVA with fixed effects of treatment (EAA, CON), time point, week, and their interactions and a random effect of horse. Time point and week were considered repeated measures. Statistically different means were separated using Tukey's method. Significance was set at P ≤ 0.05. Cortisol concentrations during EAA ranged from 1.85 ± 0.26 µg/dL at time point 0 in wk 1 to 2.88 ± 0.30 µg/dL at time point 30 in wk 8 with no significant differences. Cortisol in CON horses was elevated at time points 25 (3.14 ± 0.19 µg/dL) and 30 (3.13 ± 0.19 µg/dL) as compared with time points 0 (2.56 ± 0.12 µg/dL), 3 (2.53 ± 0.13 µg/dL), and 5 (2.58 ± 0.14 µg/dL) (P ≤ 0.05). Horses appeared to be more stressed by confinement and limited contact with humans than by interactions with veterans with PTSD.

An exploratory study of negative and positive facial expressions of carriage horses during nocturnal resting

Studies on the welfare of carriage horses have been addressed during working activity; however, their nocturnal resting behavior remains poorly explored. The aim of our study was to quantify the frequency of negative, positive, and neutral facial expressions (FE) of carriage horses used in tourism displayed under nocturnal resting conditions. Observations were carried out in the tropical city of Mérida, México, from January to March 2021. Nine crossbreed horses, including 3 mares and 6 geldings (400 ± 50 kg, 9-20 years old), were used. Prior to FE observations, an evaluation of resting locations was performed with regard to available surface area, movement restriction, floor and roof conditions, and visual and auditory contact between horses. A 40-point veterinary health examination was also performed on all horses. FE were identified based on the Horse Grimace Scale and EquiFacs coding system. Occurrences of stiffly backwards ears EAD103, orbital tightening AU145, tension above the eye area AU5, prominent strained chewing muscles AU18, strained mouth and pronounced chin AU24+17, and strained nostril and flattening of the profile EAD103+AUH13 were considered negative; ears forward EAD101 and nostril dilation AD38 were considered positive; and right ear forward EAD101R and without movement (WM) were considered neutral. All FE were photographed with a hidden camera (GoProHero3+, 12 megapixels) every minute for at least 8 hours overnight immediately following a randomly selected working day. Good resting location scores were fulfilled by 100% of horses except for good floor and roof conditions (66.6%). Physical health evaluations resulted in 90% of horses with good health scores. The most frequent FE per hour were WM (27.0 ± 5.6), EAD101 (12.8 ± 5.6), and EAD103 (8.9 ± 5.8). Statistical differences (P < 0.0001) were found for mean comparison test between neutral (15.7 ± 3.1 FE/h), positive (6.6 ± 2.9 FE/h), and negative (2.4 ± 1.3 FE/h) FE/h. No significant differences were found for the frequency of neutral, positive, or negative FE/h according to age, body condition score, or health status of the animals, nor according to floor and roof condition of resting locations. The higher frequency of neutral and positive FE compared to negative FE is consistent with the good health scores and generally good conditions of resting locations in the large majority of the horses observed.

Administration of a single dose of long-acting injectable progesterone formulation reduces the stress response to weaning in anestrous ewes

High circulating progesterone concentrations decrease the responses to stressful situations in farm ruminants. We hypothesized that administering a single dose of long-acting progesterone formulation reduces the stress response of anestrous ewes to weaning. The aim of this study was to compare the behavioral, cortisol, and blood protein responses to weaning of anestrous ewes treated or not, with a single dose of a long-acting progesterone formulation. A complementary aim was to characterize the bioavailability of progesterone after this treatment. Thirty-six multiparous single-lambing Corriedale ewes and their lambs were used in this study. The lambs were weaned at 6:30 h when they were 65 d old (d0), and were taken to another paddock without chemical, visual or auditory contact with their mothers, while the ewes remained in the same paddock. Immediately before weaning, while 19 ewes received oil based long-acting progesterone formulation, other 17 ewes remained as controls, receiving sunflower oil. Twelve ewes from each group were used for behavioral recordings, the other 5 untreated ewes and 7 treated ewes were used to characterize the cortisol response and the progesterone profile. Behaviors were recorded every 10th min for 3 h in the morning and 3 h in the afternoon on day minus 3, d0 and d2, and expressed as percentage of recordings each animal displayed each behavior on each day. Treated ewes were recorded more times standing up than ewes on the day of weaning (P < 0.05), but the reverse result was found 2 d after (P < 0.01). Treated ewes were recorded more times lying down than control ewes on d2 after weaning (P < 0.0001), when treated ewes were observed fewer times walking than control ewes (P = 0.0004), as also happened the day of weaning (P < 0.0001). On the day of weaning, treated ewes grazed and paced less than control ewes (P = 0.001 and P = 0.009). Treated ewes ruminated more than control ewes on the day of weaning (P = 0.02) and 2 d later (P = 0.0002). Control ewes also secreted more cortisol than progesterone-treated ewes (P = 0.03), with no effect of the treatment on the concentration of total proteins, albumin or globulins. While control ewes never had luteal progesterone concentrations (>0.5 ng/mL), treated ewes achieved luteal progesterone concentrations 2 h after its administration, and remained well above luteal levels until 15 h after administration. The administration of a single dose of long-acting progesterone formulation appears to be a viable choice in reducing the stress to weaning in ewes. Ewes treated with progesterone coped better with weaning, returning to their normal basal behavior earlier than untreated ones, and secreting lower cortisol levels.

Sexual performance and semen quality of pubertal lambs treated with different weaning methods.

The objective of this study was to determine the effect of the weaning method on lamb stress, body weight, sexual behavior, and semen quality of Saint Croix male lambs. The present study was carried out during the late spring and summer of 2018 in the northeast of Mexico. Sixty male lambs born as twins or triplets (3.2 0.6 kg birth weight) and weaned at 60 d of age (19.21 1.8 kg weaning weight) were divided into two weaning methods: complete separation from the dams (CS; the lambs were moved to a pen that was at 500 m of distance from the dams) and separation with contact from the dams (SCD); the lambs were physically separated by a steel mesh that prevented the lambs from having the possibility of sucking milk from their mothers, but they maintained permanent visual and auditory contact. Cortisol levels were determined 3 d before and 7 d after weaning. Lambs were evaluated as 3-month-old lambs for sexual behavior and semen quality for 9 weeks. The effects of the weaning method (M), week (W), and the interaction M W were significant on body weight and cortisol levels (). The SCD lambs had higher cortisol levels at 3, 5, and 7 d after weaning than CS lambs (). The CS lambs had higher body weight during the first 4 weeks after weaning than SCD lambs (). The weaning method had no effect on scrotal circumference, sexual behavior, and semen quality traits, except for progressive sperm motility, being better for the lambs that were completely separated (). The results from this study show that complete separation of lambs and ewes at weaning is an effective method to reduce lamb stress and improve lamb growth after weaning, but it did not have long-term effects on sexual behavior and semen quality of Saint Croix male lambs.

Effect of contact with male on the physical and chemical qualities of eggs of black harco layers

A group of 30 Black HARCO laying hers were reared together with 3 mature cocks, while another group were reared in an adjacent pen without cocks. Thus, while the first group of hens had full physical contact (including mating) with the males, the second group was restricted only to auditory and visual contacts with the males. Twelve eggs were selected at 2 - weekly interval within a 12 - week period from each group and chemically analyzed for total protein, cholesterol in the yolk were determined by colourimetric methods while the shell calcium concentration was determined by a litrumetric method. Egg yolk cholesterol was higher (P&lt;0.05) in hens exposed to full physical contact with the males (16.78 vs 14.20 mg/ml) whereas egg yolk protein, albumen protein and egg shell calcium concentrations were not significantly different (P&gt;0.05) between the 2 groups. Egg weight, egg components weights and hen day egg production were also lower in those hens exposed to full contact with the males. Physical contacts (including mating) between the cock and hen resulted in higher yolk cholesterol and lower physical qualities of eggs produced under such management system.

Auditory and spatial regimes of United States colonial rule in Baguio, Philippines

ABSTRACT Control over geographic and sonic space was integral to the United States’ imperial project in the Philippines. This article explores how the creation of the hill station of Baguio was achieved both spatially and sonically through the work of US urban designers such as Daniel H. Burnham. In the early twentieth century, Burnham’s plans for Baguio (and Manila) inspired a model of auditory and spatial planning that colonial administrators hoped to replicate across the archipelago. In this context, I explore how the design and control of Baguio’s auditory environment was part of a wider process to transforming the rural military outpost into a comfortable resort city for U.S. expatriates, members of the Filipino elite, and others to escape the noise, heat, disease and insurgency of Manila and the lowland areas. Furthermore, the article explores Baguio as an “auditory contact zone” where sound configured and framed the interactive dimensions of the imperial encounter between Filipinos and US expatriates. As I argue, the reengineering of urban spaces, such as Baguio, under the US colonial administration was integral in establishing sound as a material symbol of imperial power.

Maternal presence influences vocal development in the Japanese quail (Coturnix c. japonica)

AbstractSocial influences on vocal development of young birds have been widely studied in oscine songbirds who learn to sing by vocal imitation of conspecifics, mainly male adults. In contrast, vocal development of non‐vocal learners such as Galliformes is considered as being under strong genetic influence and independent of the social environment. In this study, we investigated the role of the mother on the vocal development of young Japanese quail (Coturnix coturnix japonica). We compared the vocal development of mothered and non‐mothered chicks during the first 21 days of life. We analysed the structural changes of two vocalisations: a) the rally call, emitted during long‐distance communication and in stressful situations, b) the contact call, emitted during short‐distance communication when chicks are in visual and/or auditory contact with congeners. We showed that temporal and spectral structures of the two types of calls changed during development and differed between mothered and non‐mothered chicks. These results demonstrate that maternal presence influences the vocal development of the young in the Japanese quail. Even if the adaptive value of such changes was not assessed, these results highlight that plasticity of vocalisations in species considered as non‐vocal learners has been underestimated.

Effects of auditory feedback on movements with two-segment sequence and eye-hand coordination: Using a short auditory contact cue

During sequential reaches to multiple targets, eye and hand movements are highly coordinated, and the gaze is anchored to each target until the reaching hand makes contact to each of them. Such contact events are monitored by multimodal (visual, proprioceptive) sensory systems, and one function of the gaze anchoring to each target is verification of successful target contact (reach completion). The present study focused on this verification function and examined how planning and control of eye and hand movements during two-segment eye-hand movements are affected by augmented auditory feedback of reach completion. Young adults made a reach to the first target with a saccade, and then made another saccade to the second target in blocked trials. An auditory target-contact cue condition delivered four short sounds during the initial reach, and the last sound was synchronized with target contact, whereas a control condition lacked the last target-contact sound. The results showed that saccadic reaction time increased with the target-contact cue, especially when the reaching accuracy demand was high. The reach also became slower with lower peak velocity and longer time to peak velocity with that cue, suggesting that the limb-motor system lower the preplanned speed of the reach in a top-down fashion for a better preparation toward reach completion. However, no auditory effects were found for the timing of gaze shift to the second target. These results were different from those seen in previous studies, indicating that the effects of the additional auditory contact feedback differ depending on behavioral tasks and cue characteristics.

Transmission Disrupted: Modeling Auditory Synaptopathy in Zebrafish.

Sensorineural hearing loss is the most common form of hearing loss in humans, and results from either dysfunction in hair cells, the sensory receptors of sound, or the neurons that innervate hair cells. A specific type of sensorineural hearing loss, referred to as auditory synaptopathy, occurs when hair cells are able to detect sound but fail to transmit sound stimuli at the hair-cell synapse. Auditory synaptopathy can originate from genetic alterations that specifically disrupt hair-cell synapse function. Additionally, environmental factors such as noise exposure can leave hair cells intact but result in loss of hair-cell synapses, and represent an acquired form of auditory synaptopathy. The zebrafish model has emerged as a valuable system for studies of hair-cell function, and specifically hair-cell synaptopathy. In this review, we describe the experimental tools that have been developed to study hair-cell synapses in zebrafish. We discuss how zebrafish genetics has helped identify and define the roles of hair-cell synaptic proteins crucial for hearing in humans, and highlight how studies in zebrafish have contributed to our understanding of hair-cell synapse formation and function. In addition, we also discuss work that has used noise exposure or pharmacological mimic of noise-induced excitotoxicity in zebrafish to define cellular mechanisms underlying noise-induced hair-cell damage and synapse loss. Lastly, we highlight how future studies in zebrafish could enhance our understanding of the pathological processes underlying synapse loss in both genetic and acquired auditory synaptopathy. This knowledge is critical in order to develop therapies that protect or repair auditory synaptic contacts.

Calf presence and estrous response, ovarian follicular activity and the pattern of luteinizing hormone in postpartum Bos indicus cows.

The main objective of the present experiment was to assess the effect of temporary weaning on the onset of estrus, ovarian follicular activity and secretion of luteinizing hormone in Bos indicus cows. Forty six mature cows were divided into three groups 1) calves were weaned for 72 h allowing auditory, olfactory and visual contact with their dams (VISUAL, n = 17), 2) calves without contact with their dams for 72 h (NC, n = 17) and 3) calves not weaned and in constant contact with their dams (CTRL, n = 12). Estrus was synchronized in all cows using CIDR for 9 days plus 2 mg of estradiol benzoate given at CIDR insertion. The VISUAL group had a greater (P < 0.05) proportion of cows in estrus (76.5%) compared to the CTRL group (16.7%), but no differences were found when compared to the NC group (58.8%). The VISUAL group had a greater proportion of animal that ovulated (76.5%) compared to CTRL (33.3%) and NC groups (64.7%; P = 0.059). Duration of estrus was shorter (P = 0.04) in the VISUAL (8.4 ± 4.4 hours) than in the NC (12.9 ± 13.4 hours) however, CTRL treatment (11 ± 1.4 hours) was not different from either of these two groups. LH concentration after implant removal was similar among treatments and started to increase at 36 h post CIDR removal. Only in the CTRL group was there an obvious increase by 54 h after implant removal. Follicular size increased in diameter from 36 h and were evident in treatments and control groups by 60 h (P < 0.05). The VISUAL treatment increased the number of cows ovulating and shortened the length of estrus. VISUAL and NC groups showed a similar response in follicular growth and pattern of circulating LH because of treatment.

Dominance by extremely high aggressive behaviors in relation to genetic microstructure in matrilines

Dominance is an important element of life history. It assures access to resources, which, in turn, affects fitness. By establishing a hierarchy, females may monopolize resources while remaining philopatric. Our genetic study of the sandy pocket mouse, Chaetodipus siccus, has shown a genetic microstructure with private haplotypes in the extremely small species range (∼270km2). To explore these results we evaluate patterns of aggressive–submissive behavior among female C. siccus based on direct dominance, dominance over encounters and dominance based on the defense of food resources. Our findings suggest the presence of aggressive behaviors resulting in the establishment of dominant-subordinate relationship; this relationship remains constant even after a process of visual, auditory and olfactory contact and during the defense of food resources. These results may be linked to a strong territorial behavior that permits the formation of matrilineal nuclei that could be related to a genetic microstructure.

Hand-rearing the critically endangered blue-eyed black lemur (Eulemur flavifrons): milk formula, feeding and socialisation protocols

The blue-eyed black lemur ( Eulemur flavifrons ) is critically endangered in the wild and managed by ex-situ programmes in zoos. The breeding success in the European population is low and within the last five years, there have only been three births that survived. To try to increase the rate of infant survival, a systematic hand-rearing protocol was developed in 2013 and used on five infants from two different females that did not properly raise their infants. Milk formula was created with a mix of human newborn formula and kitten replacement milk. The lemur infants were fed ten times a day at the beginning, on a 24-hour round-the-clock basis. Solid food was offered as early as Day 7 and complete weaning was achieved without any medical issues around Day 107. The socialisation protocol consisted of maintaining permanent visual, olfactory and auditory contact with the parents from the day of the birth. First attempts to put the infants on their mother began as early as Day 2, but results varied, including successes with the parents, with conspecifics or lemurs from another Eulemur species. More work is needed to develop a feeding protocol which would also include the physiological variations in milk composition during the lactation period. Although many studies and reports have described hand rearing mammals, and more specifically lemurs, none of them describe a successful and complete protocol for five infants of the critically endangered blue-eyed black lemur.

Continuous contact with females in estrus throughout the year enhances testicular activity and improves seminal traits of male goats

The “female effect” consists in the stimulation of males' reproductive activity by different signals emitted by females. This stimulation leads to endocrine and behavioral changes that may modify the seasonal pattern of male ruminants. The aims of this experiment were (1) to describe the local reproductive seasonal pattern of Gabon bucks and (2) to determine if continuous chemical, auditory, and visual contact with does in estrus enhances bucks' testicular activity and improves seminal traits throughout the year and modify their seasonal pattern. We used 16 adult Gabon bucks assigned to two experimental groups: nine bucks remained continuously isolated from females (isolated bucks, group IB) and seven bucks were in continuous chemical, auditory, and visual contact through a fence line with does in estrus (stimulated bucks, group SB). During 13 months, scrotal circumference and testosterone concentration were measured weekly and testicular echogenicity was measured every 2 weeks. Also, sperm motility mass and percentage of abnormal spermatozoa were determined, and sperm concentration and total number of motile spermatozoa were calculated every 2 weeks. Testicular echogenicity was greater in IB than that in SB bucks (P < 0.0001), but there were no differences in scrotal circumference. Overall, testosterone concentration was greater in IB than that in SB bucks (P = 0.04), but from late winter to mid-summer, when testosterone concentration presented basal concentrations, SB bucks had greater values than IB bucks (P = 0.004). Sperm concentration (P = 0.05) and sperm mass motility (P = 0.01) were greater in SB than that in IB bucks, and the total number of progressive motile spermatozoa tended to be greater in SB than in that IB bucks (P = 0.1). The percentage of abnormal spermatozoa was lower in SB than in IB bucks in several time points (P < 0.0001). Testicular and seminal traits were better from the end of the spring until mid-autumn. We concluded that does in estrus stimulated bucks' testicular activity, including better seminal quality and a greater increase of testicular fluid content than bucks isolated from females. However, the general seasonal pattern was not modified by stimulation with does in estrus.

Stress-induced decrease of uterine blood flow in sheep is mediated by alpha 1-adrenergic receptors

Prenatal maternal stress can be transferred to the fetus via a catecholamine-dependent decrease of uterine blood flow (UBF). However, it is unclear which group of adrenergic receptors mediates this mechanism of maternal–fetal stress transfer. We hypothesized that in sheep, alpha 1-adrenergic receptors may play a key role in catecholamine mediated UBF decrease, as these receptors are mainly involved in peripheral vasoconstriction and are present in significant number in the uterine vasculature. After chronic instrumentation at 125 ± 1 days of gestation (dGA; term 150 dGA), nine pregnant sheep were exposed at 130 ± 1 dGA to acute isolation stress for one hour without visual, tactile, or auditory contact with their flockmates. UBF, blood pressure (BP), heart rate (HR), stress hormones, and blood gases were determined before and during this isolation challenge. Twenty-four hours later, experiments were repeated during alpha 1-adrenergic receptor blockage induced by a continuous intravenous infusion of urapidil. In both experiments, ewes reacted to isolation with an increase in serum norepinephrine, cortisol, BP, and HR as typical signs of activation of sympatho-adrenal and the hypothalamic-pituitary-adrenal axis. Stress-induced UBF decrease was prevented by alpha 1-adrenergic receptor blockage. We conclude that UBF decrease induced by maternal stress in sheep is mediated by alpha 1-adrenergic receptors. Future studies investigating prevention strategies of impact of prenatal maternal stress on fetal health should consider selective blockage of alpha 1-receptors to interrupt maternal–fetal stress transfer mediated by utero-placental malperfusion.

Editorial: Auditory Efferent System: New Insights from Cortex to Cochlea.

Editorial: Auditory Efferent System: New Insights from Cortex to Cochlea.

Resposta endócrina à contenção física e isolamento em papagaios-verdadeiros

Resumo: O objetivo deste trabalho foi analisar a resposta dos papagaios-verdadeiros aos procedimentos de contenção e separação física por método não invasivo, como a dosagem das concentrações de metabólitos de glicocorticoides nas excretas. Para tanto, foram utilizadas 24 aves, 17 machos e sete fêmeas, inicialmente mantidas em viveiros amplos e adjacentes, separadas por sexo. Após captura e contenção de três minutos, 13 aves voltaram para os viveiros coletivos e 11 foram alojadas em gaiolas individuais no mesmo recinto dos viveiros, de modo a permitir que as aves isoladas mantivessem contato visual e auditivo com as demais. Para avaliar se os animais responderiam de maneira diferente quando fisicamente isolados ou em grupo, amostras de excretas foram coletadas sequencialmente em intervalos de três horas durante 24 horas para avaliação dos metabólitos de glicocorticoides por enzimaimunoensaio. Não houve efeito significativo de sexo (P=0,5850), tratamento (P=0,6805) e tempo (P=0,2293), e as concentrações de metabólitos de glicocorticoides mantiveram-se dentro da variação diurna esperada para esta espécie. Portanto, ambos os grupos responderam endocrinologicamente de forma semelhante e o estresse de captura e separação física não foi significativo para as aves.