Dataset Information

Re-evaluating the significance of the dive response during voluntary surface apneas in the bottlenose dolphin, Tursiops truncatus.

ABSTRACT: The dive response is well documented for marine mammals, and includes a significant reduction in heart rate (f_H) during submersion as compared while breathing at the surface. In the current study we assessed the influence of the Respiratory Sinus Arrhythmia (RSA) while estimating the resting f_H while breathing. Using transthoracic echocardiography we measured f_H, and stroke volume (SV) during voluntary surface apneas at rest up to 255?s, and during recovery from apnea in 11 adult bottlenose dolphins (Tursiops truncatus, 9 males and 2 females, body mass range: 140-235?kg). The dolphins exhibited a significant post-respiratory tachycardia and increased SV. Therefore, only data after this RSA had stabilized were used for analysis and comparison. The average (±s.d.) f_H, SV, and cardiac output (CO) after spontaneous breaths while resting at the surface were 44?±?6 beats min^-1, 179?±?31?ml, and 7909?±?1814 l min^-1, respectively. During the apnea the f_H, SV, and CO decreased proportionally with the breath-hold duration, and after 255?s they, respectively, had decreased by an average of 18%, 1-21%, and 12-37%. During recovery, the f_H, SV, and CO rapidly increased by as much as 117%, 34%, and 190%, respectively. Next, f_H, SV and CO rapidly decreased to resting values between 90-110?s following the surface apnea. These data highlight the necessity to define how the resting f_H is estimated at the surface, and separating it from the RSA associated with each breath to evaluate the significance of cardiorespiratory matching during diving.

SUBMITTER: Fahlman A

PROVIDER: S-EPMC6565721 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Re-evaluating the significance of the dive response during voluntary surface apneas in the bottlenose dolphin, Tursiops truncatus.

Fahlman A A Miedler S S Rocho-Levine J J Jabois A A Arenarez J J Marti-Bonmati L L García-Párraga D D Cauture F F

Scientific reports 20190613 1

The dive response is well documented for marine mammals, and includes a significant reduction in heart rate (fH) during submersion as compared while breathing at the surface. In the current study we assessed the influence of the Respiratory Sinus Arrhythmia (RSA) while estimating the resting fH while breathing. Using transthoracic echocardiography we measured fH, and stroke volume (SV) during voluntary surface apneas at rest up to 255 s, and during recovery from ...[more]

PMID: 31197193

Similar Datasets

Project description:The mammalian claustrum is involved in processing sensory information from the environment. The claustrum is reciprocally connected to the visual cortex and these projections, at least in carnivores, display a clear retinotopic distribution. The visual cortex of dolphins occupies a position strikingly different from that of land mammals. Whether the reshaping of the functional areas of the cortex of cetaceans involves also modifications of the claustral projections remains hitherto unanswered. The present topographic and immunohistochemical study is based on the brains of eight bottlenose dolphins and a wide array of antisera against: calcium-binding proteins (CBPs) parvalbumin (PV), calretinin (CR), and calbindin (CB); somatostatin (SOM); neuropeptide Y (NPY); and the potential claustral marker Gng2. Our observations confirmed the general topography of the mammalian claustrum also in the bottlenose dolphin, although (a) the reduction of the piriform lobe modifies the ventral relationships of the claustrum with the cortex, and (b) the rotation of the telencephalon along the transverse axis, accompanied by the reduction of the antero-posterior length of the brain, apparently moves the claustrum more rostrally. We observed a strong presence of CR-immunoreactive (-ir) neurons and fibers, a diffuse but weak expression of CB-ir elements and virtually no PV immunostaining. This latter finding agrees with studies that report that PV-ir elements are rare in the visual cortex of the same species. NPY- and somatostatin-containing neurons were evident, while the potential claustral markers Gng2 was not identified in the sections, but no explanation for its absence is currently available. Although no data are available on the projections to and from the claustrum in cetaceans, our results suggest that its neurochemical organization is compatible with the presence of noteworthy cortical inputs and outputs and a persistent role in the general processing of the relative information.

Project description:BACKGROUND:Brucella spp. isolation is increasingly reported in cetaceans, although associated pathologies, including lesions of the musculoskeletal and nervous systems, are less frequently described. Concerning the nervous system, Brucella sp. infection causing meningitis, meningoencephalitis or meningoencephalomyelitis have been extensively reported in striped dolphins (Stenella coeruleoalba), and less frequently in other cetacean species. CASE PRESENTATION:A juvenile female common bottlenose dolphin (Tursiops truncatus) was found stranded alive in Lanzarote (Canary Islands, Spain) in 2005, but died shortly after. On physical examination, the dolphin showed a moderate body condition and was classified as code 2 (fresh dead) at the time of necropsy. The main gross findings were severe multiorgan parasitism, thickened and congested leptomeninges, and (sero)fibrino-suppurative and proliferative arthritis of the shoulder joint. Histopathological examination revealed the distinct features of a sub-acute systemic disease associated with Cetacean Morbillivirus (CeMV) infection. However, brain lesions diverged from those reported in systemic CeMV infection. This led to suspect that there was a coinfecting pathogen, based on the characteristics of the inflammatory response and the lesion distribution pattern in the central nervous system. Brucella sp. was detected in the brain tissue by PCR and Brucella antigen was demonstrated by immunohistochemistry in the brain and shoulder joint lesions. CONCLUSIONS:The zoonotic potential of marine mammal strains of Brucella has been demonstrated both in natural and laboratory conditions. In this study, PCR detected Brucella sp. in the brain of a common bottlenose dolphin stranded in the Canary Islands; the dolphin was also co-infected with CeMV. This is the first detection of Brucella sp. infection in a stranded cetacean in this archipelago. Therefore, we stress the importance of taking adequate measures during the handling of these species to prevent the transmissions of the infection to humans.

Dataset Information

Re-evaluating the significance of the dive response during voluntary surface apneas in the bottlenose dolphin, Tursiops truncatus.

Publications

Re-evaluating the significance of the dive response during voluntary surface apneas in the bottlenose dolphin, Tursiops truncatus.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets