Thyroid-mediated otolith growth in tilapia was evaluated by the ontogenic triiodothyronine (T3) profile revealed by radioimmunoassay during the first month after hatching. Thyroid hormone receptor genes (TRalpha and TRbeta) were cloned and only the expression of TRalpha mRNA, quantified by real-time PCR, was similar to the T3 profile. Variations in otolith growth showed median correlation with ...

Otolith shape analysis is one way to identify stocks of different fish species in the marine environment. Length, width, area, perimeter, form factor, aspect ratio, roundness, circularity, ellipticity and rectangularity analyses of otoliths were undertaken to assess patterns of spatial and temporal stock structure of a wide-ranging fish, the Arabian yellow fin sea bream Acanthopagrus arabicus. ...

This study aimed to investigate otolith in Rachycentron canadum in the Persian Gulf and Oman Sea. Sampling lasted from March 2014 to April 2015 in Khouzestan to Sistan and Baloochestan waters. During this period 30 specimens of R. canadum were caught and studied. Trawling time was 2-2½ hours and trawling depth was considered as 10-100 m daily. All the fish were identified and their otolith was ...

This study aimed to investigate otolith in Rachycentron canadum in the Persian Gulf and Oman Sea. Sampling lasted from March 2014 to April 2015 in Khouzestan to Sistan and Baloochestan waters. During this period 30 specimens of R. canadum were caught and studied. Trawling time was 2-2½ hours and trawling depth was considered as 10-100 m daily. All the fish were identified and their otoli...

Despite the importance of symptomatology in the diagnosis of vestibular dysfunction, the qualitative nature of the symptoms related to semicircular canal (canal) versus otolith dysfunction is not fully understood. The purpose of this study was to compare symptoms, and their severity, in individuals with canal versus otolith peripheral vestibular dysfunction. A subjective tool, the Descriptive S...

The chemical composition of fish otoliths may provide information on the environmental exposure histories of fishes if ‘vital effects’ on element incorporation are minimal. In order to use redox-sensitive geochemical proxies, such as manganese, in otoliths to quantify sublethal exposure to hypoxia, the relative influence of endogenous and exogenous controls on otolith composition must first be ...

In October 2010, the vertical distribution, biodiversity and maturity stages of Chaetognatha species were investigated at four stations located off Walvis Bay, Namibia. Seventeen species were detected and classified as pelagic, shallow-mesopelagic, deep-mesopelagic and bathypelagic species based upon the weighted mean depth derived from their average vertical distribution. High abundances of Ch...

The brain integrates sensory input from the otolith organs, the semicircular canals, and the somatosensory and visual systems to determine self-orientation relative to gravity. Only the otoliths directly sense the gravito-inertial force vector and therefore provide the major input for perceiving static head-roll relative to gravity, as measured by the subjective visual vertical (SVV). Intraindi...

Spatiotemporal convergence and two-dimensional (2-D) neural tuning have been proposed as a major neural mechanism in the signal processing of linear acceleration. To examine this hypothesis, we studied the firing properties of primary otolith afferents and central otolith neurons that respond exclusively to horizontal linear accelerations of the head (0.16-10 Hz) in alert rhesus monkeys. Unlike...