Banca de DEFESA: GIOVANNA ALMEIDA SANTORO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : GIOVANNA ALMEIDA SANTORO
DATE: 23/05/2025
TIME: 13:00
LOCAL: Sala da Pós graduação do PPGBIOEF
TITLE:

Cytoarchitectonic Characterization of the Primary and Secondary Auditory Cortex of Stenella clymene: The Acoustic Chimera of the Atlantic

KEY WORDS:

Keywords (inglês): 1.neuroanatomy 2 conservation 3.cetacean 4.dolphin 5.cytoarchitecture

PAGES: 60
BIG AREA: Ciências Biológicas
AREA: Morfologia
SUMMARY:

Abstract (inglês):

Odontocetes comprise a group of 92 species of toothed cetaceans with diverse habits and limited accessibility for neuroanatomical studies. One species lacking a description of cortical area cytoarchitecture is Stenella clymene, an Atlantic endemic resulting from the hybridization of two other species within this genus. Therefore, this study aims to map and characterize the cytoarchitecture of the primary (A1) and secondary (A2) auditory cortex of Stenella clymene dolphins, as well as to compare them with their phylogenetic ancestors. The samples were obtained from one specimen rescued alive but deceased during rehabilitation. The rescue was conducted by responsible local institutions. Brain sections were prepared from areas corresponding to the primary and secondary auditory regions in other cetacean species, based on reliable literature descriptions. Processing for the study involved Nissl staining (Thionin) for cortical cytoarchitecture analysis, allowing for the characterization of cortical layers and their thicknesses in the different areas. The results consisted of the description of five distinguishable layers, each with unique characteristics and morphofunctional subdivisions, in addition to variations in thickness and behavior across the cortical regions corresponding to the analyzed areas. Distinctions between A1 and A2 areas were observed in parameters such as thickness, cellular arrangement, and orientation, confirming the morphological distinction between primary and secondary areas. Findings were compared with descriptions from other cetacean species, revealing a significant difference in cortical behavior, with a more notable proximity to Stenella coeruleoalba. Furthermore, a brain collection protocol for small cetaceans was developed to contribute to the standardization of scientific knowledge for future analyses of this system. The information generated through this study can assist in future research on auditory function, promoting the advancement of knowledge about the neuroanatomy and neurophysiology of these animals, given that the species lacks cytoarchitectural descriptions in the literature and differentiations between primary and secondary cetacean areas are scarce. Moreover, it contributes to mitigating the impact of human activities in the marine environment and, consequently, to species conservation.

COMMITTEE MEMBERS:
Presidente - 1672446 - SIMONE ALMEIDA GAVILAN
Interno - 4363493 - EXPEDITO SILVA DO NASCIMENTO JUNIOR
Interno - 1076490 - FERNANDO VAGNER LOBO LADD
Externa à Instituição - ANA BERNADETE LIMA FRAGOSO - UERN
Externo à Instituição - JOSÉ RODOLFO LOPES DE PAIVA CAVALCANTI - UERN