Banca de QUALIFICAÇÃO: JEANE RODRIGUES RODRIGUES

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : JEANE RODRIGUES RODRIGUES
DATE: 31/08/2021
TIME: 15:00
LOCAL: Laboratorio de Neurociencia e Comportamento (LaNeC) unifesspa
TITLE:

The effects of the alarm substance in the tetra oogenesis of Astyanax bimaculatus (LINNAEUS, 1758

KEY WORDS:

Club cells

Stress

Gonadal morphology

Fish reproduction

PAGES: 16
BIG AREA: Ciências Biológicas
AREA: Fisiologia
SUBÁREA: Fisiologia Geral
SUMMARY:

The fish group is one of the largest and most diverse among vertebrates, with about 32,000 identified species, also representing about 50% of living beings. Due to the diversity of species, fish have the widest range of reproductive strategies, allowing the group to inhabit the most diverse environments from waters with a temperature below 0 °C to waters of 40 °C, which have great variation in their physicochemical parameters . In addition, they also face challenges in the search for food and spawning sites, conflicts with conspecifics by territorial domain or reproductive partners and the pressure of predation, often causing injuries to these animals. These wounds can reach cells present in the skin, called club cells, found in species of the superorder Ostariophysi, such as the lambari Astyanax fasciatus. When injured, these alarm substance (SA) producing cells release this chemical compound into the water, which is perceived by conspecifics and induces a warning sign of danger, altering animal behavior, which may influence reproductive behavior. An obstacle then arises in small and large fish farms, where reproductive management can cause abrasions in the matrices and induce the danger signal, in addition to abrasions between the individuals themselves during reproduction. In this sense, the work intends to evaluate the reproductive behavior, oogenesis and progeny of Astyanax bimaculatus exposed to different concentrations of SA. For this, 60 individuals were collected in the city of São Domingos do Araguaia – PA. Of these, 10 animals were sacrificed for epidermis collection and club cell identification and 20 donor animals were euthanized for the extraction of SA pools. The remaining 30 females were divided into 6 treatments (T1 1ml, T2 3ml, T3 5ml, T4 7ml and T5 9 ml if SA; and T6 control group with 9 ml of distilled water). The animals were acclimated in the exposure aquarium for 3 minutes and individually exposed for 6 minutes, and filmed for further behavioral analysis. The exposed females were euthanized and had their blood and gonads collected 1 hour post-exposure for analysis of plasma cortisol and morphological and stereological analysis, respectively. With the results obtained in the behavioral test, complementary experiments will be carried out to test progeny with 5 exposed females, to analyze the influence of SA on the reproduction and offspring of A. bimaculatus. Histological analysis revealed the presence of club cells in the epithelial tissue of the studied species. However, in the behavioral test it was found that there was no statistical difference in the different concentrations of the alarm substance tested, with a mean speed of 2 ± 1; 2 ± 1; 2 ± 1; 3 ± 3; 2 ± 1 and 2 ± 1 cm/s and freezing at 31 ± 19; 31 ± 21; 46 ± 21; 25 ± 15; 27 ± 19 and 29 ± 26 seconds for T1 (1 ml); T2 (3 ml); T3 (5 ml); T4 (7 ml); T5 (9 ml) and T6 (9 ml control), respectively. In addition to an average absolute swing angle of 18 ± 3; 16 ± 6; 14 ± 3; 15 ± 5; 14 ± 2 and 14 ± 4 degrees for each treatment, respectively. It can only be observed that the animals prefer the bottom area of the aquarium, instead of the surface. With that, new experiments will be carried out to rectify or ratify the obtained results. In addition, oogenesis analysis and progeny testing for the species will also be performed.

BANKING MEMBERS:
Interno - 2368419 - BRUNO MOURA MONTEIRO
Interno - 329.073.508-70 - DIÓGENES HENRIQUE DE SIQUEIRA SILVA - UNESP
Externo à Instituição - CAIO MAXIMINO DE OLIVEIRA - UNIFESSPA