Banca de QUALIFICAÇÃO: EVAGNO JUNIOR DA SILVA FERREIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : EVAGNO JUNIOR DA SILVA FERREIRA
DATE: 26/08/2025
TIME: 10:00
LOCAL: Ambiente virtual
TITLE:

Acute Ammonia Exposure Compromises Reproduction and Embryonic Viability in the Amazonian tetra Astyanax bimaculatus (Linnaeus, 1758)

KEY WORDS:

Astyanax bimaculatus, ammonia toxicity, reproduction, gametogenesis, larval development, aquaculture.

PAGES: 50
BIG AREA: Ciências Biológicas
AREA: Fisiologia
SUBÁREA: Fisiologia Comparada
SUMMARY:

The study evaluated the effects of acute ammonia exposure on the reproduction and embryonic viability of the Amazonian lambari (Astyanax bimaculatus). Adult breeders were exposed to a sublethal ammonia concentration (180 mg/L) for 4 hours before artificial reproduction. Results showed a significant reduction in hatching rates (82.3 ± 0.577 vs. 129 ± 1.73 in controls) and accelerated hatching time (1005 ± 2.58 vs. 1026 ± 3.65 minutes). Gonadal histology revealed impaired gametogenesis, with exposed females exhibiting fewer vitellogenic oocytes and more post-ovulatory complexes, while males showed increased spermatocytes and interstitial tissue but reduced spermatozoa. Larval morphometric analysis indicated delayed growth at 10 days post-hatching, though no morphological abnormalities were observed. These findings highlight the detrimental impact of ammonia on reproductive success and larval development, emphasizing the need for stringent water quality management in aquaculture to mitigate such effects.

COMMITTEE MEMBERS:
Presidente - ***.073.508-** - DIÓGENES HENRIQUE DE SIQUEIRA SILVA - UNESP
Interno - ***.616.542-** - MOYSÉS DOS SANTOS MIRANDA - UFPA
Externo à Instituição - JAYME APARECIDO POVH - UFMS