Banca de DEFESA: MATHEUS VICTOR VIANA DE MELO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MATHEUS VICTOR VIANA DE MELO
DATE: 21/02/2024
TIME: 10:00
LOCAL: Online via Google Meet
TITLE:

Development of a nanoemulsion for sex reversal of tilapia (Oreochromis niloticus)

KEY WORDS:

Tilapia farming; Monosex; Nanotechnology.

PAGES: 43
BIG AREA: Ciências Biológicas
AREA: Fisiologia
SUMMARY:

Continuous investments are made to drive the development of the animal production market, with a focus on aquaculture. In Brazil, fish exports in 2022 generated a value of 23.8 million dollars, with tilapia representing 98% of this total, contributing to the country being the fourth largest producer of this fish in the world. Tilapia offers production advantages, with a preference for males due to their size and better production control. However, to ensure monosexuality, various technologies are being developed, such as the addition of androgenic hormones to feed, which, if not carefully controlled, can lead to pollution, environmental contamination, and risks for producers. An alternative is the use of controlled release systems, such as nanoemulsions. Therefore, the aim of this study was to produce and characterize a nanoemulsion containing encapsulated 17α-methyltestosterone, associated with tilapia (Oreochromis niloticus) feed for sex reversal induction. Nanoemulsions were produced using mechanical stirring for 24 hours. A full 2³ factorial design was employed to evaluate the influence of soybean oil and surfactants span 80 and tween 80 on the organoleptic and physicochemical characteristics (size, polydispersity index, and zeta potential of vesicles) of the nanoemulsions. The animals were monitored at different growth stages, divided into 4 groups: control, fed only with feed; Commercial Hormone, fed with feed and a commercial veterinary product for masculinization; and groups with 30 mg and 60 mg of testosterone in nanoemulsion added to the feed. Ultimately, their gonads were analyzed to confirm sex. The results indicate that all nanoemulsion samples were homogeneous, opaque, colorless, odorless, and lump-free, except for sample 5, which was slightly thickened. Furthermore, it was possible to observe that the selected nanoemulsion has satisfactory polydispersity index and zeta potential, where those containing higher amounts of span 80 and tween 80 decrease the size of the vesicles and increase the zeta potential. The groups subjected to sex reversal achieved over 90% success in sex reversal, with morphometric measurements larger than the control group and reduced mortality in the groups treated with nanoemulsion. Therefore, it can be concluded that it is possible to use a nanoemulsion system with encapsulated androgenic hormone for efficient sex reversal of tilapia with increased safety and potential for reducing environmental impacts.

COMMITTEE MEMBERS:
Presidente - PABYTON GONCALVES CADENA
Externo ao Programa - 2654735 - DIJACI ARAUJO FERREIRA - UFRPEExterna à Instituição - MARIA DO CARMO DE BARROS PIMENTEL - UFPE