Banca de DEFESA: JÚLIA FANNY DE JESUS RESENDE

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JÚLIA FANNY DE JESUS RESENDE
DATE: 26/08/2022
TIME: 09:00
LOCAL: Google meete
TITLE:

Gracilaria caudata AS A POTENTIAL INGREDIENTE IN Oreochronis niloticus FEED: EFFECT ON ZOOTECHNICAL PERFORMANCE, BODY COMPOSITION, LIVER HISTOLOGY AND ORGANOLEPTIC CHARACTERISTICS

KEY WORDS:

Animal nutrition; Seaweeds; Chemical composition; Sensory analysis; Liver histology.

PAGES: 62
BIG AREA: Outra
AREA: Ciências Ambientais
SUMMARY:

Nile tilapia (Oreochromis niloticus) has been attracting attention in the scenario of freshwater fish production, being one of the three most cultivated species for food purposes. It is valued for its high degree of adaptability and resistance, fast growth and meat with desirable qualities such as low fat and firm texture consumers. To maximize animal production, dietary supplements are sought to protect animal health, to improve zootechnical performance and to produce good-quality meat. In this sense, this research aimed to evaluate the effect of the seaweed Gracilaria caudata as an ingredient in the diet of the fish Oreochromis niloticus (Nile tilapia), focusing on growth performance, survival, body composition, liver structure and organoleptic characteristics. To achieve that, this dissertation was structured in two chapters. The first chapter evaluates the potential of the seaweed G. caudata on the performance of Nile tilapia while the second one addresses the organoleptic characteristics of fish fed with different concentrations of the seaweed. In the first chapter, a 30-day feeding experiment was carried out, in which 96 juveniles of O. niloticus were randomly assigned to 12 experimental units at a stocking density of eight individuals per unit. Four treatments were tested: commercial feed used as control (D0) and three diets supplemented with G. caudata with including of 10% (D1), 20% (D2) and 30% (D3). The addition of 10% and 20% of seaweed did not affect the zootechnical performance of the cultivated animals. Changes in fish body composition seem to be related to seaweed consumption, with increased moisture, protein and ash and reduced lipid content as a function of the level of inclusion. Histological analyses of the liver also showed the same trend, with fat reduction with increasing seaweed addition. In the second chapter (sensory quality), a 35-day experiment was carried out with adult animals, with the same seaweed inclusion rates. The organoleptic properties (flavor, odor, texture and general impression) of Nile tilapia meat were not affected by the diets tested. Although no significant differences were observed, the tilapia fillets from treatments D0 and D1 were considered "very good" in terms of flavor. This analysis may help the aquaculture industry to evaluate new ingredients or diets for fish feed, impacting fillet quality. In conclusion, G. caudata may be incorporated in the Nile tilapia feed between 10% and 20%, without any negative effect on the zootechnical performance or liver abnormality of the fish.

COMMITTEE MEMBERS:
Presidente - 1279472 - ELIANE MARINHO SORIANO
Externo ao Programa - 2178762 - MARCOS ROGERIO CAMARA - nullExterno à Instituição - VINICIUS PERUZZI DE OLIVEIRA - UFRJ