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Substituição total e parcial da ração comercial por farelo de soja fermentado durante a fase de berçário intensivo do camarão Litopenaeus vannamei

2026-05-26T14:36:20Z

Título: Substituição total e parcial da ração comercial por farelo de soja fermentado durante a fase de berçário intensivo do camarão Litopenaeus vannamei Autor(es): Gomes, Igor Gabriel Rodrigues Ferreira Abstract: The shrimp farming industry has been experiencing a movement towards intensification, which allows an increase in productivity with a better use and of natural resources. The growth of this sector is associated with the availability of quality post-larvae and juveniles. The use of intensive nursery is an important strategy for biphasic systems, providing better results during the grow-out phase, increasing survival and growth of farmed animals. Despite this, its use requires qualified labor and feeds with high levels of crude protein, which represent greater cost and a potential risk to the water quality, thus, to the health of the animals. Thus, it is necessary to develop strategies that allow the improvement of this culture system. This study aimed to evaluate the effect of replacing commercial feed with fermented soybean meal, using a commercial probiotic, composed of a mix of organisms, during the intensive nursery phase of L. vannamei carried out under commercial conditions. Thus, five replacement percentages were evaluated, as 0%, 25%, 50%, 75% and 100%. Zootechnical parameters, water quality, zooplankton density and standard plate count for bacteria of the genus Vibrio spp. in the nursery water were evaluated. It was possible to replace the commercial diet with 100% fermented soybean meal without affecting the final survival, specific growth rate (%) and feed conversion. It was possible to replace the feed up to 50%, without negative effect on average final weight (g) and daily weight gain (g/day). The final average productivity (kg/m³) and yeld (kg/m³) were affected only when the replacement level exceeded 75%. It was possible to replace up to 100% without prejudice to water quality parameters such as pH, dissolved oxygen (mg/L), total ammonia (mg/L), nitrite (mg/L) and alkalinity (mg/L of CaCO3). The total zooplankton density was higher in the SJ25% treatment, when compared to the others, which did not differ (p>0.05). The standard plate count of Vibrio spp. was not influenced by the different replacement levels, the exception being the SJ50% treatment, which reached the highest value (p<0,05). The results indicate that the use of fermented soybean meal can be used as food for L. Vannamei‘s post-larvae in intensive nursery. A maximum replacement rate of 50% is suggested, in order to maintain the pattern of development observed with the use of a protocol with commercial rations. Tipo: Tese

Criopreservação de espermatóforos do camarão marinho Penaeus vannamei em diferentes meios diluidores, adicionado de polissacarídeos sulfatados extraídos de Kelps ascophyllum nodosum, para uso em inseminação assistida

2026-05-19T20:53:35Z

Título: Criopreservação de espermatóforos do camarão marinho Penaeus vannamei em diferentes meios diluidores, adicionado de polissacarídeos sulfatados extraídos de Kelps ascophyllum nodosum, para uso em inseminação assistida Autor(es): Moreira, Francisco Hiago Gadelha Abstract: Sperm cryopreservation constitutes a strategic biotechnology for genetic improvement programs and the conservation of aquatic resources, including shrimp farming. This thesis aimed to evaluate the effect of adding sulfated polysaccharides (SP) extracted from the brown alga Ascophyllum nodosum, as well as the use of powdered coconut water (ACP®) as a diluent, in cryopreservation protocols for spermatophores of the marine shrimp Penaeus vannamei. Two experiments were conducted: in the first, spermatophores were subjected to different freezing media (ACP®, seawater, or 0.2 M sucrose); in the second, the addition or absence of SP to the 0.2 M sucrose solution was evaluated. Spermatophores were frozen using a dry shipper or a freezing ramp, stored in liquid nitrogen for up to 12 months, and subsequently thawed for evaluation of sperm quality. Plasma membrane integrity, sperm morphology, and DNA fragmentation were analyzed, as well as the structural characterization of SP by Fourier-transform infrared spectroscopy. The results demonstrated that the tested protocols were effective in maintaining cellular integrity after thawing, even after long periods of cryogenic storage. The freezing solution and method significantly influenced sperm quality, with emphasis on the dry shipper, which showed better preservation of plasma membrane integrity, including when associated with the use of ACP®. Supplementation of freezing media with SP from A. nodosum positively contributed to the maintenance of post-thaw sperm quality. Assisted insemination using cryopreserved spermatophores resulted in fertilization. It is concluded that the use of algal-derived sulfated polysaccharides and diluents based on powdered coconut water and seawater represents a promising approach for improving cryopreservation protocols for P. vannamei spermatophores, with potential application in assisted reproduction programs and genetic conservation in shrimp farming. Tipo: Tese

Efeito dos óleos essenciais de Citrus latifolia e Citrus sinensis sobre Aeromonas patogênicas isoladas de tilápia-do-Nilo (Oreochromis Niloticus)

2025-10-15T17:31:58Z

Título: Efeito dos óleos essenciais de Citrus latifolia e Citrus sinensis sobre Aeromonas patogênicas isoladas de tilápia-do-Nilo (Oreochromis Niloticus) Autor(es): Amarante, Deborah Oliveira Abstract: Freshwater fish farming in Brazil has seen significant growth in production volume over the last decade. The farming of tilapia (Oreochromis niloticus) stands out due to zootechnical, sensory, and productive factors that have favored its cultivation. However, this activity has been threatened by several bacterial diseases that can affect animals at different stages of life, causing economic losses to fish farmers. Although the use of antibiotics is common to treat bacterial diseases in fish farms, their incorrect use can make microorganisms resistant, causing damage to human health and environmental pollution. An alternative would be the use of herbal medicines, based on essential oils, which can lyse the cell wall, destroying or preventing the growth of pathogenic microorganisms. The objective of this study was to evaluate the potential use of essential oils (EO) from Citrus latifolia (Tahiti lime) and Citrus sinensis (pear orange) as prophylactic or curative measures against bacteria of the genus Aeromonas. In the first phase, water was collected from the Malcozinhado reservoir and fish mucus to prospect for bacteria related to O. niloticus pathogens. The isolates were subjected to biochemical tests, expression of extracellular enzymes related to pathogenicity, susceptibility to antibiotics, and genotypic identification of the strains. The second phase consisted of the extraction of essential oils from Tahiti lime and pear orange, followed by the study of the chromatographic profile and toxicity. The essential oils were subjected to in vitro tests of bactericidal activity through a disc diffusion assay and determination of minimum inhibitory and bactericidal concentrations. The third phase included an in vivo test where tilapia were fed commercial feed supplemented with lime essential oil at concentrations of 800, 1,600, and 3,200 µg/mL for 30 days. After this period, the animals were subjected to a challenge test against A. veronii biovar veronii, followed by hematological and histological analyses. The results revealed the presence of bacteria of the genus Aeromonas, which expressed many factors related to virulence, such as extracellular enzymes and antibiotic resistance profiles. The major compound in orange EO is D-limonene, while in lemon it is γ-terpinene. The analyses indicate greater antimicrobial activity in pear orange EO compared to Tahiti lemon EO. In the in vivo test, there was no statistically significant difference in growth between the treated tilapia groups and the control, but histological images confirm that the animals in the treated groups had a greater number of intestinal villi, indicative of greater capacity for nutrient absorption. Despite the limitations, the results strongly suggest that lemon essential oil is an attractive candidate for improving the treatment of aeromonosis in Nile tilapia and promoting growth in captive fish. Tipo: Tese

Uso de extrato de alho conjugado a revestimento de quitosana na estabilidade em almôndegas elaboradas à base de carne mecanicamente separada de tilápia do Nilo (Oreochromis niloticus)

2025-10-09T17:57:10Z

Título: Uso de extrato de alho conjugado a revestimento de quitosana na estabilidade em almôndegas elaboradas à base de carne mecanicamente separada de tilápia do Nilo (Oreochromis niloticus) Autor(es): Silva, Alynne Rodrigues da Abstract: During the processing and storage of fish products, physical, chemical, and microbiological changes are a major concern due to reduced stability. This study aimed to evaluate the influence of garlic (Allium sativum L.) extract and a commercial chitosan coating on refrigerated meatballs made from mechanically separated meat (MSM) of Nile tilapia (Oreochromis niloticus). The aqueous garlic extract was characterized by in vitro antimicrobial activity analysis using scanning electron microscopy (SEM), high-performance liquid chromatography (HPLC), and Fourier transform infrared spectroscopy (FTIR). The microbiological quality of the MSM was assessed in accordance with current legislation. Five meatball treatments were prepared: three with the addition of garlic extract (1%, 3%, and 6%), in addition to the negative control group without additives and the positive control group with the synthetic additive butylhydroxytoluene (BHT). Each meatball was modeled with 50g of each. The coating was applied exclusively to the 6% garlic extract group. The meatballs were stored in the refrigerator at 4°C for 28 days to assess stability. At time zero, treatment samples were analyzed for water holding capacity (WHC) and cooking loss (CLP), as well as by SEM and determination of the fatty acid profile of the negative control group. Data were analyzed by ANOVA followed by Tukey's test, considering a significance level of p≤0.05. Garlic extract showed significant antimicrobial activity against Staphylococcus aureus and Escherichia coli. FTIR and HPLC characterized the garlic extract, confirming the presence of functional groups containing sulfur and nitrogen compounds, as well as allicin and inulin, associated with antimicrobial and antioxidant activity. A MEV revealed irregular and dispersed microstructures in the extract. The CMS met the microbiological standards of current legislation, demonstrating stability of the prepared products with a pH range of approximately 5.9 to 6.5 and TBARS ranging from 1.58 to 4.89 mg kg-1. It was observed that the garlic extract added to the meatballs did not influence (p<0.05) the WHC and PPC. The refrigerated meatballs combined with the chitosan coating revealed porous microstructures, while the coating alone presented a more continuous, homogeneous surface with little dispersion and porosity, validating the natural film when analyzed by SEM. The fatty acid analysis of the meatballs without additives detected saturated and unsaturated lipid components, as well as palmitic, linoleic, and eicosanoic acids. Therefore, we concluded that the chitosan-coated meatballs with garlic extract presented greater microbiological safety and stability under refrigeration, maintaining their physicochemical characteristics within quality standards. Tipo: Tese