TEDE Collection:

Análise da viabilidade técnico econômica na criação de tambaqui (Colossoma macropomum) em tanques escavados em Rondônia, Brasil

Mon, 03 Nov 2025 00:00:00 GMT

Title: Análise da viabilidade técnico econômica na criação de tambaqui (Colossoma macropomum) em tanques escavados em Rondônia, Brasil Autor: Silva, Ricardo Cezar Alves Vieira da Primeiro orientador: Signor, Altevir Abstract: Aquaculture has emerged as one of the most dynamic agro-productive activities worldwide, contributing to food security, income generation, and regional development. In Brazil, fish farming has gained increasing importance, with tambaqui (Colossoma macropomum) standing out as the main native species cultivated, especially in the Amazon region. The present study aimed to analyze the technical and economic feasibility of tambaqui farming in earthen ponds in the state of Rondônia, evaluating productive and financial performance indicators, as well as comparing management strategies, with emphasis on partial harvesting. For this purpose, the research was conducted on a fish farm of 125.2 hectares, located in Cujubim (RO), consisting of 34 grow-out ponds and 11 nursery ponds. Data collected between 2018 and 2022 were analyzed, including production costs, feed prices, revenues, and zootechnical indicators. The economic analyses included the calculation of Net Present Value (NPV), Internal Rate of Return (IRR), Payback Period, Gross Margin, Profitability Index, and Break-even Point, complemented by sensitivity simulations. The results showed that the initial investment was R$ 7,499,693.43, with an annual operating cost of R$ 6,219,530.54. Feed accounted for 82.4% of total costs. The average productivity reached 7,223.99 kg/ha/year, with a gross margin of 9.10% and profitability of 8.33%. The financial analysis indicated a negative NPV (-R$ 30,337,583.19) and an IRR of -6.11% for a minimum attractive rate of 10%, demonstrating economic unfeasibility under current conditions. However, the sensitivity analysis showed that a 10% increase in fish selling price (R$ 8.83/kg) would result in a positive NPV of R$ 18,814,111.43 and an IRR of 17.26%, making the activity economically viable. In the comparative study between management strategies, partial harvesting showed higher productivity (10,474.34 kg/ha) but higher costs and lower profitability (1.81%) compared to total harvesting (13.88%), which proved to be more economically efficient. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Tese

Influência do barramento de um rio neotropical sobre as comunidades de peixes, zooplâncton e a qualidade da água

Fri, 26 Oct 2018 00:00:00 GMT

Title: Influência do barramento de um rio neotropical sobre as comunidades de peixes, zooplâncton e a qualidade da água Autor: Orsi, Carlos Henrique Primeiro orientador: Baumgartner, Gilmar Abstract: Damming for purposes of electric energy production have been explored for several decades, with the rivers of the Neotropical region being very affected by such projects. In this study, we intend to evaluate the influence of damming Cantu river on fish and zooplankton communities and on the physical, chemical and biological characteristics of water quality, as well as to verify the relationship between communities and water quality before and after damming. The results showed that, after damming, fish and zooplankton communities were restructured, and that the parameters evaluated for water quality also showed differences and influence on the communities. The most influential characteristics were water temperature, transparency, turbidity and chlorophyll-a concentration. Therefore, we conclude that comparative studies between periods (pre and post damming) for reservoir formation purposes should be maintained to identify such changes and to promote mitigation measures to the impacts. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Tese

Diluentes contendo extratos vegetais para a criopreservação de sêmen de jundiá (Rhamdia quelen)

Fri, 05 Mar 2021 00:00:00 GMT

Title: Diluentes contendo extratos vegetais para a criopreservação de sêmen de jundiá (Rhamdia quelen) Autor: Pedreira, Ahiana Cassia de Oliveira Primeiro orientador: Bombardelli, Robie Allan Abstract: The aim of the present study was to maximize the use of cryopreserved semen of the species Rhamdia quelen collected from the reproductive peak and outside the breeding season, using different extracts of Eichornia crassipes and curcumin in the diluting solution, in order to assess the viability and yield of cryopreserved sperm. Thirty males (130.00 ± 3.47g) were used in the first trial and 20 males (153 ± 0.04g) in the second trial. The induced semen was collected, evaluated and homogenized to form composite samples. Then the semen was diluted in a solution containing 5% fructose, 5% powdered milk, 10% methanol, in the same diluent five different extracts were added: 0.75% ERA = aqueous root extract, 0.5% EAA = aerial aqueous extract, 0.5% EAFP = aqueous polar fraction extract (first test). The same procedure was applied in the second trial using 1% and 1.5% ERH = hydromethanolic extract of the root; 0.75% and 1% ERA = aqueous root extract; 0.5% and 1% ERAq = heated root extract; 1.25% and 1.5% EAH = aerial hydromethanolic extract; 0.5% and 1% EAA = aerial aqueous extract; 0.5% and 1% EAAq = heated aerial extract. After 30 days, the semen was thawed to evaluate the sperm movement, sperm quality, biochemistry and cryopreserved sperm yield. For fertilization, 20 females of R. quelen (191.00 ± 0.05g) were used in the first trial and 25 females (202.00 ± 0.09g) in the second trial. Then, the females were induced to ovulate and the oocytes were collected and fertilized using cryopreserved semen with the respective diluents. Fertilization, hatching and larval normality rates were evaluated. Diluents containing E. crassipes extracts improved (p <0.05) motility compared to the standard diluent in the two trials. They also improved (p <0.05) membrane morphology and integrity, using extracts of E. crassipes and curcumin. In the second trial, there was a reduction in lipid peroxidation using E. crassipes extracts. The effective yield and the effective dose were also improved with the use of E. crassipes extracts. Therefore, it is concluded that diluents containing extracts of E. crassipes and curcumin guarantee protection of sperm during cryopreservation, increase cell viability. In addition to improving semen yield outside the breeding season. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Tese

Pescado para alimentação escolar no Paraná: políticas públicas e análise territorial da sua produção

Mon, 08 Sep 2025 00:00:00 GMT

Title: Pescado para alimentação escolar no Paraná: políticas públicas e análise territorial da sua produção Autor: Miranda, Eva Barros Primeiro orientador: Feiden, Aldi Abstract: This dissertation analyzes the inclusion of fish in school feeding in Paraná, with emphasis on the role of the National School Feeding Program (PNAE) as a structuring public policy for food and nutritional security. The investigation combined literature review, document analysis, and empirical research across multiple scales. At the state level, data from FUNDEPAR (2015–2022) were examined, highlighting the historical predominance of breaded fish but also the recent appreciation of tilapia fillets, linked to the strong production base in western Paraná. In some microregions, fish has already surpassed other meats in the volume purchased, revealing its strategic potential for school menus. At the municipal level, 27 public procurement calls (2019–2025) were analyzed in dialogue with the Municipal Livestock Production data (IBGE). The results show significant presence of fish whenever animal protein is supplied, although territorial gaps and temporal fluctuations remain. Frozen tilapia was the most recurrent item, with formats adapted to the school public, such as fish balls. The study demonstrates that the inclusion of fish in school feeding is conditioned not only by production availability but also by the institutional, logistical, and pedagogical arrangements that sustain PNAE implementation in the state. Furthermore, it reveals a gap between state legal frameworks—which project the universalization of organic school meals by 2030—and the absence of specific sustainability criteria for animal proteins. It is concluded that fish already holds a significant position in Paraná’s school feeding and can be consolidated as a strategic food for more sustainable food systems, provided that public policies advance in aligning institutional consumption, regional production base, and sustainability guidelines. Publisher: Universidade Estadual do Oeste do Paraná Tipo do documento: Tese