Efeitos da temperatura no desempenho e na morfometria de tilápia, Oreochromis niloticus, de linhagem tailandesa

• Autor(a) principal: Maciel Junior, Alaor
• Data de Publicação: 2006
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1893
• topic: Tilápia; Desempenho; Estresse térmico; Tilapia; Performance; Heat stress; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL

A 55 days essay was accomplished in the Fish Nutrition and Production Laboratory the Department of Animal Science of the Universidade Federal de Viçosa, MG, with the objective of verifying the effects of the temperature on the productive performance, by means of zootechnical indexes and morphometry, of juvenile tilapias of Thai lineage. The fish, from a commercial fish farm, with initial weight of 0,835 ± 0,004 g, were distributed in 24 aquaria with 100l of capacities, with heating and supplemental aeration. The experimental design was entirely casualised, with four treatments, corresponding to test-temperatures: 20,0; 24,0; 28,0 and 32,0º C; six replicates and ten fishes/experimental unit. The used ration, with corn, soybean meal and corn gluten base, contained 29,0 % of digestible protein, 3.000 kcal of digestible energy and 3,44% of gross fiber. It has evaluated: the individual (GP) and the biomass of the aquarium (GB) weight gain, the apparent ration consumption (CRA) and the alimentary conversion (CAA), the specific growth (TCE) and protein efficiency (TEP) rates and the daily protein and of fat (TDP and TDG, respectively) deposition, the body composition (dry matter, gross protein and gross lipids), the hepatossomático (IHS), hepatovisceral (IHV) indexes and the Intestinal coefficient (CI), besides the alometric condition factor (K). The performance of the tilapias, as well as the morphometrics relationships were influenced by the temperature, being the best indexes between 28,0 and 32,0ºC. The mortality increased with the temperature elevation, however in the lowest temperatures, 20,0 and 24,0º C, in which the mortality was 0,00 and 1,67%, respectively, the performance was significantly worse than in the highest temperatures, what allows to conclude that the juvenile Thai tilapia presents better performance and morphometry at temperatures between 28,0 and 32,0º C.