This study evaluated the effect of feed supplementation (at doses of 0, 50, 100, 150, and 200 mg/kg) with SALUTO®, a microencapsulated blend of essential oils including carvacrol, cinnamaldehyde, 1,8-cineol, and pepper oleoresin, in Nile tilapia (Oreochromis niloticus) broodstock on reproductive and growth parameters during the initial phase of rearing. The growth parameters, somatic indexes and gonadal and hepatic parameters were analyzed. Quantitative parameters of growth, ovary fat and crude protein were not affected by supplementation of the additive. However, an increase in crude protein in the female liver was observed in correlation with increased essential oil levels. The female hepatosomatic index was also correlated with supplementation of essential oils. Feeding Nile tilapia broodstock diets containing an essential oil compound (SALUTO®) affects only the females, promoting an increase in liver protein inclusion and hepatosomatic index without impairing performance.

This study was carried out to evaluate the influence of different levels of digestible energy and digestible protein in diets of Nile tilapia (Oreochromis niloticus) broodstock on offspring growth during sex reversal stage. A total of 2,700 post-larvae (8.2±0.001 mg) derived from breeders fed nine diets with distinct levels of digestible protein (28, 34 and 40% DP) and digestible energy (2,800; 3,400; and 4,000 kcal DE.kg-1) were stored in twenty-seven 70 L tanks. After 30 days of growth, their average final weight (AFW, g), average weight gain (AWG, g), final standard length (SL, cm), condition factor (CF), specific growth rate (SGR, %/day), stock uniformity (UNI, %), survival (SUR, %) and sex reversal rate (SRR, %) were measured. Although female nutrition is thought to influence the performance or quality of progeny during early life stages, no influence of diets supplied to broodstock was detected on any parameter. Nonetheless, the offspring presented commercially satisfactory growth rates. Thus, diets containing 28% of digestible protein and 2,800 kcal of digestible energy.kg of diet-1 can be used to feed Nile tilapia broodstock without jeopardizing offspring performance during the sex reversal phase.

Neste trabalho, avaliou-se o coeficiente de digestibilidade aparente da matéria seca, proteína bruta e a energia digestível de seis alimentos (raspa de mandioca, grão de sorgo, feno de atriplex, feno de gliricídia, feno de leucena e resíduo de vitivinícola) disponíveis no semiárido brasileiro, para a tilápia rosa. As rações foram marcadas com 0,1% de óxido crômico III. Utilizaram-se seis caixas circulares contendo 1000 litros de volume útil. Em cada caixa foi colocada uma gaiola circular de tela plástica, com 20 peixes cada (peso inicial de 80g). Os peixes foram arraçoados diariamente, três vezes ao dia. Para a coleta das fezes, cada gaiola foi colocada no início da noite em cubas de fibra de vidro cônicas com capacidade de 250L. O coeficiente de digestibilidade aparente dos ingredientes testados foi calculado com base no teor de óxido crômico III nas amostras de fornecidos e fezes, por análise de espectrofotometria de absorção atômica. Dentre os alimentos avaliados, os melhores valores de CDA para a MS foram referentes à raspa de mandioca e ao sorgo. Os melhores valores do CDA para a PB foram referentes à raspa de mandioca, sorgo e feno de gliricídia. O alimento avaliado com melhor valor de energia digestível foi o feno da atriplex.

This study evaluated the apparent digestibility coefficient of dry matter, crude protein and digestible energy (Kcal kg-1) for six ingredients (cassava chips, sorghum grain, atriplex hay, gliricídia hay, leucaena hay and wine residues) available in Brazilian semi-arid for pink tilapia feed. The feed were stained with 0.1% of chromic oxide III. A total of six circular tanks containing 1000 liters of volume were used. In each one was placed a circular cage of plastic screen with 20 fish each (initial weight of 80g). The fish were hand fed daily 3 times a day. To collect feces each cage was placed in the evening in conical 250L fiberglass tanks. Apparent digestibility of the ingredients tested was calculated based on the content of chromic oxide III in the samples offered and in the feces by atomic absorption spectrophotometry to the nutrient feed and feces, according to standard procedure. Among ingredients evaluated the best CDA values for MS were to cassava chips and sorghum. The best CDA values for CP were to cassava chips, sorghum and gliricidia hay. Atriplex hay was the ingredient with better digestible energy value.