No synergistic effects by the dietary supplementation of ascorbic acid, α-tocopheryl acetate and selenium on the growth performance and challenge test ofEdwardsiella tardain fingerling Nile tilapia,Oreochromis niloticusL.

Abstract

To investigate the potential synergistic effects of dietary ascorbic acid (AA), α‐tocopheryl acetate (TA) and selenium (Se) supplementation above minimum requirement levels on the growth performance and disease challenge of fingerling Nile tilapia, Oreochromis niloticus L., five experimental diets were formulated: control (150 mg AA, 100 mg TA and 0.2 mg Se per kg diet), excessive ascorbic acid (eAA) (2000 mg AA, 100 mg TA and 0.2 mg Se per kg diet), excessive α‐tocopheryl acetate (eTA) (150 mg AA, 240 mg TA and 0.2 mg Se per kg diet), excessive selenium (eSe) (150 mg AA, 100 mg TA and 0.5 mg Se per kg diet) and excessive all (eALL) (2000 mg AA, 240 mg TA and 0.5 mg Se per kg diet). Experimental fish averaging 2.9 were randomly distributed in each aquarium as a group of 40 fish with total weight 116±2.9 g (mean±SD). Each diet was fed on a dry‐matter basis to fish in three randomly selected aquaria at a rate of 4–8% of total body weight daily. After 10 weeks of the feeding trial, fish fed eAA, eTA and eALL diets had significantly higher weight gain, feed efficiency ratio, protein efficiency ratio and specific growth rate than fish fed eSe and control diets (P<0.05). There was no significant difference among fish fed five experimental diets in cumulative mortalities when fish were challenged with Edwardsiella tarda at the end of the experimental period. These results indicate that sufficient supplementation of dietary AA or TA had positive effects on growth performance, but there was no synergistic effect of excessive dietary AA, TA and Se supplementation on growth performance and disease resistance to E. tarda in fingerling Nile tilapia.

Protective effect of dietary vitamin E against fungicide copperoxychloride stress on Nile tilapia, Oreochromis niloticus (L.), fingerlings

“…These results are similar to those reported by, Kim et al (2003) who mentioned that Nile tilapia fed diet supplemented with 150 mg vit.E had significantly (P \ 0.05) higher growth performance than those fed the control diet. Also, Galaz et al (2010) noted that dietary inclusion of vit.E significantly influenced growth performance and feed utilization of the juvenile parrot fish (Oplegnathus fasciatus).…”

Selênio orgânico na alimentação de matrizes de tilápia-do-Nilo (Oreochromis niloticus)

“…Os seguintes parâmetros foram avaliados nas larvas: sobrevivência, ganho de peso e conversão alimentar aparente. As médias dos parâmetros avaliados mantiveram-se dentro dos padrões recomendados para a espécie nas duas fases de criação (KUBITZA, 2000).…”

“…Micronutrientes, como vitaminas e minerais, são essenciais para o crescimento normal, reprodução e saúde dos peixes (KIM et al, 2003). No entanto, as exigências em minerais das diferentes espécies de peixes tropicais ainda se encontram defasadas.…”

“…Muitos dos problemas encontrados durante os primeiros dias de criação das larvas estão diretamente relacionados ao regime alimentar dos reprodutores. Por isso, técnicas de manejo e nutrição que melhorem parâmetros como frequência de desova, quantidade de ovos, taxa de eclosão e desempenho zootécnico das larvas devem ser estudados.Micronutrientes, como vitaminas e minerais, são essenciais para o crescimento normal, reprodução e saúde dos peixes (KIM et al, 2003). No entanto, as exigências em minerais das diferentes espécies de peixes tropicais ainda se encontram defasadas.…”

Influence of levels and forms of selenium associated with levels of vitamins C and E on the performance, yield and composition of tilapia fillet

“…Diet formulation enriched with vitamin C and E and selenium increases weight gain in tilapia (O. niloticus) (KIM et al, 2003) and increases selenium concentration in the muscle tissue of some species (BUCKLEY, 2000). However, there are few studies on the effects of nutrients on the performance, carcass yield, and chemical composition of tilapia fillets.…”