Desempenho e morfologia hepática de juvenis de tilápia-do-nilo alimentados com dietas suplementadas com metionina e colina

Abstract

Resumo -O objetivo deste trabalho foi avaliar os efeitos da metionina e colina sobre o desempenho produtivo e a morfologia do fígado de tilápia-do-nilo. Durante 87 dias, 160 peixes da linhagem Supreme, com peso vivo médio inicial de 77±0,8 g, distribuídos igualmente em 16 tanques de 1.000 L cada, foram cultivados em sistema com recirculação de água. Os peixes foram alimentados com rações, peletizadas, três vezes ao dia, até saciedade aparente. Foram utilizadas quatro rações com 33% de proteína bruta e 3.000 kcal kg -1 de energia digestível: controle, sem suplementação; suplementação com 3.000 mg kg -1 de metionina; com 2.000 mg kg -1 de colina; com 3.000 mg kg -1 de metionina e 2.000 mg kg -1 de colina. Não foi observado efeito do fornecimento de metionina ou colina sobre o ganho de peso diário, conversão alimentar, rendimento de filé, índice hepatossomático e gordura visceral. Os peixes alimentados com dietas suplementadas com colina e metionina tiveram menor teor de gordura nos filés e redução de inclusões lipídicas no tecido hepático. A suplementação com colina e metionina não afeta o desempenho produtivo de juvenis de tilápia-do-Nilo, mas a colina tem ação na utilização do lipídio hepático, evidenciada pela redução de inclusões lipídicas.Termos para indexação: Oreochromis niloticus, aminoácido, fígado, músculo, peixe, vitamina. Performance and hepatic morphology of Nile tilapia juveniles fed methionine and choline supplemented dietsAbstract -The objective of this work was to evaluate the effects of methionine and choline on the productive performance and on the liver morphology of Nile tilapias. During 87 days, 160 Supreme strain fish, with average weight of 77±0.8 g, equally distributed in 16 tanks with 1,000 L each, were cultivated in a recirculating water system. The fish fed on pelleted diets three times a day until apparent satiation. Four diets with 33% crude protein and 3,000 kcal kg -1 digestible energy were used: control, without supplementation; supplemented with 3,000 mg kg -1 methionine; with 2,000 mg kg -1 choline; with 3,000 mg kg -1 methionine and 2,000 mg kg -1 choline. No effects of methionine or choline supplements were observed on daily weight gain, feed conversion, fillet yield, hepatosomatic index and visceral fat. Fish fed on diets supplemented with choline and methionine had lower fat content in the fillets and reduction of lipidic inclusion in the hepatic tissue. Choline and methionine supplementation does not affect productive performance of Nile tilapia juvenile; however, choline has an important action for hepatic lipid utilization, as evidenced by the reduction of lipidic inclusions.

Choline Alleviates Disorders of Lipid Metabolism in Hybrid Grouper (♀ Epinephelus fuscoguttatus × ♂ E. lanceolatus) Caused by High-Lipid Diet

“…However, in the present study, FW, WGR, and SGR tended to increase and then decrease with increasing choline concentration, but there was no significant difference. This is in agreement with the findings of red drum (Sciaenops ocellatus) [35], giant grouper (Epinephelus lanceolatus (Bloch)) [36], Nile tilapia (Oreochromis niloticus) [37], and black seabream (Acanthopagrus schlegelii) Jin et al [14]. And the reason for this difference may be that the lipid content of feed meets the requirement of grouper or the 8-week breeding cycle is not long enough.…”

<b>Digestible protein requirement for Nile tilapia fed with rations based on soybean meal and corn

“…The average dissolved oxygen in experimental tanks was equal to 6.9 ± 1.5 mg L At the end of the experiment, the fish were anesthetized (eugenol 75 mg l -¹) (Moreira, Teixeira, Carreiro & Moreira, 2010), weighed and measured (height, width, length and head) individually for the assessment of body parameters, chemical composition of the carcass and liver histology. In each experimental unit three animals were selected and randomly slaughtered to assessment of body yield parameters and histological evaluation (Vicentini et al, 2005) For the study of the morphology and integrity of the hepatic tissue, the procedures described by Graciano, Natali, Vidal, Michelato, Righetti and Furuya (2010) The final results of the evaluated parameters were submitted to variance analysis with significance level of 5% and in the case of statistical difference were applied regression analysis, using the SAEG program. vit.…”

Amino acid digestibility of animal protein ingredients for bullfrogs in different phases of post-metamorphic development

“…Some EAAs are interrelated with other corresponding analogues within the same group, as is the case of methionine and cysteine, which belong to the sulphur‐containing amino acids. The supply of adequate amounts of dietary cysteine can prevent the trans‐sulphuration of methionine and spare it for other metabolic pathways (Lovell ; Gatlin ; Graciano, Natali, Vidal, Michelato, Righetti & Furuya ).…”