No abstract

No abstract

To determine the dietary protein and energy requirements of juvenile largemouth bass, 1350 feed-conditioned ®shes (average weight 14.46 0.81 g) were stocked in ninety 60-L cages, set up in 1000-L tanks at three cages/tank, and fed for 64 days with a dry, extruded feed containing six levels of crude protein (CP) (340±540 g kg ±1 , with increases of 40 g kg ±1 ) and ®ve levels of energy (150.7±171.7 kJ g ±1 feed, with increases of 5.2 kJ). The trial was set up in a 6´5 factorial, completely randomized design (n 3). Weight gain (WG), daily feed consumption (DFC), feed conversion rate (FCR), protein eciency ratio (PER), speci®c growth rate (SGR), protein and energy retention were recorded and evaluated. There was no interaction between feed energy and protein levels with all parameters evaluated. Data analysis by the broken line method showed that the minimum dietary requirement for maximum daily weight gain of 8.0 g kg ±1 is 435.9 g kg ±1 CP; the best feed conversion ratio (1.04:1) was attained with a minimum of 448.2 g kg ±1 CP; a minimum of 162.1 kJ g ±1 ; DFC was reduced as dietary protein and energy levels increased; dietary levels of 460±500 g kg ±1 CP led to best PER (1.665); best values for protein (33.14 g 100 g ±1 ) and energy (26.87 g 100 g ±1 ) retention were observed for ®sh feeding on the 420 g kg ±1 CP ration. Limits of energy to protein ratio to feed largemouth bass are 25.01 and 26.89 mg protein kJ ±1 , enabling feed conversion ratios of 0.96±1.10. KEY WORDS 1 640.6 g kg )1 crude protein;11.59 g 100 g )1 total lipids. 2 Units kg )1 of diet: Mn 40 mg; Fe100 mg; Zn 100 mg; Cu10 mg; Co 1 mg; I 1.5 mg; Se 0.45 mg; vitamin A 36 000 UI; pyridoxine 9 mg; vitamin D 3 4500 UI; vitamin E 150 UI; vitamin B 12 90 mcg; thiamin 6 mg; ribo£avin 18 mg; vitamin K 3 4.5 mg; folate 9 mg; biotin 0.6 mg; pantothenic acid 30 mg; niacin 90 mg; vitamin C 346 mg. 3

Five isonitrogenous diets formulated to contain 470 g kg−1 of crude protein, five different levels of crude lipids (190, 210, 230, 250 and 270 g kg−1), five different levels of carbohydrates (178, 155, 158, 125 and 110 g kg−1) and gross energy (21.2, 21.6, 22.4, 22.8 and 23.2 MJ kg−1) were used to investigate the effect of dietary lipid levels on performance and carcass composition of the surubim, Pseudoplatystoma coruscans (Agassiz). Triplicate groups of 11 fish with an average individual body weight of 5.1 ± 0.2 g were randomly assigned to 15 net cages and fed each test diet twice a day to apparent satiation for 64 days. At the end of the trial there were no significant differences in feed consumption or fish performance. No differences (P > 0.05) were observed in the lipid content of fish carcass and liver. On the contrary, visceral lipid increased (P < 0.05) with the increase in dietary lipid level. Protein and energy retention efficiencies were not significantly affected (P > 0.05) by the dietary lipid and carbohydrate levels. The results of this trial suggest that increasing dietary lipid levels from 190 to 270 g kg−1 did not improve growth performance or protein sparing and caused an undesirable increase in the visceral lipid content of surubim fingerlings.

No abstract

Mangrove oysters, Crassostrea rhizophorae were collected at the mangrove of " Barra de Guaratiba" district, Rio de Janeiro, Brazil, with

No abstract

RESUMO: O objetivo deste trabalho foi avaliar alterações nas formas de reserva de energia na carcaça de juvenis de "black bass" (14,46 ± 0,81 g de peso vivo). Peixes condicionados a aceitar alimento artificial foram estocados em 90 gaiolas de volume 60 L alojadas em caixas de 1.000 L em laboratório com condições ambientais controladas, e alimentados por 64 dias com rações extrusadas com níveis de proteína variando entre 34 e 54% (incrementos de 4%) e teores de energia digestível variando de 3.600 a 4.100 kcal kg -1 de alimento (incrementos de 125 kcal kg -1 ). Foram analisados as variáveis de ganho de peso, consumo alimentar diário, relação hepato-somática, relação víscero-somática, deposição protéica e energética, glicogênio tecidual hepático e lipídio visceral. Não houve interação (P > 0,05) entre níveis de proteína e energia para os parâmetros avaliados. Os níveis de proteína e energia digestível dietética que garantiram melhor desempenho foram 42% e 3.850 kcal kg -1 , respectivamente. Dietas com teores médios de 42% de proteína bruta, induziram um alto acúmulo de glicogênio hepático (P < 0,0442), assim como aumento da relação hepato-somática (P < 0,0001), mostrando alta eficiência no acúmulo de energia prontamente utilizável bem como melhor capacidade de retenção dos nutrientes, quando os níveis de carboidratos foram inferiores a 30% na ração. O aumento dos níveis de energia das dietas, através da inclusão de óleo nas rações, induziu aumentos significativos no acúmulo total de lipídios na carcaça quando as médias eram agrupadas por níveis de energia, e induziu acúmulo de lipídios nas vísceras para os agrupamentos de médias tanto por teor de proteína (P < 0,0001) como de energia dietética (P < 0,0021). Palavras-chave: Micropterus salmoides, proteína, energia, glicogênio, lipídio PROTEIN AND ENERGY RETENTION BY JUVENILE LARGEMOUTH BASS Micropterus salmoidesABSTRACT: To determine dietary protein and energy retention of juvenile largemouth bass one thousand, three hundred and fifty feed-conditioned fish (average weight 14.46 ± 0.81 g) were stocked in 60-L cages set up in 1,000 L containers, and fed for 64 days with a dry, extruded feed containing varying levels of crude protein -CP (34, 38, 42, 46, 50 and 54%) and energy (3,600 to 4,100 kcal kg -1 feed, with increases of 125 kcal kg -1 ). The trial was set up in a totally randomized 6 x 5 factorial design (n=3). Data on weight gain, daily feed consumption, hepatosomatic index, viscerosomatic index, nutrient protein, energy retention, liver glycogen and visceral fat were evaluated. There were no interaction effects (P > 0.05) between feed energy and protein levels in respect to all evaluated parameters. Best performance was attained with levels of 42% CP and 3,850 kcal kg -1 in the diets, a condition which resulted in higher levels of liver glycogen (P < 0.0442) and higher hepatosomatic indexes (P < 0.0001) usually when diets presented less than 30% starch. Higher levels of dietary lipid induced significant increases in whole body lipids considering dietary energ...