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Tilapia Diets (tilapia + diet)
Selected AbstractsEffects of photoperiod on growth and spawning efficiency of Nile tilapia (Oreochromis niloticus L.) broodstock in a recycling systemAQUACULTURE RESEARCH, Issue 12 2007Abdel-Fattah M El-Sayed Abstract This study was conducted to evaluate the effects of photoperiod on the growth, feed conversion ratio (FCR) and spawning performance of Nile tilapia (Oreochromis niloticus) broodstock. Duplicate groups of two males (66±3.04 g) and six females (50.5±1.58 g) were stocked in 0.4 m3 fibreglass tanks in a recirculating water system at a male:female ratio of 1:3. The fish were subjected to four photoperiod treatments: 24:0 light:dark (L:D), 18L:6D, 12L:12D and 6L:18D. Light intensity was kept constant at about 2500 lx throughout the study. The fish were fed a commercial tilapia diet (35% crude protein and 16.6 MJ GE kg,1) at a daily rate of 2,3% of tank biomass, twice a day, for 130 days. Males grew significantly faster than females under all photoperiod regimes. The best growth rate and FCR were attained at 18L:6D, followed by 24L:0D, 12L:12D and 6L:18D respectively. The number of eggs per female, number of eggs per spawn and number of spawnings per female were all significantly higher in the 12L:12D treatment than in all other photoperiod cycles. Interspawning intervals and days elapsed per spawn were also shorter in the 12L:12D treatment. The time to first spawning was slightly longer in the 24L:0D and 6L:18D than in 12L:12D and 18L:6D light phases. The 18L:6D and 6L:18D photoperiods produced the lowest spawning performance. It is concluded that a 12L:12D photoperiod regime should be adopted for maximum fecundity, seed production and spawning frequencies of Nile tilapia broodstock reared in intensive, recirculating systems. If maximum reproduction is desired, a near-natural day length photoperiod should be used. [source] Comparative growth performance of two Nile tilapia (Chitralada and Red-Stirling), their crosses and the Israeli tetra hybrid ND-56AQUACULTURE RESEARCH, Issue 11 2005Angela Aparecida Moreira Abstract Growth performance of two Oreochromis niloticus strains, Chitralada and Red-Stirling, their reciprocal crossbred and the Israeli tetra-hybrid ND-56 were assessed in net cages under on-farming conditions. Throughout 268 days of grow-out, the strains were weighed monthly and mortality, feed consumption and water quality were recorded. Ten rigid net cages (1.5 × 1.5 × 1.7 m) immersed in a 10 ha reservoir were linearly arranged near the reservoir outlet following a completely randomized design with two replicates for each treatment (strain). Each cage was stocked with 459 fish (120 fish m,3) and fed twice daily to apparent satiation with a commercial tilapia diet following the recommended feeding program. The final mean weights were higher for Chitralada (557.20 g) and the reciprocal crossbreds (522.95, 496.40 g) than those of Red-Stirling (421.90 g). All treatments outperformed the ND-56 tetra hybrid. Daily growth showed statistical differences between Chitralada (2.04 g) and Red-Stirling (1.52 g) but they were statistically the same when compared with the reciprocal crossbreds (1.90, 1.80 g). The relative growth ratios showed the same trend observed in the results for daily growth. The mean survival rate was 98%. The overall growth rate showed that crossbred performed as well as the parental lines. All crossbred progeny presented red colouration with variable pattern of black marks corroborating the dominant inheritance of the red trait in Red-Stirling strain. [source] Evaluation of Brewer's Waste as Partial Replacement of Fish Meal Protein in Nile Tilapia, Oreochromis niloticus, DietsJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2008Desale B. Zerai A 10-wk feeding trial experiment involving five different diets with increasing levels of brewer's waste (32% crude protein) was carried out to evaluate the use of brewer's waste in tilapia diets in place of fish meal. Growth performance was compared against a control diet formulated to have similar composition to a typical commercial diet. Four experimental diets replaced successively 25, 50, 75, and 100% of the fish meal protein with brewer's waste. The diets were isonitrogenous and isocaloric. Results indicated that weight gain did not differ significantly (P > 0.05) with up to 50% replacement. Feed intake and utilization were depressed at high levels of brewer's waste. In addition, methionine of high replacement level diets was low. The results of the digestibility trial demonstrated that the brewer's waste used in this study has an apparent digestibility coefficient for protein of 70%. It was concluded that 50% of the fish meal protein in a typical commercial diet could be replaced with brewer's waste with no adverse effect on growth and feed utilization for tilapia. [source] Nutritional evaluation of waste date fruit as partial substitute for soybean meal in practical diets of juvenile Nile tilapia, Oreochromis niloticus L.AQUACULTURE NUTRITION, Issue 3 2009M.S. AZAZA Abstract The potential of waste date meal (WDM; low-quality date palm, Phoenix dactylifera L.) as a carbohydrate source in formulated diets for Nile tilapia was evaluated. Four isocaloric-practical diets (15.7 kJ g,1) were formulated incorporating WDM at 0, 100, 200 and 300 g kg,1 levels as partial substitutes for soybean meal (SBM). These were designated D0 [284 g crude protein (CP) and 383 g carbohydrate (CHO) kg,1 diet], D1 (279 g CP and 446 g CHO kg,1 diet), D2 (207 g CP and 495 g CHO kg,1 diet) and D3 (175 g CP and 578 g CHO kg,1 diet). Each diet was fed to three replicate groups of 30 fish [20.20 ± 0.09 g (±SE)] for 75 days. No feed-related mortality was observed during the entire experimental period. Final body weight (FBW) and specific growth rate (SGR) in the different treatments were statistically not significantly different (P > 0.05). Protein efficiency rate (PER) was lowest in diet D0 and increased with decrease of SBM content (D1,D3). A significant increase in whole body lipid content was recorded in fish fed diets D2 and D3. Results showed that WDM could be a substitute for SBM up to 300 g kg,1 in practical Nile tilapia diets without compromising growth. [source] Replacement of soybean (Glycine max (L.) Merrill) meal by lupin (Lupinus angustifolius) seed meal in diet for juvenile tilapia (Oreochromis niloticus×O. aureus) reared indoorsAQUACULTURE RESEARCH, Issue 14 2003Y H Chien Abstract An 8-week trial was conducted to assess the feasibility of replacing soybean meal (SBM) by lupin seed meal (LSM) in simulated commercial diets for juvenile tilapia starting at 0.3 g. Of the dietary protein (26% crude protein), 3.45% was from fishmeal and the rest came from the vegetable protein sources. The protein source of the control (C) diet came mainly from SBM and none (0%) from LSM. For the other diets, 33%, 67%, or 100% of the SBM protein was replaced by protein from either whole or dehulled LSM. One further diet was used: AW100, where alkaloid of the whole lupin seed was reduced. Survival, growth, and feed performance were compared among seven orthogonal contrasts to determine the effects of replacing SBM with whole LSM or dehulled LSM, and of reducing the alkaloid content. No differences in survival were found among all contrasts. No differences in fish growth and feed performance were found between feeding diet C and the other six diets ((whole, dehulled) × (33, 67, and 100)). Dehulled LSM diets resulted in better growth and feed performance than the whole LSM diets. Partial replacement of SBM by either dehulled LSM or whole LSM in diets obtained better growth and feed performance than total replacement. The AW100 diet resulted in equal fish growth but better feed performance than the W100 diet. This study concluded that partial, but not total, replacement of soybean protein with lupin seed protein in juvenile tilapia diets resulted in better, or at least equal, growth and feed performance. Dehulling further enhanced the growth and performance of LSM. Alkaloid removal improved feed performance but not the growth. [source] | ||||||||||