Feed Peas in diets for shrimp tilapia and milkfish - Northern Pulse ...

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Water temperature for the whole duration of experiment 1 ranged from 22-27°C, being at the lower rangefor most of the days. Dissolved oxygen in the morning before partial water change ranged from 3.5-6.2 mg l -1 . The total NH 3 -N ranged from 0.63-2.39 mg l -1 and pH, 7.7-7.9. In experiment 2, water temperature for thefeeding trial with the CLSU strain of tilapia was 23-27°C; pH, 7.4-8.1; total NH 3 -N, 0.21-2.42 mg l -1 . For thefeeding trial using the BFAR strain, water temperature also ranged from 23-27°C; pH, 7.6-8.7; and totalNH 3 -N, 0.28-1.74 mg l -1 . For each sampling time, water quality was similar among treatments.4. Biochemical analysesSamples of feed ingredients, experimental diets, and some fish at stocking and during harvest wereobtained for proximate analysis by standard methods (AOAC, 1990). At the end of the each feeding trialand after a 24-hour fasting, fish samples were obtained and dissected. The appearance of the fish and theinternal organs were examined visually for any abnormality. Other samples of fish that received the dietswhose digestibility was determined were subjected to cold shock, weighed and kept frozen until they wereprocessed further. The fish samples were then autoclaved, homogenized, dried in a vacuum oven at 60°C,and ground for analysis.5. Digestibility measurements5.1. Digestibility of feed peas as ingredientThe apparent dry matter digestibility (ADMD) and crude protein digestibility (APD) of feed peas asingredient were measured indirectly using chromic oxide (Cr 2 O 3 ) as external indicator (Cho et al., 1982;Spyridakis et al., 1989). The reference diet for the measurement of digestibility of feed peas was the sameas the control diet used in experiment 1 (Table 1), except that 1% Cr 2 O 3 and 1% carboxymethylcellulose(CMC, binder) replaced some amounts of the filler. The test diet contained 70% reference diet and 30%feed peas, following the method of Cho et al. (1982). It also contained 1% Cr 2 O 3 and CMC.Each of the diets was fed to tilapia in three replicate tanks stocked with 10 juvenile tilapia (37.96 ± 0.42 gfish -1 ). The tilapia came from the same source as those used in experiment 1. The fish were fed at 5-8% offish biomass daily with two feedings a day (0830 and 1430h). Water temperature ranged from 24-26°C.A modified Guelph system (Cho et al., 1982; Eusebio and Coloso, 2000) was used in the digestibility trials.Each conical fiberglass tank (250 L capacity) was provided with filtered, flow-through water. Flow rate of thewater was 780-850 ml min -1 . Water passed through a fecal decantation column into an attached clearplastic bottle where the fecal materials settled until collected. The tanks and the fecal collection apparatuswere cleaned twice daily before feeding in the morning and 2 hours after feeding in the afternoon.Collection of feces released from 1730-0730 h started after a 5-day initial feeding and lasted for 25consecutive days. Fecal material were carefully rinsed with distilled water and stored in a freezer to retardbacterial decomposition. Samples were pooled and freeze-dried. Dry fecal samples and test diets wereanalyzed for Cr 2 O 3 (Carter et al., 1960) and crude protein (AOAC, 1990).5.2. Digestibility of diets containing feed peasThe digestibility of diets with 0, 10, 30 and 50% replacement of fishmeal protein (Table 1), as well as dietswith 0, 15, 25 and 35% replacement of plant protein by feed peas (Table 2), was determined in tilapia inseparate trials. Celufil (filler), starch, and rice bran were adjusted to accommodate 1% Cr 2 O 3 and the binderin the diets. Each feeding period, including the 5-day adjustment with the marked diets, lasted for 30 days.Fish used in determining the digestibility of the two sets of diets containing feed peas were bigger tilapiajuveniles (CLSU strain, 82.7+9.3 g) that came from the same batch used in the growth trial (experiment 2).The digestibility tank system, and the procedure for collection of feces and processing of samples were thesame as in the previous digestibility trial for peas as an ingredient. The apparent digestibility for dry matterand crude protein in the diets was likewise computed using the formula of Spyridakis et al. (1989).6. Statistical analysisData on body weight (weekly and biweekly), weight gain, total length, survival, FCR, PER, carcass proteinand ash, and digestibility coefficients were analyzed by ANOVA using the General Linear ModelsProcedure by SAS for PC (SAS Institute Inc., 1991). When significant difference among treatments wasdetected at P
However, weight gain was highest at the 10% fishmeal protein substitution, or 12.7% feed pea in the diet.The FCR values for the duration of the experiment, as well as the PER, did not differ significantly (Table 3).Survival rates of tilapia in replicate tanks within treatment were highly variable; mean survival rates did notdiffer significantly among treatments (P>0.05). Mortality was caused by the aggressive behavior of the maletilapia in the small rearing tanks and was not treatment-related.In experiment 2, body weight of the CLSU strain of tilapia at weekly or biweekly intervals did not differsignificantly among treatments (P>0.05). The final weight gain and length increment, as well as the FCRand PER, did not differ significantly (Table 4). Survival rate was 100% in all tanks. Likewise, the BFARstrain of tilapia in experiment 2 did not show significant differences in body weight during each sampling, orweight gain and total length increment over a 12-week period (Table 5). Moreover, the FCR and PER didnot differ significantly among treatments. Survival rate in all tanks was also 100%.Carcass protein of fish from four dietary treatments in experiment 1 showed no significant differences(P>0.05) (Table 6). However, body ash increased significantly in fish fed diets with 37.5 and 63.3% feedpeas (or 30 and 50% fishmeal protein substitution). The fish fed with 10% fishmeal protein substitution(12% feed peas) had the highest carcass lipid. Fish in all other treatments had similar carcass lipid. Inexperiment 2, carcass protein as well as body ash differed significantly among treatments (Table 6), but notrend could be established in relation to fish growth and digestibility of the diets. However, as the dietaryfeed peas in the plant-based diets increased and the dietary lipid decreased (Table 2), carcass lipiddecreased (Table 6).There was no visible adverse effect of dietary peas on feeding behavior and the appearance of the fish andthe internal organs. The three tilapia strains used in the feeding trials readily accepted the diets containingfeed peas and consumed almost the same amount of feed in relation to their body weight (about 5% of fishbiomass). Visual examination at the end of each trial revealed that the tilapia were generally lean. Fish liverdid not appear fatty and only few adipose tissues were visible in the body cavity.The apparent dry matter digestibility (ADMD) of feed peas as ingredient was 69.3+1.8% and proteindigestibility (APD) was 87.2+2.0%. The ADMD coefficients for some fishmeal-based diets used inexperiment 1 significantly increased with increasing level of feed peas (Table 7). The APD for the dietstested were all high, exceeding 90%. Although the absolute differences were small for practical purposes,the APD of the control diet (without pea) was significantly higher than that of diet with 12.7% feed pea, butdid not differ significantly from that of diets with 37.5% or 63.3% feed pea (Table 7). The plant-based dietsin which digestibility coefficients were determined also showed a significant increase in ADMD when feedpea in the diet was 29.3% or more (Table 7). The APD coefficients of the plant-based diets were high(>90%), as in the fishmeal-based diets in experiment 1, and did not differ significantly among treatments.DiscussionThe three feeding trials consistently demonstrated that feed peas could be incorporated in tilapia diets at awide range of levels to replace fishmeal protein or other plant proteins without affecting fish growth, feedefficiency, and survival. The FCR values obtained for all diets in the feeding trials were higher than theexpected values (about 2) and, consequently, the PER values were fairly low. These could be attributed tothe water temperature during the experiments, being lower than the optimum (28-31°C) for the tilapia(Luquet, 1991), and to some losses in the collection of the uneaten feed. Because the indoor culture systemhad static water, the dissolved oxygen before partial water change in the morning sometimes dipped closeto the minimum level (3 mg l -1 ) for tilapia (Luquet, 1991). Nevertheless, the tilapia in two of three feedingtrials had 100% survival. The growth response of tilapia to diets with peas in the different feeding trials wasnot affected by the dietary levels of feed pea.In general, carcass protein, lipid and ash did not indicate any adverse effect of increasing dietary feed pea.Although growth did not differ significantly among treatments, significant differences in protein wasobserved in fish fed plant-based diets, but not in fish fed the fishmeal-based diets. Moreover, carcass lipidof the tilapia (CLSU strain) fed plant-based diets decreased with the increase of feed peas in the diet. In acompanion study, feeding of milkfish (Chanos chanos) with varying dietary feed peas caused significantdifferences in growth but it did not influence carcass composition (I. Borlongan, personal communication2002). Similarly, two levels of peas in the diets (20 and 40%) did not affect carcass protein and ash inEuropean sea bass but lipid was significantly lower in fish given diet with 40% pea (Gouveia and Davies,1988).Although high amounts of feed peas could be used in tilapia diets, the actual amount that would beincorporated in practical applications will be influenced largely by the cost of the peas in relation to the cost14
Page 2 and 3: Final Project ReportTitle:Utilizati
Page 4 and 5: SUMMARYThis report summarizes the r
Page 6 and 7: Utilization Of Feed Pea, Pisum Sati
Page 8 and 9: were thawed and pooled prior to fre
Page 10 and 11: Table 3Composition of reference and
Page 12 and 13: Table 10Percent recovery of experim
Page 14 and 15: Feed Pea (Pisum Sativum) As An Alte
Page 18 and 19: of competing protein sources. The d
Page 20 and 21: Table 4Mean initial weight and tota
Page 22 and 23: Hanley, F., 1987. The digestibility
Page 24 and 25: experimental diets are presented in
Page 26 and 27: The results of the digestibility tr
Page 28 and 29: Table 3Composition (g/100g diet) of
Page 30: USA Dry Pea& Lentil CouncilHead Off

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