الفهرس 
Geographical distribuBon of TilapiasOnly 14 pages are availabe for public view
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Abstract
This work was conducted in the Regional Laboratory for Food and Feed, Agriculture Research Center, Giza, Egypt.
The aim of this study is to evaluate the effect of feeding Nile tilapia (Oreochromis niloticus) on treated soybean products
Seven diets were tested as follow:
T1: 100 %soybean meal, control.
T2: 50 % of the soybean meal was replaced by extracted fall fat soybean seeds (EFFSB) +50 % soybean meal.
T3: 100% EFFSB.
T4: 50 % of the soybean meal was replaced by germinated soybean seeds (GSB) +50 % soybean meal.
T5: 100% GSB.
T6: 50 % of the soybean meal was replaced by germinated and heated soybean seeds (GHSB) +50 % soybean meal.
T7: 100% GHSB.
Results are summarized in the following
:
1. Survival rate
After 12 weeks of the experimental period, the highest survival rate was recoded by treatment 2 (97.78%) while the lowest was obtained by treatment 5 (51.11%).Differences among the experimental treatments were significant (P<0.05).
2. Feed and nutrients intake
The highest feed and nutrients (CP and EE) intake were shown in treatment T2 while the lowest ones were recorded in treatment T5
3. Digestibility experiment
The highest average apparent digestion coefficient of DM was obtained by the fish reared at T2 (78.19%) followed by T6 (77.02%) then T3 (76.42%). The lowest average apparent digestion coefficient of DM was obtained by T5 (52.88%).
The highest average apparent digestion coefficient of (CP) was obtained by the fish reared at T2 (83.42%) while followed by T6 (79.06%). The lowest average apparent digestion coefficient of (CP) was obtained by the T5 (35.69%).
The highest average apparent digestion coefficient of (EE) was obtained by the fish reared at T3 (84.52%), while the lowest average apparent digestion coefficient of (EE) was obtained by T5 (72.19%).
The results of the present experiment showed that replacing 50 % of the soybean meal by EFFSB improved the digestibility coefficient of a plant protein diet (T2) which in turn positively affected growth and feed conversion parameters.
4. Final average body weight
The EFFSB treatments resulted in higher values of average final body weight compared with the other treatments, whereas GSB treatments showed the lower values
5. Total weight gain
Treatment 2 gave the highest total weight gain while treatment 5 gave the lowest values.
6. Specific growth rate
The highest value of specific growth rate was recorded with in treatment 2 (3.10 % / day) while the lowest one was observed in treatment 5 (1.61 % / day).
7. Growth rate
Treatment 2 gave the highest growth rate while treatment 5 gave the lowest one
.
8. Feed conversion ratio (FCR)
The highest value (the worst) of FCR was recorded for treatment 5 (2.19g feed/ g gain) while the lowest value (the best) was recorded with treatment 2 (1.06 g feed/ g gain).
9. Protein efficiency ratio (PER) and protein productive value (PPV)
The highest value of (PER) was shown in treatment 2 (3.12) while the lowest was recorded for treatment 5 (1.53).
The highest PPV% was found in treatment 6 (17.46%) while the lowest one was recorded for treatment 5 (7.97%).
10. Economical efficiency
The lowest cost of producing kg fish gain (%) in the present study was obtained by treatment 2 (2.76 LE/kg fish gain) while the highest cost was recorded by treatment 5 (5.87 LE/kg fish gain).
11. Chemical composition of the whole fish:
Statistical analysis of crude protein percentages showed that treatment 1 (62.53 %) was significantly (P<0.05) higher compared with the other treatments.
Ether extract percentages indicated that treatment T3 (22.94%) gave the highest significant (P<0.05) value of fat percentages compared with the other treatments.
Ash percentages indicated that treatment T6 (17.17%) gave the highest significant (P<0.05) value of fat percentages compared with the other treatments.
CONCLUSION
from the previous results it can be conclude that germination of soy seeds without heating had minor effect on trypsin inhibitor which affected negatively the growth performance, feed utilization and carcass composition of tilapia fish when included in its diets. In addition, it could be concluded that the incorporation of extruded full fat soybean as a plant protein and energy source in growing Nile tilapia diet improved growth performance, digestibility, feed utilization parameters and economical efficiency compared to other tested treatments.