INNOVATIONS IN TILAPIA NUTRITION IN ISRAEL

This paper summarizes research regarding feeding of tilapia in the Int ensive Fishculture Station at Ginosar during 1990-7. Results of resear ch in six major subjects are reported. Experiments with all-vegetable feeds indicate that fish meal can be completely replaced by supplement ing the feed with mineral phosphorus. There was an advantage to using feed with a 35% protein level and a lysine:protein ratio of 4.6-4.8%. Vitamin supplementation in feeds for tilapia during the fattening stag e had a positive effect on survival but did not seem to affect fish gr owth. Two experiments in feeding with extruded feed showed that floati ng pellets performed better than sinking pellets with the same composi tion. An experiment in feeding tilapia in low water temperatures showe d that consumption by tilapia in winter storage was affected by daily changes in water temperature and seasonedtemperature changes in differ ent ways throughout the storage period. In the low temperature of 16 d egrees C, tilapia of 100 g did not consume the offered feed. The ideal protein level and feeding rate for tilapia fingerlings of 0.5-13 g we re determined. Supplementation of fats to the feed for tilapia fingerl ings of 13 g did not improve fish performance. Actual feeding practice s, based on the results of our research, are described.