Growth and Survival of Tilapia molobicus Hybrid (Oreochromis niloticus x Oreochromis mossambicus) Different Stocking Densities.

A 60 days experiment to determine the effect of different stocking densities on the growth and survival of Tilapia molobicus hybrid of (O. massambicus x O. niloticus). fingerlings in saltwater pond was conducted at the college of fisheries laboratory and research station, Brgy. Bawing, General Santos City experimental facilities. Tilapia molobicus with 8.2633g as initial weight were stocked. A complete Randomized Design (CRD) was used with three treatments: Treatment! with 25 pcs/m3, Treatment II with 50 pcs/m3, and treatment III with 75 pcs/m3. Each Treatment was replicated three times. Fish were fed with commercial feeds at sliding feeding rate of 10% for the first 30 days and 8% for the next 30 days, of their average body weight. Sampling of 50% of the total stock of each treatment was done every 15 days for a period of 60 days duration of the experiment.

The Highest mean body weight of the experimental animal was attained in Treatment I (25 pcs/ m3) which is 58.96g, followed by treatment II (50 pcs/m3) with 49.4g and treatment III (75 pcs/m3) with 43.86g. The Highest mean weight gain was obtained by fish in treatment I with 50.7g, followed by treatment II with 41.14 and lowest in Treatment III 35.6g. The fish in Treatment I obtained the highest mean daily weight gain 0.84g/day, followed by treatment II with 0.68g/day and Treatment III with 0.59g/day. Mean body weight, mean weight gain and mean daily, statistical analysis showed that among the treatments are significant difference.

The highest survival rate was obtained by fish in treatment I with 96%, followed by treatment II with 94% and treatment III with 92.67%. Statistical analysis showed significant difference among treatment means (P<0.05). when growth parameters were subjected to Duncan's Multiple Range test (DMRT), Treatment I is not significant to Treatment II and Treatment II is not significant to Treatment III but Treatment III is significant to Treatment I.

Better feed conversion ratio (FCR) was obtained by treatment I 1.96, followed by treatment II with 2.07 and treatment III with 2.23. Statistical analysis showed no significant difference among treatment means (P<0.05). temperature readings 28- 29.2, salinity 30-32 ppt, pH 7.3-7.9, dissolved oxygen 5.2-6.8 ppm and ammonia at 0.0 ppm. These ranges are found to be within the tolerable range of tilapia molobicus. Statistical analysis showed that Treatment III is not significant to Treatment II and Treatment II is not significant to Treatment I but Treatment I is significant to Treatment III.