EFFECT OF FEED FREQUENCY ON TILAPIA FINGERLINGS UNDER BIOFLOC SYSTEM

Good feed management minimizes nutrient inputs into pond water and is an important aspect of water quality management in fish farming. However, few experiments have been conducted to validate the alleged superiority of feed management practices for tilapia culture under bioflocs system. Feeding frequency is an integral part of a feed management.  The objective of these study is to determine the effect of feeding frequency under biofloc system on tilapia survival and growth in zero-water exchange culture tanks or bioflocs systems.

Nile tilapia fingerlings were purchased from a commercial tilapia hatchery, village No.12, El-Hamoul province, Kafr El-Sheikh Governorate, Egypt. Fish were healthy and free of parasites. Five fish groups (initial body weight 7.9 g ± 0.03 were stocked into each of twelve 55-l tanks (20 fish per tank). Fish were held in a zero-exchange system filled with well water for eight weeks and fed a commercial diet (30% crude protein) at 5% of their body weight per day in the first month and 4% in the second month. During the experiment, five feeding frequencies were evaluated with three replicates per treatment. Treatments were once T1 (08:00), twice T2 (08:00, 16:00), three times T3 (08:00, 12:00, 16:00), four times T4 (08:00,10:30, 13:00, 16:00) and five times T5 (08:00, 10:00, 12:00, 14:00, 16:00) per day. Fish were fed six days a week. Total ammonia, nitrite, nitrate, and pH were within acceptable limits. Data were analyzed as a one-way ANOVA using SPSS program. Means were separated using Duncan's multiple range test. The results indicated that frequency of 2 feedings/day was the most adequate for feeding tilapia under biofloc system. This work was supported by Science & Technology Development Fund (STDF), Egypt under grant no 5671.