IMPROVED GENETICS AND A NOVEL FEEDING STRATEGY FOR INCREASED GROWTH RATES OF NILE TILAPIA Oreochromis niloticus IN A RECIRCULATING AQUACULTURE SYSTEM

Brian K. Catanzaro
 
Pentair Aquatic Eco-Systems Inc.
2395 Apopka Blvd. Apopka, FL 32703
brian.catanzaro@pentair.com
 

A Nile tilapia growth trial was conducted at the Pentair Aquatic Eco-Systems Inc. World Aquaculture Technology Engineering Research center (PAES W.A.T.E.R). The trial evaluated growth performance of a genetically improved strain of tilapia in a state-of-the-art recirculating aquaculture system (RAS). A robotic delivery system allowed for precision feed application and scheduling of daily feeding. A nutritionally complete feed with relatively high protein content (40%) was used for the duration of the trial.

The tilapia chosen for this trial were obtained from a breeder who has been selectively breeding their fish since 1988. The breeding program is centered around a strain of the Genetically Improved Farmed Tilapia (GIFT). The supplier data suggested that it would take approximately 150 days to produce a 720 g fish.

A nursery system was stocked with 1.24 g fingerlings. After 42 days in the nursery system, 2,869 fish with a mean individual weight of 31.2 g were transferred to a single 32.5 m3 grow-out tank capable of supporting a final density in excess of 60 kg/m3. Throughout the trial a robotic feeder was programed to feed the fish once every hour. Feed was adjusted weekly based off of calculated growth rates. Throughout the trial only minor interruptions in the feeding schedule occurred during periods of maintenance or during sampling events.

After a total of 130 days fish reached an individual harvest weight of 720 g.  Final density was 61.8 kg/m3 with an overall FCR of 1.2:1. Survival rate was 97.1%.

The improved growth performance was attributed to the regularity of the feeding regime. This suggests improved genetics in Nile tilapia along with an improved feeding schedule would reduce time required to reach market size. An additional production trial is currently underway to lend further repeatability to these results.