PERIFITON LIVE FEED TO SUBSTITUTE PREDIGESTED ENZIM IN BRACKISHWATER TILAPIA NURSERY

Ibnu Sahidhir*, Lina Mutiara Sinaga, Azwar Thaib, Syafrizal, Muslim
 
Brackishwater Aquaculture Development Center of
Ujung Batee, Aceh, Indonesia
*ibnusahidhir@yahoo.com

 

An effective way to reduce ammonia and provide live feed is developing periphyton contained photosynthetic and heterotrophic organisms. High diversity of the periphyton community could provide complete and qualified nutrition for tilapia fingerlings. The study aimed to test bromelain, a predigested enzymes delivered to feed before feeding, at several levels of dosage in periphyton system. The test was conducted by 5 treatments and 3 replications. Bromelain was delivered to feed by top dressing, i.e. 0 ppm, 100 ppm, 200 ppm, 300 ppm, 400 ppm (w/w). To promote growing of periphyton community a cylinder-formed small mesh size hapa with dimension 60 cm in diameter and 90 cm high was used as each unit of replication. A unit of hapa contained 45 tilapia fingerlings sized +0,5 gr then ratio of weight/periphyton substrate was 0,5 gr/4 dm2. The tilapia was reared in brackishwater condition (10-12 ppt) and fed 4% of body weight/day with feeding frequency twice a day. The result showed that dosage range of bromelain 100-400 ppm was not significantly influenced specific growth rate (6,78-7,08%), feed conversion ratio (0,37-0,4) and survival rate (92-97%) (p>0,05) (Table 1.). In all treatment FCR decreased everyweek significantly (Figure 1). Here, It is concluded that predigested enzymes are not recquired for tilapia cultured in periphyton system