Authors:
Kenneth Rono
,Andrew Tarus
,Julius O. Manyala
, Elizabeth Obado
, Charles Ngugi
, Hillary Egna And
Kevin Fitzsimmons ,Kenya |
Abstract:
Aquaculture intensification is characterized by high stocking density and need of high quality
and quantity of artificial feed. Increased fish biomass and feed input brings about rapid
deterioration of water quality hence a water quality management system need to be put in place
in such systems. Biofloc technology has been developed as a viable option to recycle nutrient by
maintaining a high carbon/nitrogen (C/N) ratio in the water in order to stimulate heterotrophic
bacterial growth which converts ammonia into useful microbial biomass. This study investigated
the effect of carbon source supplement in biofloc system on growth performance, water quality
and microbial community in the system. The experimental research was conducted at the
University of Eldoret from June - September 2017. A complete randomized design was used in
triplicate treatments. The supplementation carbon source constituted molasses, wheat flour,
potatoes flour and control respectively. At molasses carbon added treatments Nile tilapia
indicated the highest significant growth at (p < 0.05) than other treatments with final mean
weights (8.774±0.394g) and total length (7.956±0.123cm). The least growth of Nile tilapia
fingerlings was at control treatments with final mean (3.784±0215g, 5.827±0.114cm) weights
and length respectively. Molasses added bioflocexhibited highest protozoan (520.13±1.02),
rotifers (200.6±1.08), cyanobacteria (143.1±1.22) and diatoms (60.033±0.083) and improved
water quality as compared to other treatments. The results revealed that molasses added in
biofloc system improves Nile tilapia growth, microorganism colonization and water quality in
the system than other carbon added treatment tested. The study recommends molasses carbon
source for Nile tilapia fingerlings growth as it pertaining to the improved results of
microorganism levels and water quality obtained in the system. |
