EFFECT OF BIOTRONIC TOP LIQUID ON GROWTH PERFORMANCE AND DISEASE RESISTANCE IN NILE TILAPIA (Oreochromis niloticus)
An 84-day feeding trial was conducted to determine the effects of Biotronic® Top liquid on growth performance and disease resistance on Nile Tilapia (Oreochromis niloticus). The trial was conducted using 18 tanks, of 100 L water volume with aeration. Each tank was initially stocked with 45 male Nile tilapia with the average weight of 16.17±0.40g (mean±SE,). Biotronic liquid (BIOMIN Holding GmbH) is composed of three organic acids (formic acid, propionic acids and acetic acids and the BIOMIN Permeabilizing Complex. Three replications were used for six treatments of commercial diets supplemented at varying level of Biotronic Top Liquid i.e. 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 L of Biotronic® Top liquid per ton of feed. At the end of the feeding trial, immunological, biochemical and biometrical parameters were assessed. From the 56th day of feeding and onwards, the fish were immersed with 1 x 108 CFU concentration of Aeromonas hydrophila. The initial feeding rate was 4% of the total body weight, which was fed dividing into three meals daily. Part I of the experiment was to investigate the growth performance and feed utilization efficiency of Nile tilapia and Part II, was to analyze disease resistance during the challenge test when exposed to 1 x 108 CFU Aeromonas hydrophila.
Cumulative survival of tilapia decreased with the increasing dose of Biotronic® Top liquid (Fig. 1). Similarly, highest dose i.e. 2.5 L/ton (T6) showed 38.4% of higher (P<0.05) weight gain and significantly lower FCR value as compared to that of control (T1). Total bacteria counts also showed a significant decrease (P<0.05) after immersion compared to control treatment. Blood sample analysis also showed significant difference (P<0.05) with control. Therefore, present experiment suggests that the highest dose of Biotronic Top Liquid i.e. 2.5L/ton tested is the best in terms of growth rate, feed conversion rate and survival. However, more research can be done to evaluate the effects of higher dosages, bearing in mind the economics within a commercial aquaculture system.