Asian Journal of Microbiology, Biotechnology & Environmental Sciences Paper

EFFICACY OF ECOFORCE AS A POTENTIAL SYNBIOTIC AGAINST THE UBIQUITOUS PATHOGEN, VIBRIO SPECIES IN THE PACIFIC WHITE LEG SHRIMP, LITOPENAEUS VANNAMEI CULTURE

EDWARD GNANA JOTHI GEORGE, GODFRED PONRAJ JEYARAJ AND VEERA RAVI ARUMUGHAM

Abstract

The study was conducted to evaluate the efficacy of the feed synbiotic Ecoforce on controlling the Vibrio infection, improving immunity and assimilation, thereby enhancing good growth, survival and FCR in the shrimp Litopenaeus vannamei. Also, the work emphasizes on the hematological changes in the infected and synbiotic used shrimps. The trial was conducted in three experimental ponds namely Pond A1, A2 and A3 and a control pond C1. Pond A1 comprised of Vibrio infected shrimps treated with Ecoforce on feed. Pond A2 contained of infested shrimps devoid of Ecoforce application. Pond A3 encompassed of normal shrimps administered with Ecoforce on feed. Control ponds on other hand involved shrimps with nil infection and no feed applications. Physico-chemical parameters were observed to stay balanced in all the study ponds except the concentration of dissolved oxygen. Dissolved oxygen concentration was significantly lower in the ponds with healthy shrimps (4.1 to 4.7±0.2 ppm) when compared to the infected shrimps (5.1 to 5.6±0.2 ppm). Surprisingly, Pond A1 with diseased shrimps when administered with 10gm/kg of Ecoforce in two meals for 5-7 days was observed to recover from Vibrio infection after treatment with significant variation (P<0.001) in recovery, mortality, feed intake, feeding time and weight gain. In stark contrast, Pond A2 with infected shrimps deprived of Ecoforce was recorded with mortality soaring up and noticed with feed drop and retarded growth on daily basis. Interestingly, pond A3 with typical shrimps upon Ecoforce application was observed to grow better than usual gaining a remarkable average body weight of 2.2±0.2 g in 9 days. Contrastingly, the control pond C1 logged a mediocre growth of 1.5±0.2 g in 9 days with noticeable mild antenna cut. As far as hematology is concerned, Total Hemocytes Count (THC) recorded an optimal level of 63±2.1 to 65±2.1 x 106 cells per ml in the synbiotic administered pond A3. Most interesting finding was infected shrimps with an average of 37±2.3 x 106 cells per ml exhibited THC of 61±2.1 × 106 cells per mL after 9 days of synbiotic treatment. Yet another interesting recording was on the clotting time of the hemolymph. Infected shrimps recorded an average clotting time of 123±2.4 seconds initially which upon administration reached a time of 48±2.4 seconds in 9 days of treatment. A closer look into the study reveals the fact that, the synbiotic composition of Ecoforce with potential probiotics and prebiotics improved the growth, and overall health status of the L. vannamei shrimps. Hence, the researcher culminates that the feed synbiotic Ecoforce is the quintessential combination towards developing sustainable and eco-friendly aquaculture.