Effect of Oxytetracycline on bacterial load of LABEOROHITA (Rohu) fish in culture pond

Abstract

The study was aimed to outline the anti biogram profiling of oxytetracycline against usual ecological
bacterial flora of culture ponds of L. ROHITA. After applying pelleted feeds treated with oxytetracycline (OTC)
at 2gm/kg the physicochemical parameters of water like temperature, pH, dissolved oxygen, alkalinity,
ammonia and nitrate were recorded weekly: 28.99 to 31.09°C, 7.58-7.95 ppm, 5.36-5.86 mg/L, 86.31-111.99
mg/L, 0.20-0.30 mg/L and 0.11-0.17 mg/L, respectively. The total viable counts of bacteria were found
4.9±1.03×103- 5.75±1.0×103cfu/mL in pond water, 5.62±1.0×107- 6.60±1.02×107cfu/g in sediments,
6.77±1.0×106-7.57±1.0×106cfu/g in gills, 6.02±1.02×107-8.32±1.0×107cfu/g in gut of L. ROHITA in control ponds.
After OTC treatment the total viable count of bacteria ranged from 3.1±1.19×103-3.1±1.20×103cfu/mL in
water, 3.1±1.13×106-4.27±1.10×106cfu/g in sediment, 2.82±1.25×105- 3.09±1.19×105cfu/g gill, 2.69±1.12×106
4.68±1.12×106cfu/g in guts of L. ROHITA respectively, indicating reduction of overall bacterial load below 1 log
in sediment, gills and guts of L. ROHITA significantly (P<0.005).