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

Md. Abul Kashem¹, Md. Naim Uddin², Mohammad Mosarof Hossain¹, Md. Tawheed Hasan¹, Syed  Ariful Haque³, Mohammed Nurul Absar Khan⁴, Mohammed Masud Hassan⁵ and Ferdaus Mohd. Altaf Hossain⁶

¹Faculty of Fisheries, Sylhet Agricultural University,

² Dept. of Fisheries Technology, Bangladesh Agricultural University

³Dept. of Fisheries Technology, Sheikh Fajilatunnesa Mujib Fisheries College

⁴Faculty of Fisheries, Chittagong Veterinary and Animal Sciences University,

⁵Noakhali Integrated Agro Industries Ltd. Noakhali Sadar, Noakhali, Banglladesh.

⁶Faculty of Veterinary & Animal Science, Sylhet Agricultural University, Bangladesh.

*Corresponding Author’s Email: ferdaus.dps@sau.ac.bd

Accepted 03 March, 2014

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).

Keyword: Bacterial load, culture ponds, L. rohita, oxytetracycline.