Effect of Chitosan Nanoparticles Loaded Oxytetracycline Hydrochloride on Health Status of Common Carp (Cyprinuscarpio L.) Infected with Columnaris Disease

Abstract This study was aimed to evaluate the effect of chitosan nanoparticles loaded oxytetracycline hydrochloride on health status, and survival rate of common carp infected with Columnaris disease. A total 160 fish of Cyprinuscarpio L. weighed between 48-50g were randomly distributed into eight treatments, and 48 fish were used to determine LD50. (Two replications for each treatment). The bacterial concentration of F. column are that used for infection test after a serial dilution was 0.2ml (1.8 × 106 CFU/ml), then removal a few of scales near the caudal fin and injection subcutaneously. The trial injected fish treated by ordinary oxytetracycline hydrochloride as T0 in dose 20 mg/L and T1, T2, T3, T4 and T5 treated by chitosan nanoparticles loaded oxytetracycline hydrochloride in dose 20, 15, 10, 5, 2.5 mg/L respectively. The control (+) infected without gave treatment, whilst, control-was no infected. All the treatments gave the bath treatment 1-hour per-day for 7 days, clinical signs post treatment were evaluated also, RBC counts, WBC counts, PCV, Hb, Total proteins, Albumin, Globulin, A/G ratio and survival rate were measured. One week after the end of the treatment period, an improvement in health and feed consumption was observed in T4 and T3. The results revealed significant increases (P < 0.05) in PCV, Hb, RBCs count and WBCcount of C. carpio post-treatment in treated groups T4 (26.46%, 8.95 g/dl and 2.27 cell×106/mm3 and22.10 cell×103/mm3respectively) compared with control (+) (15.95%, 5.94 g/dl,1.55 cell×106/mm3 and19.13 cell×103/mm3respectively). In addition, Total proteins, Albumin, Globulin showed significant increase (P < 0.05) in T2, T3, T4, T5 comparison with the control+ group and highest values were recorded in T4. While, The result of A/G ratio revealed a significantly decreased (P 0.05) in all treatments in compared with Control(-) and no significant difference (P 0.05) compared with Control(+). The best A/G ratio recorded in T4 and T5. In addition, survival rate 90% recorded as the highest value in T4. This current administration technique of oxytetracycline, proved to become much more efficient with respect to conventional exposure and has the potential to minimize the usage of antibiotics in fish farms and regarding environmental effects.