Influence of dietary oxytetracycline supplementation on growth, survival and immune status of cyprinus carpio

الملخص EN

A feeding experiment was carried out for 12 weeks to evaluate the effects of oxytetracycline (OTC) on growth performance and immunological parameters of Cyprinus carpio.

Eighty fish were assigned randomly to two dietary treatments.

The treatments were (I) a basal diet (control) (ii) basal diet + 100 mg OTC / kg feed.

Each dietary treatment had four replicate aquaria with 10 fish per aquaria.

Body weights gain, average daily weight gain, condition factor (K) and immunological parameters of fishes were determined biweekly during the feeding trail.

It was observed that at 4, 6, 8, 10 and 12 weeks fishes fed OTC medicated pellets had significantly (P < 0.05) heavier body weights than the control fishes.

Body weight gains, average daily weight gain and specific growth rate were also significantly (P < 0.05) improved by OTC diets throughout the experimental period.

Condition index (K) was significantly higher (P < 0.05) after 6, 8, 10 and 12 weeks of OTC administration.

The results indicated that oxytetracycline significantly suppressed IgM as well as the level of circulating white cells in Cyprinus carpio..

The survival after challenge was significantly affected by oxytetracycline in the present tests.

The present study suggests that, at concentrations commonly used in aquaculture, adding of OTC to feed enhanced growth of carp, but on the other hand suppress the immune response and decrease disease resistance.