Bu çal›flmada, levrek bal›klar›nda (Dicentrarchus labrax L.) görülen Lernanthropus kroyeri (van Beneden, 1851) enfestasyonlar›n›n tedavisinde kullan›lan emamektin benzoat›n etkisinin de¤erledirilmesi amac›yla farkl› dozlar uygulanan befl grup oluflturuldu. Emamektin benzoat bu gruplara 7 gün süreyle yem içinde 0 (kontrol), 10, 25, 50 and 100 µg kg-1 dozlar›nda verildi. Denemenin yap›ld›¤› suyun s›cakl›¤› 16-16,5 °C olarak tespit edildi. Emamektin benzoate ile yap›lan tedavinin L. kroyeri’nin larva ve eriflkin evrelerine karfl› etkili oldu¤u bulundu. Tedavinin uyguland›¤› süre içinde 10, 25, 50 and 100 µg kg-1 dozlar›nda ilaç verilen gruplarda parazit say›s›, s›ras›yla % 55, 50, 43 and 74 azal›rken, ayn› süre içinde control grubunda parazit say›s›n›n % 8 artt›¤› belirlendi. Denenen bütün dozlarda, emamektin benzoate ile yap›lan tedavi nedeniyle gruplar aras›nda büyüme ve ölüm oran› bak›m›ndan fark bulunmad› (P > 0,05).

Five different dose groups were formed to evaluate the efficacy of emamectin benzoate as a treatment for Lernanthropus kroyeri (van Beneden, 1851) infestation in cultured sea bass Dicentrarchus labrax (L.). Emamectin benzoate was administered in-feed at doses of 0 (control), 10, 25, 50, and 100 µg kg-1 biomass day-1 for 7 consecutive days. Parasites were counted on days 7, 14, and 21, and comparisons were made to untreated control fish. Seawater temperature was 16-16.5 °C. Treatment with emamectin benzoate was effective against larval and mature stages of L. kroyeri. The number of L. kroyeri in the control fish increased by 8% during the 21 days of the study, whereas their number decreased in the treated fish by 55%, 50%, 43%, and 74% at the dose of 10, 25, 50, and 100 µg kg-1, respectively. No differences were observed with respect to growth between the treatment groups and the control group, and no mortality was observed at the end of the study.