The anticoccidial activity of the fluoroquinolone lomefloxacin against experimental Eimeria tenella infection in broiler chickens.

Abstract

Coccidiosis is a crucial parasitic disease of the poultry industry. As a result of the enormous global economic losses and the increased resistance to the conventional anticoccidial agents, there is a continuous need to find new anticoccidials. Here, the anticoccidial effect of the fluoroquinolone lomefloxacin versus diclazuril in experimentally infected broilers was tested for the treatment of Eimeria tenella infection. Ninety 14-day-old Cobb strain broiler chickens were allocated into five groups, each with 18 chicks. Group 1 (G1) was separated as an uninfected negative control and received no treatment; group 2 (G2), infected untreated (positive control); group 3 (G3), infected and treated with lomefloxacin at a dose rate of 100ppm in drinking water; group 4 (G4), infected and treated with diclazuril at a dose rate of 2.5ppm in drinking water; group 5 (G5), infected and treated with lomefloxacin at a dose rate of 100ppm plus diclazuril at dose rate of 2.5ppm in drinking water. Clinical signs, mortality rates, number of oocysts per gram of faeces (OPG), growth performance parameters (weight gain: WG and feed conversion ratio: FCR), lesion scoring, haematological and serum biochemical analyses, antioxidant biomarkers and histopathologic inspection of the caeca were used as evaluation criteria for the anticoccidial efficacy of both lomefloxacin and diclazuril. The findings herein showed that administration of lomefloxacin and/or diclazuril improved growth performance parameters (WG, FCR) and significantly (P ≤ 0.05) reduced OPG, and diminished the severity of bloody diarrhoea and mortalities. Additionally, haematological indices and serum biochemical parameters such as ALT, AST, ALP, creatinine, uric acid, total proteins, albumin and globulin were improved. Finally, a significant elevation in the levels of the antioxidant biomarkers was observed in the chicks of G3, G4 and G5 as compared with those of G2.