Bioefficacy of dietary inclusion of <i>Nannochloropsis oculata</i> on <i>Eimeria</i> spp. challenged chicks: clinical approaches, meat quality, and molecular docking

Abstract

Although anticoccidial drugs have been used to treat avian coccidiosis for nearly a century, resistance, bird harm, and food residues have caused health concerns. Thus, <i>Nannochloropsis oculata</i> was investigated as a possible coccidiosis treatment for broilers. A total of 150 1-day-old male Cobb broiler chicks were treated as follows: G1-Ng: fed a basal diet; G2-Ps: challenged with <i>Eimeria</i> spp. oocysts and fed basal diet; G3-Clo: challenged and fed basal diet with clopidol; G4-NOa: challenged and fed 0.1% <i>N. oculata</i> in diet, and G5-NOb: challenged and fed 0.2% <i>N. oculata</i>. Compared to G2-Ps, <i>N. oculata</i> in the diet significantly (<i>P</i> < 0.05) decreased dropping scores, lesion scores, and oocyst shedding. Without affecting breast meat colour metrics, <i>N. oculata</i> improved meat quality characters. At 28 days of age, birds received 0.2% <i>N. oculata</i> had significantly (<i>P</i> < 0.05) higher serum levels of MDA, T-SOD, HDL, and LDL cholesterol compared to G2-Ps. Serum AST, ALT, and urea levels were all decreased when <i>N. oculata</i> (0.2%) was used as opposed to G2-Ps. Histopathological alterations and the number of developmental and degenerative stages of <i>Eimeria</i> spp. in the intestinal epithelium were dramatically reduced by 0.2% <i>N. oculata</i> compared to G2-Ps. Molecular docking revealed a higher binding affinity of <i>N. oculata</i> for <i>E. tenella</i> aldolase, EtAMA1, and EtMIC3, which hindered glucose metabolism, host cell adhesion, and invasion of <i>Eimeria</i>. Finally, <i>N. oculata</i> (0.2%) can be used in broiler diets to mitigate the deleterious effects of coccidiosis.