Dietary Cold Pressed Watercress and Coconut Oil Mixture Enhances Growth Performance, Intestinal Microbiota, Antioxidant Status, and Immunity of Growing Rabbits

SIMPLE SUMMARY: This study focused on using watercress oil and/or coconut oil as growth promotors in intensive rabbit production to promote growth and development while guarding the body against pathogens. From the perspectives of both health and economics, the results showed that several benefits including improvement in growth, feed utilization, antioxidant status, and immunity, and reduction in pathogenic cecal bacteria could be gained by adding 1 g coconut oil + 1 g watercress oil or 0.5 g coconut oil + 1.5 g watercress oil/kg to the diets of rabbits. ABSTRACT: The present study assessed the effect of dietary supplementation with coconut oil (CNO), watercress oil (WCO), and their mixture as promoters of growth, antioxidant status, immunity, and intestinal microbiota in growing rabbits. A total of 120 rabbits were distributed into six groups (20 rabbits/group) receiving a basal diet without supplementation (G1) or diet supplemented with 2 g CNO (G2), 2 g WCO (G3), 0.5 g CNO plus 1.5 g WCO (G4), 1 g CNO plus 1 g WCO (G5), or 1.5 g CNO plus 0.5 g WCO/kg (G6). Live body weight and feed conversion ratio were significantly higher in the G4 and G5 groups than in the other groups. Superoxide dismutase activity and reduced glutathione concentration were significantly improved in the CNO or WCO diets. Supplemental CNO plus WCO at all tested levels produced the best lysozyme and complement 3 activities. Cecal lactobacilli, coliform, Enterobacteriaceae, and Clostridium spp. populations were lower in the group who received the 1 g CNO + 1 g WCO/kg diet than that in the control group. Dietary supplementation of 1 g CNO + 1 g WCO or 0.5 g CNO + 1.5 g WCO/kg had the potential to improve growth, feed utilization, antioxidant status, and immunity, and reduce cecal pathogenic bacteria in rabbits.