To study the anticoccidial effect of Piper sarmentosum extracts (PSE) in experimental broiler coccidiosis, 270 one-day-old Wenchang broiler chickens were randomly assigned to six groups, each with three replicates (n = 15). The six groups were blank control group (BC), negative control group (NC), positive control group (PC), and another three PSE addition groups. Chickens in three control groups were fed a basal diet without PSE supplementation. Chickens in the three PSE addition groups were fed a basal diet supplemented with PSE at 100 (T100), 200 (T200), and 300 (T300) mg/kg of feed, respectively. At 15 days of age, chickens in group NC, PC, and three PSE addition groups were challenged with an oral dose of 1 × 10(5) Eimeria tenella oocysts each chick. Chickens in group PC were fed with diclazuril solution in water for 5 days after 48 h with oocysts inoculation. The results showed that PSE and diclazuril improved growth performance and significantly (P < 0.05) decreased oocysts per gram in inoculated broiler chickens. PSE and diclazuril significantly (P < 0.05) decreased nitric oxide at 6 and 9 days post-inoculation relative to the NC group, respectively. At 6 and 9 days post-inoculation, PSE supplementation at 200 mg/kg in the diet increased concentration of interleukin 2 (IL-2) and interferon gamma (IFN-γ) (P < 0.05). PSE supplementation at 200 mg/kg in the diet significantly (P < 0.05) increased mRNA expressions of IFN-γ and IL-2 in the cecum of chickens at 9 days post-inoculation relative to the BC and NC group. The current results showed the anticoccidial properties, and beneficial effect on intestinal mucosa damage of PSE in broiler chickens that had been challenged by coccidiosis.
Keywords: Anticoccidial effect; Broiler chickens; Coccidiosis; Piper sarmentosum extracts.