Screening of the anticoccidial effects of herb extracts against Eimeria tenella

Ionophorous antibiotics have been popularly used in the treatment of avian coccidiosis. Tissue residue of these antibiotics may be found in poultry, w e have sought safe alternative anticoccidial herbal materials for the contr ol of avian coccidiosis. Efficacy of extracts from 15 different herbs, incl uding Bupleurum chinese DC, Sophora flavescens Aiton, and Artemisia annua L inne was tested against Eimeria tenella. One-day-old broiler chicks were in fected with a USDA reference book of E. tenella, and administered various h erbal extracts. Survival rates, lesion scores, body weight gains, bloody diarrhea, and oocy sts excretions were investigated at the first and the second week after inf ection. Bloody diarrhea in the S. flavescens and Sinomenium acutum treated groups was milder than that of the other infected groups. Survival rates in the groups treated with Ulmus macrocarpa (100%), Pulsatilla koreana, Toril is japonica, Artemisia asiatica and S. flavescens (90%) were higher than th at of the infected control group (70%). Lesion scores in the groups treated with U. macrocarpa (1.40 +/- 1.14) or Pulsatilla koreana (1.60 +/- 1.82) w ere significantly lower than those of the infected control group (3.00 +/- 1.10). During the first week after infection, the weight gains in the group s treated with Quisqualis indica (232.9 +/- 43.5 g), S. flavescens (214.4 = /- 46.1 g) and S. acutum (211.3 +/- 29.4 g) were significantly higher than the infected control group (172.4 =/- 17.6 g). In conclusion, the data of the survival rates, bloody diarrhea symptoms, le sion scores, body weight gains and oocyst excretions indicate that the extr act of S. flavescens was the most effective. P. koreana, S. acutum, U. macr ocarpa and Q. indica were also effective. Further research on the above her bal materials will be carried out by the authors by chemical analysis of th e extracts. (C) 2001 Published by Elsevier Science B.V.