Chicken coccidiosis costs the poultry industry over GBP 10 billion per year. The main method of preventing and controlling coccidiosis in chickens continues to be the use of drugs. Unfortunately, the prevalence of drug resistance in the field reduces or even eliminates the effectiveness of drugs, and drug residues in the food supply chain can also can be harmful to humans. Therefore, safe and effective anticoccidial drugs are urgently needed. Natural products have many advantages such as being safe, effective and inexpensive and are a sustainable way to control coccidiosis. In this study, the anticoccidial effects of six natural compounds were tested by Eimeria tenella infection. Oocyst production, cecum lesion, body weight gain, feed conversion ratio, and intestinal microbiota were measured. The results showed that nerolidol had a moderate effect on maintaining both body weight gain and feed conversion ratio. Silymarin and dihydroartemisinin showed significant anticoccidial effects by reducing total oocyst output. Dihydroartemisinin also significantly reduced the cecum lesion caused by Eimeria infection, but this compound may be toxic to the host at such informed doses because it decreases growth and survival rates. In addition, both silymarin and dihydroartemisinin partly restored the microbiota after challenge. This indicates that silymarin, dihydroartemisinin, and nerolidol are effective in the control of chicken coccidiosis. Our data provide basic knowledge about the anticoccidial effects of such natural compounds/derivates.
Keywords: Eimeria; anticoccidials; microbiota; natural products; silymarin.