Effect of Substituting Polyether Ionophore Anticoccidial Drugs With 1, 8-Cineole for the Control of Eimeria Infections in Broilers

Abstract

Background: Coccidiosis is an important parasitic disease of broiler chickens. Drug resistance to the polyether polyether Ionophore anticoccidial drugs (PACDs) caused by long-term use has emerged as a significant problem in commercial broiler chicken production.

Objectives: This study explored the feasibility of 1,8-cineole (CIN) in replacing PACD with broiler feeding experiments and intestinal microecological experiments.

Methods: This experiment selected 21-day-old Lingnan yellow (LNY) broilers and randomly divided them into 8 groups, with 30 chickens in each group. They were uniformly fed with full feed during the breeding period. The experimental groups were as follows: (i) three broiler groups that were fed a PACD supplementation (G1: Salinomycin Premix [SAP] 60 mg/kg; G2: Monensin Premix [MOP] 100 mg/kg and G3: Maduramicin Premix [MAP] 5 mg/kg), (ii) three broiler groups that were administered different CIN dosages (G4: CIN-L 100 mg/kg, G5: CIN-M 150 mg/kg and G6: CIN-H 250 mg/kg) and (iii) two control broiler groups (G7: infected control group and G8: healthy control group). On the 23rd day, all groups were infected with coccidian cysts, except the G8 group which was used as a blank control. After 2 weeks of continuous feeding, the growth performance changes of broilers were analysed, and the intestinal lesions of eight groups of broilers were analysed after slaughter.

Results: Compared with PACD treatment, the average daily feed intake (ADFI) of the three CIN-treated groups increased by 13%, whereas the feed conversion ratio (FCR) reduced by 28%. FCR value for the high-dose CIN treatment was 2.04, 34% decline which compared with control group infected with spore oocysts. The anticoccidial index (ACI) of all PACD treatments was less than 120, whereas the ACI of the middle- and high-dose CIN treatments was higher than 180. In comparison to the Eimeria-infected control group, the diversity and total number of the microbiota in the CIN treatments increased significantly. Moreover, CIN treatment favoured the proliferation of intestinal probiotics, especially Lactobacillus sp.

Conclusions: CIN could have an inhibitory effect on parasite development as suggested in the gene function annotation of the intestinal microbiota. These results demonstrate that CIN may be a feasible natural alternative to anticoccidiosis drugs. So it was important to take precautions against and control coccidiosis in poultry production which has a lesser risk of creating resistance to substitutive PACDs.

Keywords: 1,8‐cineole; anticoccidial activity; broilers; intestinal microbial flora.

FIGURE 1

Blood stools in faeces of broilers infected with coccidian after 108 h (a) and cecum lesions of broilers infected with coccidian after 120 h (b). G1–G8 represent G1 group to G8 group, respectively. The yellow arrows point to the bloody stools, and red arrows point to the lesion.

FIGURE 2

The Shannon value, Chao value and PCoA of microbial flora in duodenum (a), small intestine (b) and cecum (c) of broilers.

FIGURE 3

Dominant genera in the intestines of broilers in the duodenum (a), small intestine (b) and cecum (c and d) of broilers.

FIGURE 4

The predicted KEGG function in microbial flora of duodenum (a), small intestine (b) and cecum (c).