Abstract
Background:
Prebiotics contribute substantially to livestock physiology by promoting health equilibrium. Chicory leaves have been a subject of research as a natural prebiotic and exhibit various phytoconstituents that act as nutraceutical agents. However, the in vivo efficacy of ethanolic leaf extract remains under-researched.

Aim:
This study aimed to examine the impact of ethanolic chicory leaf extract (CLE) on the blood profile, intestinal microbial species, and histology of male rabbits.

Methods:
To prepare the leaf extract, ethanol was used as the solvent and was extracted using a rotatory evaporator. Forty-eight rabbits were divided into 4 groups (12/group). G0 was kept as the control, while the other groups G1, G2, G3 were given doses of 1, 2, and 3 mL/kg BW of CLE, respectively, on a daily basis for 45 days. On 15th, 30th, and, 45th day samples (n=4 per group) were collected to assess hematological parameters via complete blood count, E. coli and Lactobacillus colonies through plate count agar, and intestinal tissue histology by microtomy.

Results:
One-way ANOVA indicated a dose-dependent impact of CLE on the research parameters as the greatest improvements were observed in the highest-dose group (G3), followed by the medium- (G2) and low (G1) dose groups compared to control group. There was improvement in all blood parameters (p≤0.05), whereas there was a reduction of E. coli and increment of Lactobacillus population (p≤0.05) in the ileum and cecum. Histological examination showed an increase in villus length and crypt depth, along with a decrease in villus width (p˂0.05).

Conclusion:
Administration of CLE to rabbits acts as a microbiota-modulatory agent that boosts gut health and structure while maintaining the blood profile. Hence, it can be used as a natural tonic for livestock to promote bio-functionalities and can be a potential alternative to synthetic prebiotics.

Key words: Chicory leaf extract; E. coli; Hematological indices; Histology; Lactobacillus.