Abstract

Eurycoma longifolia roots have been widely used for treating reproductive issues in humans and rat models, showing notable effects on male reproductive health. However, its impact on Japanese quails remains underexplored. This study aimed to investigate the effects of various concentrations of Eurycoma longifolia on reproductive performance and hormonal changes in two Japanese quail varieties.
A total of 240 females and 120 males of Brown- and White-feathered quails (120 females and 60 males per variety) were used. Birds were randomly allotted to four treatment groups with three replicates each (30 females and 15 males per replicate). They received water containing Eurycoma longifolia root extract (ELRE) at 0 mg/L (control), 125 mg/L, 250 mg/L, or 500 mg/L.
In males of both varieties, ELRE supplementation led to a dose-dependent increase in relative testes weight, testosterone levels, and total antioxidants. Meanwhile, cholesterol, triglycerides, HDL, and LDL levels decreased without affecting total protein. In females, ELRE did not affect ovary or oviduct weights or serum total protein but caused significant reductions in estrogen levels, especially in White quails. Interestingly, cholesterol and lipid profiles increased at higher doses (250 and 500 mg/L).
ELRE significantly advanced the onset of egg laying, increased hen-day egg production (HDEP%) during the first two weeks, and improved fertility, hatchability, and chick weights, particularly in Brown quails. These enhancements were associated with increased egg weight and egg mass.
In conclusion, water supplementation with 250–500 mg/L ELRE for Brown quails or 125 mg/L for White quails enhances the reproductive traits.

Key words: Eurycoma longifolia, fertility, hatchability, sex hormones, Japanese quail