<b>Biphasic effects of </b><b><i>Callicarpa nudiflora</i></b><b> water extract on rumen fermentation </b><b><i>in vitro</i></b><b> and microbial communities in sheep</b>

This study investigated the effects of varying doses of Callicarpa nudiflora water extract (CW) on in vitro rumen fermentation and sheep microbial activity. Four rumen-cannulated hybrid sheep were selected to provide mixed rumen fluid, and the powder substrate remained consistent with the diet fed to the sheep. A total of 14 supplementation levels (0–25 g/kg fresh substrate) of CW were designed based on a completely randomized design, including 0, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 14, 16, 20 and 25 g/kg. Each treatment was replicated in duplicate across three independent batches, resulting in a total of six biological replicates per treatment. The flasks were incubated at 39°C for 24 hours in water with a rotation speed of 80 r/min.