RESUMEN
Aims: Two in vivo experiments were carried out to investigate the effects of saponins on rumen fermentation, plasma metabolites, nutrients digestibility, and performance in small ruminant. Study Design: In the experiment 1, three Baluchi sheep (48± 4.3 kg, body weight) were randomly assigned to three experimental diets in a 3×3 Latin square design to determine the effects of saponins on digestibility, ruminal fermentation characteristics and plasma metabolites. Saponins were added at levels of 0, 100 and 200 mg/kg dry matter intake to diet. In the experiment 2, eighteen Saanen kids (6–7-month) were used in a completely randomized design to determine the effects of saponins on ruminal fermentation, plasma metabolites, and body measurements. Saponins were added at levels of 0, 36 and 54 mg/kg dry matter intake. Place and Duration of Study: The trials were conducted at the Research Farm of Agriculture Faculty of Ferdowsi University of Mashhad (Iran), between February 2011 and October 2011.