Effects of Saponins on Rumen Fermentation, Nutrients Digestibility, Performance, and Plasma Metabolites in Sheep and Goat Kids

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.
Methodology: Ammonia-N concentration was determined using the distillation method and blood metabolites were determined by an automated biochemical analyzer using commercial kits.
Results: In the experiment 1, saponins administration had no effect on apparent nutrient digestibility, ruminal pH, ruminal ammonia-N concentrations. Results showed that sheep receiving saponins had lower (P<0.05) plasma cholesterol concentrations than the control. In addition, saponins administration decreased plasma cholesterol concentrations, but did not affect the concentration of blood urea nitrogen, glucose, and triglycerides. In the experiment 2, saponins administration had no effect on DMI, ruminal pH, ammonia-N concentrations, body measurements and plasma metabolites except cholesterol. In goat kids we observed significant reduction in plasma cholesterol concentrations.
Conclusion: Administration of saponins in the diets of small ruminants did not improve nutrient digestibility, ruminal fermentation and growth performance, but reduced blood cholesterol concentration.