Synbiotics as a Precision Nutrition Strategy to Improve Feed Efficiency and Environmental Sustainability in Ruminant Production Systems
Paulus C. Paat
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Dicky Pamungkas
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Dwi Yulistiani
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Wisri Puastuti
Research Center for Agroindustry, National Research and Innovation Agency, Indonesia.
Sindhu Akhadiarto
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Maman Surachman
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Yenni Yusriani
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Windu Negara
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Agustinus N. Kairupan *
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Derek J. Polakitan
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Procula R. Matitaputty
Research Center for Animal Husbandry, National Research and Innovation Agency, Indonesia.
Gabriel H. Joseph
Research Center for Agroindustry, National Research and Innovation Agency, Indonesia.
Jantje G. Kindangen
Research Center for Macroeconomics and Finance, National Research and Innovation Agency, Indonesia.
*Author to whom correspondence should be addressed.
Abstract
Feed efficiency is a key driver of both economic viability and environmental sustainability in ruminant systems, as feed constitutes the largest input cost and is closely linked to greenhouse gas (GHG) emissions. Synbiotics, synergistic combinations of probiotics and prebiotics, are emerging as innovative precision nutrition tools to modulate the rumen microbiome, enhance nutrient utilisation, and mitigate environmental impacts. This review synthesises recent advances in synbiotic use in ruminants, highlighting their mechanisms in improving fibre degradation, microbial protein synthesis, volatile fatty acid (VFA) production, and reducing enteric methane. The review adopts a focused and critical approach to identify relevant scientific contributions on the use of synbiotics in ruminant production, targeting the literature published from 2015 to 2025. Sources are mainly drawn from major scientific databases, including Scopus, Web of Science, and PubMed. By optimising these ruminal processes, synbiotics can substantially improve feed efficiency by increasing nutrient digestibility and reducing energy and nitrogen losses. Comparative insights between beef and dairy cattle are presented, along with key factors affecting efficacy such as microbial compatibility, substrate type, diet composition, and host physiology. The role of omics-based technologies in next-generation synbiotic development is also discussed. Despite promising outcomes, challenges remain in formulation stability, response variability, and cost. This review outlines strategic perspectives to support climate-smart, synbiotic-based interventions in ruminant nutrition.
Keywords: Synbiotics, rumen microbiota, feed efficiency, methane mitigation, sustainable livestock production