ISSUE FOCUS FEED & ADDITIVE MAGAZINE February 2026 67 ism-wide adaptive responses • Selective microbiota modulation enhancing beneficial host-microbe interactions • Improving resilience without immune system costs • Metabolic optimization supporting growth and feed efficiency In this context, “metabolic optimization” refers to the enhancement of metabolic processes within livestock or poultry to support efficient growth, feed conversion, and physiological resilience, without relying on immune-mediated pathways that are energetically costly. Scientific evidence shows that metabolic optimization involves improving nutrient assimilation, promoting more efficient energy production in tissues (such as mitochondrial ATP synthesis), and minimizing wasteful metabolic byproducts, resulting in reduced feed intake per unit of growth and better utilization of dietary nutrients (Rauw 2025, El-Hack 2025). FUNCTION OF FEED ADDITIVES AND FEED COMPONENTS Feed additives and feed components in many ways represent the complete other side of the spectrum from antibiotics, but are there some features where antibiotics and feed additives come close in their functions? There is a good case to be made for certain feed additives ultimately working in the animal to achieve similar benefits to the desirable, non-medicinal usage of AGPs. Especially with the emergent model of AGP mechanism described above, it is worth discussing how certain feed additives can support the same end goal: promoting animal resilience. Lillejhoj et al (2018), Gutierrez-Chavez et al. (2025) and others outline the end-results such products must achieve: • Growth performance & feed conversion efficiency • Promotion of animal productivity under real-world conditions • Support gut homeostasis • Non-adverse effect on the immune system • Reduction of oxidative stress • Support organism in mitigation of enteric inflammatory consequences Within the hormetic model, possibly the most important systemic benefit is, in one phrase, promoting resilience. Phytomolecules have long been used, in human and animal medicine, for the same end goal. The mechanisms described below should naturally be seen with caution, as phytomolecule microbiome effects can be subtler and context-dependent. However, the substantiating literature has been increasingly accumulating on these specific topics. AGPs microbiota intestinal tract other distant cells epithelial host cell regulation of bacteria fitness microbiota modulation productive efficiency increase tolerance to diseases influence animal fitness response: growth cellular tolerance trigger mitochondria stress response adaptive response and virulence mechanisms Figure 2. From Fernandez Miyakawa et al., 2024. Photo: Freepik.com
RkJQdWJsaXNoZXIy MTUxNjkxNQ==