KURUBA MANOHAR 01 01 Broiler production relies on highquality protein sources to support rapid growth efficient feed utilisation and optimal carcass yield Soybean meal and fish meal have long dominated commercial diets due to their balanced amino acid profiles and digestibility however rising global demand fluctuating prices landuse limitations and environmental concerns have accelerated the search for sustainable alternatives This review synthesizes verified research on insect meals fermented plant proteins leaf meals singlecell proteins and agroindustrial byproducts as emerging protein replacements in broiler nutrition Black Soldier Fly Larvae meal Tenebrio molitor meal fermented soybean meal Spirulina Chlorella and bacterial protein meals have demonstrated the ability to maintain or improve growth performance feed conversion ratio nutrient digestibility gut morphology and meat quality in controlled feeding trials Mechanistic insights reveal improvements in villus height crypt depth enzymatic activity antioxidant markers and immune function Sustainability assessments highlight reduced greenhouse gas emissions lower water and land demands and valorization of organic waste streams Despite these advantages constraints include antinutritional factors chitin content variable nutrient profiles processing costs regulatory barriers and consumer acceptance issues This comprehensive review consolidates multidisciplinary evidence to guide the strategic inclusion of alternative proteins in broiler diets and identifies future research priorities for scaling these ingredients into commercial poultry systems Copyright (c) Journal of Science Engineering Technology and Management Science. All rights reserved 2026