UTTAR PRADESH JOURNAL OF ZOOLOGY

Poultry production depends heavily on soybean meal, fishmeal and cereal grains, and the search for alternative feed ingredients has intensified because of concerns about resource use, feed–food competition and price volatility. Most research on these ingredients has prioritised growth performance and nutrient digestibility, whereas their consequences for the quality of meat and eggs, which determine consumer acceptance and market value, have received less integrated attention. This critical narrative review evaluates how three groups of alternative ingredients, namely insect-derived meals, oils and live larvae; food by-products, including former food products, distillers dried grains with solubles and fruit and vegetable pomaces; and novel protein sources, including microalgae, single-cell proteins, duckweed and seaweed, affect the physicochemical, nutritional, sensory and safety attributes of poultry meat and eggs. Peer-reviewed literature was identified through structured searches of multidisciplinary and life-science indexes, supplemented by citation tracking and authoritative institutional sources, and was appraised for design, inclusion level, replication and outcome validity. The synthesis indicates that moderate inclusion of insect meals generally preserves carcass traits, meat colour stability, water-holding capacity and sensory acceptability, whereas the lipid fraction of black soldier fly larvae consistently shifts meat and yolk fatty acids towards greater saturation. Yolk pigmentation is the most reproducible egg response across insects, distillers grains, grape pomace and microalgae, but eggshell responses are contradictory. Polyphenol-rich by-products improve oxidative stability more reliably than they change composition, and microalgae provide the clearest route to omega-3 enrichment, at the cost of greater oxidative susceptibility and, at high inclusion, impaired performance. Confidence in these conclusions is limited by small replicate numbers, short feeding periods, poorly characterised ingredients, inconsistent reference diets and scarce evaluation of sensory quality, contaminant transfer and consumer response. Rearing substrate, processing method and inclusion level emerge as the main determinants of product quality, so ingredient standardisation is as important as further efficacy testing. Alternative ingredients can support poultry product quality, but their value depends on matching ingredient composition to explicit quality targets rather than on replacement of conventional proteins alone.