Effects of Fermented Grape Seed in Breeding-Pigeon Diets on Growth Performance, Immune Responses, and Oxidative Status of Offspring Squabs

Abstract

Simple Summary Fermented grape seed (FGS) is produced from grape-processing by-products and contains a variety of nutrients and bioactive compounds, indicating its potential value as a feed ingredient. During early growth, squabs depend primarily on parental feeding; therefore, the composition of the parental diet may influence their growth and physiological status through parental nutrient transfer. In the present study, FGS was added to breeding-pigeon diets to evaluate its effects on growth performance, carcass traits, meat quality, immune responses, and redox status in squabs. The results suggest that dietary supplementation with 30 kg FGS per 1000 kg of diet may exceed an appropriate inclusion level, as evidenced by increases in inflammation-related indices, lipid peroxidation markers, and several serum metabolic parameters. FGS20 showed numerical advantages in several production traits but also increased breast muscle press loss and did not improve hepatic redox status. Therefore, none of the tested supplementation levels can be considered optimal or recommended, and the range of 10–20 kg FGS per 1000 kg of diet requires further validation. These findings provide information to guide the rational use of grape-processing by-products in meat pigeon diets.