EXTRATO DE UVA NA ALIMENTAÇÃO DE CODORNAS JAPONESAS EM FINAL DE CICLO SUBMETIDAS AO ESTRESSE POR CALOR

Abstract

The objective was to evaluate the use of grape extract in the diet of Japanese quails at the end of the production cycle, subjected to heat stress, aiming at improvements in production performance, egg quality, physiological parameters, digestibility, as well as hepatic and intestinal functions. The experiment was conducted in a completely randomized design, with five treatments (0, 250, 500, 750, and 1000 mg/kg of grape extract), six replicates, and six birds per experimental unit, totaling 180 quails. Zootechnical performance, fresh and stored egg quality, behavior, thermal comfort, physiological parameters, blood biochemical profile, biometry and bone mineralization, nutrient digestibility, gastrointestinal and hepatic tract morphometry, ovarian follicle count, and hepatic biochemical indicators (GOT, GPT, cholesterol, triglycerides, and total proteins) were analyzed. Grape extract did not significantly affect (p < 0.05) the productive performance, behavior, or physiological variables of quails, but it positively influenced (p < 0.05) aspects of egg quality (Haugh unit, albumen pH, and yolk color), in addition to raising body temperature effect on thermoregulation and crude protein digestibility. Although it did not promote consistent improvements in overall performance, the data point to the antioxidant and functional potential of grape extract, supporting its use as a natural additive in diets for laying hens subjected to heat stress. Grape extract, although it does not mitigate the effects of heat stress on the performance, metabolism, welfare, and intestinal and hepatic health of Japanese quails at the end of the production cycle, improves egg quality at doses of 250 to 400 mg/kg and has thermogenic potential, suggesting further investigation in young birds or under thermal comfort conditions.