Effect of LED light colour and stocking density on some hematological and oxidative stress parameters in Japanese quailsDereli Fidan, Evrim (Avtor) Koc Yildirim, Ece (Avtor) Japanese quailsLED lightheterophile/lymphocyte ratiooxidative stressstocking densityThe study evaluated the effects of light-emitting diode (LED) light colour and stocking density on the hematological parameters, oxidative metabolism, and organ weights of quails. Several key management factors that influence the welfare of broilers include light color and stocking density. For this reason, this study aimed to reveal the effect of different light colors and stocking densities on the hematological and oxidative stress parameters in Japanese quails. For this purpose, levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) were measured in quails subjected to different light colors and stocking densities, using commercially available ELISA kits. In this study, 720 1-day-old mixed-sex Japanese quails (Coturnix coturnix japonica) were randomly assigned to one of six treatments, each having four duplicates of 30 birds. The experiment was designed as a 3 x 2 factorial arrangement of treatments, with three LED light colours (white, blue, and green) and two stocking densities (low = 200 cm2/bird and high = 100 cm2/bird). At 42 days of age, 20 quails from each treatment group were randomly selected for some hematological parameter analysis. According to the results obtained, the heterophile/lymphocyte (H/L) ratio was significantly higher in the white LED light colour treatments. However, the effects of stocking density on the H/L ratio were not significant. The oxidative stress indicator MDA was unaffected by the light colour, however, the high stocking density drastically reduced liver CAT and GSH activities. The heart weight was lower in the quail subjected to blue LED light. The heart and liver organ weights were not affected by stocking density. In conclusion, whereas white LED light increases the H/L ratio and the stress situation, it does not affect the oxidative stress indicators. These findings highlighted the need to identify optimum LED light colours for quails in commercial production settings in order to increase flock welfare. More research is needed to understand the effects and find the best colour of LED light for quails at varied stocking densities.20262026-08-10 11:09:36Članek v reviji185567UDK: 628.979: 612.11:577.1:636.59ISSN pri članku: 2385-8761DOI: 10.26873/ SVR-2058-2025COBISS_ID: 285046019sl