@article{article_1652139, title={Juniper Tar Liquid Extract in Whole Milk: Effect on Oxidative Stress, Immune Response, Gut Flora and Renal Health in Holstein Calves}, journal={Journal of Animal Production}, volume={66}, pages={52–64}, year={2025}, DOI={10.29185/hayuretim.1652139}, author={Özkaya, Serkan and Erbaş, Sabri and Kara, Kanber and Arın, Evren}, keywords={Holstein calves, juniper, liquid extract, oxidative stress, immune response, gut flora}, abstract={Objective: Calves frequently suffer from digestive and respiratory diseases during the suckling period, leading to developmental issues, mortality, and economic losses. This study aimed to evaluate the effects of Juniper liquid extract (JLE) supplementation in whole milk on the health and growth performance of suckling Holstein calves. Material and Methods: Sixteen newborn Holstein calves were randomly assigned to 4 treatment groups (n=4 per group): Control (G1): Whole milk (WM)+ Calf starter (CS); G2: 1.25% JLE+WM+CS; G3: 2.5%JLE+WM+CS; G4: 5% JLE+WM+CS. Calves were monitored for digestive and respiratory diseases, gut microbiota, renal health, oxidative stress and immune response parameters. Results: Juniper tar liquid extract supplementation significantly reduced digestive and respiratory disease incidence. It suppressed the growth of gut pathogenic bacteria at weaning without affecting lactic acid bacteria. No adverse effects were observed on renal functions. JLE decreased oxidative stress levels, while antioxidant defence enzyme activity showed a non-significant increase. Immunoglobulin A, G, and M levels significantly increased, with the best results observed in the 1.25% JLE group. Conclusion: JLE, a by-product, can be safely used in calf nutrition to improve health by reducing disease incidence, modulating gut flora, and enhancing immune response. The 1.25% JLE supplementation provided the most effective results. Keywords: Holstein calves, juniper, liquid extract, oxidative stress, immune response, gut flora}, number={1}, publisher={Ege Zootekni Derneği}, organization={Isparta University of Applied Sciences Scientific Research Proejcts Coordination Unit}