Effect of Zinc Oxide and Selenium Nanoparticles on Milk Production Efficiency and Related Gene Expression in Egyptian Baladi Goats

This study assessed the impact of oral administration of zinc oxide (ZnO) and selenium (Se) nanoparticles on milk production and gene expression in Baladi goats. Twenty-two pregnant females, 30 days before parturition, were divided into five groups: Group 1 (n=4) served as control; Groups 2 and 3 (n=4 each) received 150 mg ZnO and 0.3 mg of Se in microparticle (MP) forms, respectively; Groups 4 and 5 (n=5 each) received 15 mg ZnO and 0.03 mg Se in nanoparticle (NP) forms, respectively. Milk yield, composition, and gene expression related to milk production were analyzed. Results indicated a significant increase (P<0.001) in dry matter intake in the ZnO-NPs and Se-NPs groups, with an improved feed conversion ratio. Daily and overall milk yield, as well as fat-corrected milk yield, were highest in the NPs groups, particularly ZnO-NPs. Milk composition remained unchanged. Gene expression analysis showed significant upregulation of POU1F1, IGF-1, PPAR gamma, CSN2, and FASN in the NPs groups compared to the MPs and control groups, with the highest expression levels observed in the Se-NPs group. These findings suggest that ZnO-NPs and Se-NPs enhance milk production efficiency and upregulate key genes involved in milk yield in Baladi goats.