Relationship among seminal antigenicity, antioxidant status and metabolically active sperm from Holstein-Friesian (Bos taurus) bulls

Sperm antigenicity has been implicated as a regulatory factor for acquiring fertilizing competence in the female reproductive tract. Overt immune response against the sperm proteins leads to idiopathic infertility. Hence, the aim of the study was to evaluate the influence of the auto-antigenic potential of sperm on the antioxidant status, metabolic activities and reactive oxygen species (ROS) in bovine. Semen from Holstein-Friesian bulls (n = 15) was collected and classified into higher (HA, n = 8) and lower (LA, n = 7) antigenic groups based on micro-titer agglutination assay. The neat semen was subjected to the evaluation of bacterial load, leukocyte count, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and lipid peroxidation (LPO) levels. Antioxidant activities in seminal plasma and intracellular ROS levels in the post-thawed sperm were estimated. The number of leukocytes was lower (p p p p p r = 0.73, p p r=–0.66), CAT (r=–0.72), LPO (r=–0.602) and intracellular ROS (r=–0.835). The findings were represented in graphical abstract. It is inferred that the higher auto-antigenic levels protect the quality of bovine semen by promoting sperm metabolism and lowering ROS and LPO levels. Seminal antigenicity impacts semen quality. Increased antigenicity decreases peroxidase-positive leukocytes and post-thaw sperm ROS-positive cells, yielding reduced lipid peroxidation and a greater percentage of metabolically active sperm indicative of efficient antioxidant defense mechanisms exerting a protective influence during cryo-stress.