Figure 3.

Comparison of motion and morphological index. Two motion indices were evaluated for boar 2004, 2012, and 2023. (A) straightness (STR, %) was calculated as the ratio of straight-line velocity (VSL) to average path velocity (VAP), and (B) linearity (LIN, %) was defined as the ratio of VSL to curvilinear velocity (VCL). Morphological abnormality was evaluated by measuring (C) sperm head elongation ratio (%) and (D) area (μm²). Elongation was calculated by the ratio of minor to major axis of sperm head, and area corresponded to the head size. Semen was collected at five different times from the boars (n = 5). The collected semen was divided in triplicates and applied to CASA analysis. The results are expressed as mean±SD. p<0.05. CASA, computer assisted semen analysis; SD, standard deviation.