Assessment of induced luteolysis in Buffaloes: Functional, structural, and hemodynamic dynamics

Abstract

This study investigated the temporal dynamics of PGF₂α-induced luteolysis in buffaloes using color Doppler ultrasonography, luteal morphometry, and hemodynamic parameters. Eight multiparous, cyclic buffaloes received 500 µg Cloprostenol intramuscularly, and changes in luteal blood flow, structural regression, and vascular parameters were assessed over 72 hours. A significant decline in luteal color pixel intensity was observed from 2996.71±375.66 at 0 h to 117.43±30.62 at 72 h, indicating progressive luteal vascular regression. Concurrently, corpus luteum (CL) diameter, area, and volume decreased significantly (p<0.01), with regression rates averaging 1.33 mm/day. Doppler indices showed rising resistance (RI: 0.72 to 0.95) and pulsatility indices (PI: 1.20 to 2.07), coupled with declining blood flow volume (BFV: 5772.33 to 5012.22), reflecting reduced perfusion. A mean follicular growth rate of 0.72 mm/day post-luteolysis was recorded, highlighting the luteal-follicular transition. These findings validate the application of Doppler ultrasonography as a non-invasive tool to monitor functional and structural luteolysis, optimize estrus synchronization protocols, and enhance reproductive management in buffaloes.