Reliability of ultrasonography for detecting the ovarian changes across the estrous cycle in buffaloes

Abstract

Ultrasonographic findings of the ovarian structures were compared with the macroscopic findings for assessing the reliability of sonographic observations in buffaloes. Buffalo genitalia (505) were studied and were transported to laboratory in ice. Ultrasonography of the ovaries was done using 7.5 MHz linear probe after immersing the genitalia in a water tub. The genitalia were examined visually and then dissected with a scalpel blade to assess the number and diameters of the ovarian structures. Approximately 80% buffalo genitalia belonged to luteal phase and only 13% to the follicular phase. Ultrasonography was highly reliable for estimating the number of follicles of &gt4 mm diameter (P&lt0.01; b=0.88, R2=86.5%; r=0.93; sensitivity=92.8%) as well as for detecting mature corpora lutea (sensitivity, 90%; positive predictive value, 96%). However, the results of ultrasonography were not encouraging for studying follicles of 14 mm diameter (P&gt0.10; b, 0.71, R2, 59.3%; r, 0.77) and corpora lutea of young and regressing stage (sensitivity&lt71%, positive predictive value &lt63%).