Relative accuracy of the identification of ovarian structures in the cow by ultrasonography and palpation per rectum

Manual palpation or ultrasonographic examination of the cow's genital tract are currently used by veterinarians involved in reproductive management, b ut knowledge of the potential and the limitations of both methods is import ant to obtain an optimal accuracy in the diagnosis of physiological and pat hological ovarian structures. This review presents the main features of man ual and ultrasonographic characteristics of follicles, corpora lutea (with or without a cavity), follicular and lutenized cysts and the reliability of the two methods is compared. Manual diagnosis of follicles <10 mm is rathe r inaccurate, but ultrasound offers the possibility to diagnose follicles < 5 mm and to measure their inner diameter: The predictive values of the pres ence or absence of a corpus luteum as determined by palpation are similar ( 78 vs. 75%). Manual or ultrasonographic diagnosis of the growing or regress ing corpus luteum is rather difficult. The positive predictive value of a m ature corpus luteum diagnosed by ultrasonography is lower (87%) than the ne gative predictive value (92%). Compared to manual palpation, ultrasonograph y permits a better estimation of the number and to determine more precisely the size of the mature corpus luteum. The positive values for follicular c ysts diagnosed by palpation or by ultrasonography are 66 and 74% respective ly, and for luteal cysts, the values are 66 and 85%, respectively. Manual palpation or ultrasonography are useful tools to diagnose ovarian st ructures in the cow. The accuracy of such methods can be enhanced by securi ng information on the reproductive history of the animal, palpation of uter ine horns, vaginal examination or progesterone determinations. (C) 2000 Har court Publishers Ltd.