Evaluation of the Metricheck device and the gloved hand for the diagnosis of clinical endometritis in dairy cows

The objective of this study was to compare 2 surrogate vaginal examination methods (i.e., gloved hand and a vaginal device) with vaginoscopy as a reference method for diagnosing clinical endometritis in dairy cows. Holstein-Friesian cows (n = 1,002) in 2 commercial dairy herds in Germany were examined for endometritis at 21 to 27 d in milk (DIM) by using 1 of 3 vaginal diagnostic methods. Vaginal examinations were performed either with a speculum (reference method), a vaginal device (Metricheck, Simcro, New Zealand), or a gloved hand. Vaginal discharge adhering to the diagnostic tool was classified according to a vaginal discharge score ranging from 0 to 3 (where 0 = translucent mucus, 1 = mucus containing flecks of white or off-white pus, 2 = less than 50% white or off-white mucopurulent material, and 3 = greater than 50% white or yellow pus that may be sanguineous). Cows with vaginal discharge scores of 1 to 3 received 500 μg of cloprostenol after examination and again 14 d later (35 to 41 DIM). The prevalence of endometritis in both herds was 40.6 and 40.3%, respectively. With the Metricheck device, significantly more cows were diagnosed as affected with endometritis than by examination with a speculum or a gloved hand (47.5 vs. 36.9 and 36.8%). Binary logistic regression for the risk of conception after first AI as an outcome variable, with vaginal discharge score, diagnostic method, and farm as covariates, revealed a significant effect of degree of endometritis, but not of the diagnostic methods. Survival analyses for the hazard of insemination and pregnancy within 200 DIM, respectively, revealed a significant effect of degree of endometritis, herd, and parity, but not of the diagnostic tool. It can be concluded that any one of the 3 vaginal examination methods can be used interchangeably, without a negative effect on reproductive performance.