Effects of early pregnancy diagnosis by per rectal palpation of the amniotic sac on pregnancy loss in dairy cattle

Abstract

To determine effects of per rectal amniotic sac palpation (ASP) for pregnancy diagnosis during early gestation on pregnancy loss in lactating cows. Controlled, randomized block design. 368 pregnant dairy cows. Pregnancy was detected via transrectal ultrasonography (TRUS) at day 29 (day of estrus = day 0), and cows were allocated into a control group (n = 167 cows) and ASP group (180). Control cows were not subjected to pregnancy diagnosis via palpation per rectum. Per rectal ASP was performed between days 34 and 43 by only 1 experienced veterinarian. All cows were reevaluated with TRUS on days 45, 60, and 90. 21 cows were removed because of illness. Pregnancy loss between days 29 and 90 occurred in 44 of 347 (12.7%) cows. Pregnancy loss for the control and ASP groups from days 29 to 90 occurred in 22 of 167 (13.2%) and 22 of 180 (12.2%) cows, respectively. Late embryonic pregnancy loss (days 29 to 45) for the control and ASP groups occurred in 18 (10.8%) and 15 (8.3%) cows, respectively. Early fetal pregnancy loss (days 46 to 60) for the control and ASP groups occurred in 2 of 149 (1.3%) and 6 of 165 (3.6%) cows, respectively, and late fetal pregnancy loss (days 61 to 90) for the same groups occurred in 2 of 147 (1.4%) and 1 of 159 (0.6%) cows, respectively. Pregnancy diagnosis via per rectal ASP during early gestation did not increase pregnancy loss in dairy cattle.