Research Abstract
The uterine condition of clinically normal postpartum Holstein-Friesian dairy cows (n = 45) was evaluated once weekly (Weeks
3 to 7) by endometrial cytology, vaginal mucus collection device (VMCD), vaginoscopy, and ultrasonography to establish a
relationship with postpartum resumption of ovulatory cycles. The time of first detection of the corpus luteum (CL) by
ultrasonography and plasma progesterone concentration 1 ng/mL was recorded. By 49 d postpartum, 78% of the cows
(n = 35) had resumed ovarian function (CL group), whereas the remainder (n = 10) had no CL (NCL group). There was a positive
correlation between VMCD score and presence of fluid in the uterus in cows with a CL (P 0.01) duringWeek 3 postpartum but no
significant correlation in cows without a CL. Percentage of polymorphonuclear leukocytes (PMN%) was higher in the NCL group
(mean SEM, 24.6 9.4%) than in the CL group (11.7 2.2%) duringWeek 5 postpartum (P 0.05). The PMN% (4.5 6.5%)
and VMCD (0.5 0.5) scores duringWeek 5 in cows ovulating by Day 28 were lower (P 0.01) than the PMN% (15.0 14.3%)
and VMCD (1.1 0.9) scores in those ovulating by Day 49. In conclusion, higher PMN% at 5 wk postpartum was associated with
delayed resumption of ovarian cyclicity in high-producing dairy cows
Research Journal
Science Direct
Research Pages
pp 1153–1162
Research Rank
3
Research Vol
Vol. 72
Research Year
2009