Influences of metabolic traits on subclinical endometritis at different intervals postpartum in high milking cows.

Seventy pluriparous high-yielding cows were used to investigate the impact of metabolic traits and body condition score (BCS) during early lactation on subclinical endometritis diagnosed at weeks 5, 6 and 7 postpartum (pp). Blood samples were collected from animals with no peripartum problems from the second (W2) to seventh (W7) weeks pp to estimate some blood metabolites including non-esterified fatty acids (NEFA), ß-hydroxybutyric acid (BHBA), blood glucose, total cholesterol (T-chol) and blood urea nitrogen (BUN). Reproductive tract examination was carried out at weeks 5, 6 and 7 pp by endometrial cytology (percentage of polymorphonuclear cells; PMN%). Based on PMN%, animals having <5% were defined as subclinical endometritis group (ENDM group) while animals unaffected by endometritis were defined as no subclinical endometritis group (NOENDM group). Animals with endometritis during week 5 were identified as ENDM5, during week 6 identified as ENDM6 and during week 7 identified as ENDM7 or animals with no endometritis during weeks 5 (NOENDM5), 6 (NOENDM6) and 7 (NOENDM7) pp. Animals diagnosed at week 5; BUN and BCS were lower p < 0.05 in ENDM 5 than NOENDM5 group at W2, W4, W6 and W7. Cows diagnosed at week 6; T-chol was significantly higher (p = 0.05) in ENDM6 group (279.2 ± 12.5 mg/dl) than NOENDM6 group (246 ± 9.5 mg/dl) at W7. Moreover, blood glucose was significantly low (p < 0.05) in ENDM6 group when compared to NOENDM group at W4 pp (49.2 ± 1.8 vs 53.8 ± 1.3 mg/dl). BCS was significantly lower (p < 0.001) in animals suffered from endometritis during week 7 when compared to NOENDM7 cows at W3, W4, W5, W6 and W7. In conclusion, lower blood glucose, BUN and BCS could be a risk factor for cytologically diagnosed endometritis at weeks 5, 6 and 7 pp.

Association between evaluation of the reproductive tract by various diagnostic tests and restoration of ovarian cyclicity in high-producing dairy cows.

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 >or=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) during Week 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%) during Week 5 postpartum (P<0.05). The PMN% (4.5+/-6.5%) and VMCD (0.5+/-0.5) scores during Week 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.