Associations of periparturient plasma biochemical parameters, endometrial leukocyte esterase and myeloperoxidase, and bacterial detection with clinical and subclinical endometritis in postpartum dairy cows.

This study was aimed at demonstrating associations between peripheral biochemical parameters, endometrial leukocyte esterase (LE) and myeloperoxidase (MPO), and bacterial detection with the degree of endometrial inflammation, and determining the best time postpartum for diagnosing endometritis to predict subsequent fertility in dairy cows. Plasma albumin, blood urea nitrogen (BUN), total cholesterol (T-cho), NEFA, and BHBA concentrations were analyzed in 43 Holstein cows at 3, 5 and 7 weeks postpartum (W3, W5 and W7). Endometrial samples were collected at W3, W5 and W7 to examine LE and MPO activities, bacterial detection rates, and PMN% profiles. The 43 cows were divided into healthy (HE), subclinical endometritis (SE), and clinical endometritis (CE) groups, classified differently at W3, W5 and W7 based on the definitions of SE and CE for each of the three weeks pp. LE level had an association with PMN% in all weeks pp (P<0.05). Albumin and BUN levels had weak negative associations with endometrial PMN% at W3. Pathogenic bacterial detection rates were higher in the cows with endometritis at W3 and W5. Conception rate at first artificial insemination tended to be lower (P=0.057) in the cows diagnosed with endometritis at W3 than in the healthy cows. In conclusion, associations were found between endometrial LE and endometritis, but not for MPO and endometritis. Diagnosing endometritis in W3 may be the best moment to predict subsequent fertility.

Plasma anti-Müllerian hormone profile in heifers from birth through puberty and relationship with puberty onset.

The current study aimed to define the plasma profile of anti-Müllerian hormone (AMH) and follicle stimulating hormone (FSH) in heifers during postnatal life until achieving puberty, as defined by plasma progesterone (P4) profile, to demonstrate a relationship between AMH and age of puberty onset. Blood samples collected from 11 Japanese Black female calves within 1 week after birth (W 0) and then biweekly until the sixth week after puberty (WP 6) were assayed for AMH, FSH, and P4. The heifers were classified into two groups based on age of puberty onset: ≤42 weeks (early puberty group; EP, n = 4) and ≥44 weeks (late puberty group; LP, n = 7). Minimal plasma AMH concentration occurring at W 0 gradually increased to its peak level by W 10 (fourfold higher than W 0; P < 0.01) before gradually declining to a steady plateau 6 weeks before puberty (WP -6). The AMH peak was preceded by a significant rise in plasma FSH at W 4, W 6, and W 8 compared with W 0. Plasma AMH at W 16 positively correlated with WP 4 and WP 6 (r = 0.69 and 0.71, respectively; P < 0.05). Overall plasma AMH and FSH was significantly higher and lower in EP compared with LP, respectively. In conclusion, heifers exhibit a characteristic plasma AMH profile during postnatal life, such that plasma AMH at an early prepubertal age could be a biomarker for precocious puberty and postpubertal AMH levels.