No abstract

The effect of ovarian predominating structures and uterine condition on the result of some diagnostic tools for the evaluation of endometritis was studied in postpartum (pp) Holstein-Friesian dairy cows (n = 58). Endometrial cytology (EC) and the evaluation of vaginal mucus by vaginoscopy or Metricheck were performed weekly from week 3 to 7 pp. The ovarian studies involved the predominating structures including cystic follicles with plasma progesterone (P(4) ; more or <1 ng/ml; >23 mm), corpus luteum (CL), pre-ovulatory follicles (10-23 mm) and small follicles (<10 mm). The uterine conditions comprised uterine involution, tonicity and fluid in uterus (FIU) regarding echogenicity extent. During week 5, the percentage of polymorphonuclear neutrophils (PMN%) was higher (p < 0.05) in animals with pre-ovulatory follicles (mean ± SEM, 26.3 ± 7.6%) than animals having CL (11.0 ± 3.6%). In cystic ovaries, during week 5, PMN% was higher (p < 0.05) in follicular cysts with low progesterone (P(4) < 1 ng/ml; 9.3 ± 2.6%) than those with high P(4) (P(4) ≥ 1 ng/ml; 1.5 ± 1.1%). Moreover, PMN% was higher (p < 0.01) in animals with non-involuted uterus (11.5 ± 7.4%) than those with involuted uterus (2.7 ± 0.6%) during week 7 pp. The animals that had abnormal mucus determined by Metricheck was higher in animals with atonic uterus than those with tonic uterus during week 6 (82.6% vs 51.5%; p < 0.05) and 7 (71.4% vs 25.7%; p < 0.01) pp. In addition, by vaginoscopy, the prevalence of animals with abnormal discharge showing small follicles (100%, 5/5) during week 3 pp and pre-ovulatory follicles (40.0%, 8/20) during week 5 pp was higher (p < 0.05) when compared to those having CL during week 3 (33.3%; 1/3) and week 5 pp (7.7%; 2/26), respectively. In conclusion, endometrial cytology, Metricheck and vaginoscopy were influenced by the predominating various ovarian structures and uterine condition in early pp high-yielding dairy cows.

We conducted a field survey to estimate the relationship between embryo production and the body condition score (BCS) on a 5-point scale, as well as blood concentrations of insulin and glucose, in superovulated Holstein yearling heifers housed in a free-stall barn. They were provided total mixed rations to meet the nutrient requirements. The daily ration was divided between 2 feeding times, utilizing stanchions to separate heifers to avoid social status preventing inferior heifers from having enough feed. The recovered fluid after uterine flushing from heifers (n = 88, 13 mo old) was examined microscopically for the morphological grade and the development stage. The number of heifers in which BCS was 2.75, 3.00, 3.25, and 3.50 was 6, 35, 40, and 7, respectively. The 3.50 BCS heifers produced fewer excellent grade embryos than 3.00 or 3.25 BCS heifers significantly. The 3.50 BCS heifers produced significantly more morula than 2.75, 3.00, or 3.25 BCS heifers. In contrast, 2.75 BCS heifers produced more blastocysts than 3.25 or 3.50 BCS heifers. The 3.50 BCS heifers were hyperinsulinemic. Our results suggested no significant effect of BCS around 3.00 on embryo production, whereas 3.50 BCS heifers may have poorer embryo production.

ContentsClinically normal Holstein-Friesian cows (n = 43) were used to establish a relationship between the evaluations of the uterine condition by vaginoscopy, Metricheck, endometrial cytology (EC) and ultrasonography (US) during post-partum period (pp), and subsequent reproductive performance. The uterine status of the selected cows was evaluated by EC, Metricheck, US and vaginoscopy on a weekly basis from the third week (W3) to the seventh week (W7) pp. The animals were bred after a voluntary waiting period of 45-60 days pp and diagnosed for pregnancy status at 45 days after breeding by US. First service conception rate (FSCR) of bred animals was 32.6% (14 ⁄ 43). There was no significant difference in polymorphonuclear leucocyte percentage between conceived and non-conceived cows during different weeks post-partum. First service conception rate in animals with normal vaginal discharge as detected by Metricheck was significantly low when compared to those of abnormal discharge during W3 (2.3% vs 30.3%; p < 0.001) and W4 (4.7% vs 29.7%; p < 0.01) post-partum. Using US, the number of pregnant cows having fluid in uterus (FIU) during W6 (p < 0.01) and W7 (p < 0.001) post-partum was significantly lower (2 ⁄ 34, 4.7% and 1 ⁄ 43, 2.3%, respectively) than those that had no FIU (12 ⁄ 43, 27.9% and 13 ⁄ 43, 30.3%, respectively). Using vaginoscopy, FSCR in animals having abnormal discharge was significantly (p < 0.01) low when compared to that of normal discharge (2.4% vs 30.2%) during W5 and W6 postpartum. In conclusion, Metricheck during W3 and W4 and detection of FIU by US and vaginoscopy during W6 and W7 pp can be used as good predictive tools to anticipate the future reproductive performance of dairy cattle.

Background: Mastitis is a common infectious disease of the mammary gland and a major problem in the dairy industry. When cows affect mastitis, the number of somatic cells in their milk increases. It was reported that forebrain embryonic zinc finger-like (FEZL) encoding a stretch of 12 glycines (p.Gly105[12]) instead of 13 glycines (p.Gly105[13]) is associated with a lower somatic cell count, implicating the correlation between FEZL and mastitis resistance. Findings: To evaluate the impact of FEZL on mastitis incidence, a family with FEZL p.Gly105(12_13) polymorphism was generated via an embryo-transfer procedure. First embryos were recovered from cows inseminated with bulls homozygous for p.Gly105[12] and determined their sex. Based on transferring female embryos into recipient cows, 7 cows carrying the homozygous p.Gly105[12] and 5 cows carrying p.Gly105[12] and p.Gly105[13] were produced. These 12 cows with 15 cows of the same age and carrying the homozygous p.Gly105[13] were raised in the same station. After their deliveries via artificial insemination, milk yield and clinical mastitis were recorded during their first lactation period. Incidence of clinical mastitis was observed among cows carrying p.Gly105[12] significantly less than cows carrying the homozygous p.Gly105[13]. Moreover, affected cows carrying the homozygous p.Gly105[13] produced less milk with higher conductance than affected cows carrying p.Gly105[12], suggesting that cows carrying the homozygous p.Gly105[13] might suffer severer infection than cows carrying p.Gly105[12] because of their impaired immune response. Conclusions: The impact of FEZL on mastitis resistance was confirmed in a family with FEZL p.Gly105(12_13) polymorphism generated via an embryo-transfer procedure. Selection of cows carrying p.Gly105[12] could be beneficial in the dairy industry by reducing the incidence of mastitis.