Transrectal Doppler sonography of uterine blood flow during the first 12 weeks after parturition in healthy dairy cows

Evaluation of endometrial vascular flow index and echogenicity following experimental induction of subclinical endometritis in dairy cows

This study was conducted aiming to investigate impacts of experimentally induced endometritis on the vascular perfusion and echogenicity of the endometrium in dairy cows. Following estrus synchronization and applying cytological and bacteriological examinations, Holstein cows (n = 9) were enrolled in the experiment. The endometrial blood flow and echogenicity in the middle of each uterine horn were evaluated two times a week until the subsequent estrus by power Doppler and two dimensional ultrasonography. On days 3 and 4 of the subsequent estrous cycle, 15 milliliters of a suspension containing pure culture of Truperella pyogenes (8-15 × 108 cfu/mL) were inoculated into the body of uterus, and then endometrial blood flow and echogenicity were evaluated according to the applied procedure of the previous cycle. The provided results indicated different vascular perfusion and echogenicity among various days of normal estrous cycle, while after induction of endometritis, no significant difference observed. Comparing vascular perfusion between the normal and infectious estrous cycles also revealed significant difference in days 3, 10 and day 14 of two cycles. The differences of endometrial echogenicity between days 3 and 10 of normal and infectious estrous cycle were also significant. In conclusion, inducing endometritis significantly altered pattern of vascular perfusion and echogenicity of uterine horn during certain days of the estrous cycle.

Ultrasonographic Screening of Dairy Cows with Normal Uterine Involution or Developing Postpartum Uterine Disease Using B-Mode, Color, and Spectral Doppler

Uterine involution, ovarian activity, and incidence of postpartum uterine disease (PUD) were assessed in forty-eight dairy cows from calving until the 10th postpartum week. Postpartum follow-up included evaluation of uterine involution and ovarian structures by B-mode, Doppler color, and Doppler spectral ultrasound of the right uterine artery in cows with no calving or postpartum uterine problems (healthy cows). Data from cows that developed PUD (PUD cows) were compared with healthy cows matched by herd and days in milk (DIM). Data were analyzed by descriptive statistics, simple regression, one-way ANOVA, or repeated ANOVA measures, and in data analysis of healthy cows, uterine horn diameter assessed by B-mode ultrasound ranged from 22.9 ± 2.4 to 19.4 ± 1.4 mm and 19.9 ± 2.2 to 20.5 ± 2.3 mm from the fourth to the seventh postpartum week in the left and right uterine horns, respectively (P > 0.05). During the study, 15 and 7 cows had corpus luteum in the left and right ovaries, respectively. The mean time for the first postpartum CL was 30.1 ± 3.2 DIM (min 8, max 67 DIM). In data analysis of PUD cows, uterine blood flow assessed by color Doppler ranged from 7.4 ± 4.0 to 43.75 ± 10.3% in cows that developed PUD compared to 16.7 ± 11.0% in healthy cows (P > 0.05). No statistically significant changes were found in resistance index, pulsatility index, time-averaged maximum velocity, time-averaged mean velocity, or diastole/systole ratio (D/S) in cows that developed PUD compared to healthy cows (P > 0.05). Finally, no correlation was found between Doppler spectral parameters and uterine involution (P > 0.05). Our data suggest that cows receiving transition diets and exhibiting normal calving undergo a rapid macroscopic uterine involution and ovarian follicular dynamics resumption. Complete ultrasound evaluation provides valuable data for assessing uterine involution in postpartum dairy cows.

Cow and management factors and their association with estimates of uterine size and position at the time of insemination of dairy cattle

This study examines factors affecting uterine size and position determined at 30-36 days postpartum in dairy cattle. The final study population consisted of 328 dairy cows, all calving during the warm season. Uterus position (pelvic, pelvic-abdominal, abdominal) and uterus size (small, medium, large) was measured by ultrasound on Day 30-36 postpartum. Multiparous cows had a larger uterus positioned in the abdominal cavity (p = .03) and a male newborn was associated with a larger uterus (p = .022). The number of cows with the uterus in the abdominal cavity was higher among multiparous and high producer (p < .0001) cows. High producers were 0.41 times more likely to have a small uterus in a pelvic position. The most important finding of this study was that the delivery of a male dairy, rather than beef, calf was related to the least optimal maternal uterus size and position.

Administration of Estradiol Benzoate Enhances Ovarian and Uterine Hemodynamics in Postpartum Dairy Buffaloes

The postpartum (PP) period is a crucial stage for the resumption of reproductive performance and ovarian cyclicity in dairy buffaloes. The present study aimed, for the first time, to assess the effect of the administration of estradiol benzoate (EB) on ovarian and uterine hemodynamics in PP dairy buffaloes. Eight pluriparous acyclic domestic buffaloes were enrolled in the present experiment and received a dose of 10 mg of estradiol benzoate (EB) intramuscularly 4 weeks after parturition. All animals were examined two times before EB administration (days -3, and -1) and on the day of EB administration (day 0), followed by examinations on days 1, 3, 5, 7, and 9 post-EB administration. The middle uterine artery (MUA) and ovarian artery (OA) blood flow patterns were assessed using a color Doppler ultrasound device. The reproductive parameters were (1) the cross-sectional diameters (cm) of the OA and MUA, (2) cranial uterine horn thickness (UHT; cm), and (3) hemodynamic changes within the MUA on both the ipsi- and contra-lateral sides of the previous pregnant horn and within the OA corresponding to the ovarian tissues. The examined blood flow parameters were the pulsatility index (PI), resistance index (RI), peak systolic/end-diastolic ratio (S/D), time-averaged maximum velocity (TAV; cm/s), uterine blood flow rate (BFR; bpm), and uterine blood flow volume (BFV; mL/min). Concomitantly, blood samples were collected from the coccygeal vein, and the sera were stored at -18 °C for use in estradiol (E2-17β) and nitric oxide (NO) assays. The results revealed increases in both OA and MUA cross-sectional diameter (cm) on the ipsi-lateral and contra-lateral (p < 0.05) sides within 24 h until day 9 post-treatment. The values of the RI and PI of blood flow within the OA and MUA on the ipsi-lateral and contra-lateral sides of the previous pregnancy were obviously lower (p < 0.05) at 24 h after the administration of EB, and then, started to gradually elevate, reaching the pre-treatment values on day 9 after EB administration. Both the BFR and BFV in the OA and MUA significantly increased from 24 h to 72 h after EB administration on both the ipsi-lateral and contra-lateral sides (p < 0.05); then, their values started to decrease to reach the pretreatment value on day 9 after EB administration. Both E2 and NO concentrations significantly increased (p < 0.05) from 24 h until day 3 after EB injection and then started to decline after that, reaching the pre-treatment value on day 9. In conclusion, the administration of EB enhances the ovarian and uterine blood flow concomitantly with increased levels of NO in PP dairy buffaloes.

The vaginal and uterine blood flow changes during the ovsynch program and its impact on the pregnancy rates in Holstein dairy cows

Aim

OvSynch is a hormonal protocol for synchronization of estrus and use of artificial insemination (AI) at an optimal time without adverse effects on the ovaries or uterus. This study investigated the use of noninvasive color Doppler ultrasound to assess changes in uterine and vaginal blood flow during the Ovsynch program for synchronization of estrus and its relation to the pregnancy rates in Holstein cows.

Materials and methods

The experimental cows received an intramuscular dose of 10 μg of a GnRH analogue (G1), followed 7 days later with an intramuscular injection of synthetic prostaglandin F2α (P: PGF2α) analogue (500 μg cloprostenol sodium), and given a 10 μg, injection of the GnRH analogue (G2) i.m. 48 h after the PGF2α treatment, and the cows were bred 14-16 h after. Uterine and vaginal perfusion were investigated by performing transrectal Doppler ultrasonography of both the uterine and vaginal arteries in Holstein cows at different time points during the Ovsynch program to determine: peak systolic velocity (PSV), time-averaged maximum velocity (TAMV), the volume of blood flow (BFV), pulsatility index (PI), resistance index (RI), resistance impedance (S/D) and diameters of uterine (UA) and vaginal (VA) arteries. Steroid hormones were also assayed. Transrectal ultrasonography (TUS) was performed at 32 and 60 days to confirm the pregnancy per artificial insemination (P/AI).

Results

The uterine PSV, TAMV, and PV were greater at the time of the cloprostenol sodium and second GnRH injections (p<0.05) than at the time of the first GnRH injection. The vaginal PSV, PV were greater at the time of the cloprostenol sodium than at the time of the first and second GnRH injections (p<0.05). The receiver operating characteristic curve (ROC curve) indicated a high correlation between the uterine and vaginal blood flow and the rate of the pregnancy (p<0.05). The area under the ROC curve was 0.920 and 0.87 (p<0.05) for vaginal and uterine arteries respectively at time of G2. The serum levels of progesterone, estrogen and cortisol were correlated with the P/AI (p<0.05). The P/AI significantly decreased from 43.9 % at 32 d to 35.37 % at 60 d.

Conclusion

These results indicate that noninvasive Doppler ultrasonography is a valid method to evaluate changes in the characteristics of uterine and vaginal blood flow in cows during the Ovsynch protocol. Furthermore, vaginal and uterine blood flow are two determinant factors for the higher conception rates in Holstein dairy cows.

Astragalus membranaceus Additive Improves Serum Biochemical Parameters and Reproductive Performance in Postpartum Dairy Cows

The purpose of the study was to assess the recovery, immune function, and breeding efficiency of postpartum dairy cows fed Astragalus membranaceus (AM) as a feed additive. The experiment used a completely randomized design. Cows were randomly assigned to two groups: (1) Control group fed total mixed ration (TMR; CON group, n = 15); (2) AM group fed TMR and AM (AM group, n = 15). The AM group was fed 675 g/day. The experimental results showed that compared with the CON group. The breeding interval of the AM group of dairy cows had a tendency to shorten (0.05 < p < 0.1). Plasma viscosity (PV), Plasma fibrinogen (FIB), the red cell aggregation index (TRCAI), Calcitonin (CT), Immunoglobulin M (IgM), and Luteinizing hormone (LH) results of AM group showed a time-treatment interaction (p < 0.05). Furthermore, the result of the study revealed that feeding AM as feed additives to dairy cows during the postpartum period had positive effects on wound recovery, immune function, endocrine regulation, and breeding efficiency.

Ovarian and uterine haemodynamics and their relation to steroid hormonal levels in postpartum Egyptian buffaloes

The current study aimed to assess the ovarian and uterine haemodynamics in postpartum (pp) Egyptian buffaloes and their relation to steroid hormonal levels (progesterone and estrogen). Six multiparous buffalos with normal calving were examined by using trans-rectal Doppler sonography to assess the blood flow in ipsilateral and contralateral ovarian and uterine arteries. Doppler parameters viz. peak systolic velocity (PSV), blood flow volume (BFV), resistance (RI) and pulsatility index (PI) were measured at 1st till 6th postpartum weeks. In addition, diameters (mm) of the ovarian and uterine arteries and the vascularisation area (mm2) of ovary were determined. The blood samples were collected starting from 1st week post calving and every week thereafter following each ultrasound Doppler examination for assay of progesterone and estradiol. Results indicated that PI and RI increased consistently and significantly (P<0.05) till the 6th week post calving as compared to those recorded at 1st week in ipsilateral ovarian and uterine arteries. However, the blood flow volume and peak systolic velocity in both ovarian and uterine arteries decreased gradually from 1st week till the 6th week after calving. There were very strong positive correlations between PSV and BFV, in both ipsilateral and contralateral ovarian and uterine arteries. Blood concentrations of progesterone were lower (P<0.05) during the first four weeks than those recorded at 5th and 6th postpartum weeks. This trend was reversed for blood estradiol 17-β. The results of the present investigation concluded that Doppler ultrasonography is a suitable tool for assessing changes in ovarian and uterine perfusion during the puerperium.

Cervical histomorphology of successfully detorted uterine torsion affected buffaloes subjected to intracervical hyaluronidase or PgE1 treatment

Twenty-four buffaloes presented between 36-72 h of occurrence of uterine torsion were successfully detorted and equally divided to intracervical hyaluronidase enzyme or prostaglandin E1 (PgE1) treatment or control group for investigating the treatment effectiveness for complete cervical dilatation. Intracervical treatment was administered immediately after detorsion, and cervical biopsy was collected immediately before instituting treatment and at time of cervical dilatation or at 18 h post detorsion in case of non-dilated cervix. The doppler indices of middle uterine artery were evaluated at an hour before detorsion and 0.5 h after detorsion. In control group, none of the buffaloes exhibited cervical dilatation, whereas, 87.5% buffaloes of hyaluronidase group and 62.5% of PgE1 group exhibited cervical dilatation. Following intracervical treatment, lamina propria showed loosely arranged collagen fibres along with hemorrhages, polymorphonuclear (PMN) cells and intercollagen space filled by homogenous/ watery substance in case of dilated cervix. In non-dilated cervix, the collagen fibres were tightly arranged with lesser number of PMN cells and negligible haemorrhages at 18 h after treatment. The doppler indices of the middle uterine artery revealed improvement (P<0.05) in blood supply towards cervix and uterus in buffaloes exhibiting complete cervical dilatation. In conclusion, intracervical hyaluronidase treatment in immediate post-detorsion period in uterine torsion affected buffaloes can be an effective strategy to ensure complete cervical dilatation and per-vaginal fetal delivery.

Incidence, clinical patterns, and risk factors of postpartum uterine diseases in dairy cows from high-altitude tropical herds

The cow's uterus sustains bacterial contamination and active inflammation after calving as part of the normal physiological process of uterine involution. Although the definition, incidence, and risk factors for postpartum uterine diseases (PUD) have been documented in annual calving systems with high-producing cows on total mixed ration, the literature contains little information for other production systems. The objective of this study was to quantify the incidence risk and factors associated with metritis, clinical endometritis, and cytological endometritis in high-altitude tropical dairy herds in a pasture-based system. A total of 248 cows from 5 commercial dairy herds in northern Antioquia, Colombia, were enrolled in this prospective observational longitudinal cohort study. Data collection and PUD diagnosis were performed at d 0, 3, 10, 17, 24, 31, 38, 45, and 52 (±1) after parturition. Between 60 and 70 d, cows were systematically enrolled in a synchronization protocol, and herds were visited monthly for pregnancy diagnosis until 180 ±15 d. The multivariable logistic regression model of variables associated with PUD occurrence included (a) parity, season of calving, transition diet, and body condition score at calving; (b) blood calcium, phosphorus, and magnesium concentrations, and milk urea nitrogen, β-hydroxybutyrate and fat-to-protein ratio; and (c) dystocia, retained placenta, and delayed uterine involution. The incidences of puerperal metritis, clinical metritis (MET), clinical endometritis (CE), and cytological endometritis (CYTO) were 2.8, 25, 29, and 26%, respectively. Retained placenta and dystocia were associated with MET, and MET was associated with CE. Low blood calcium concentration at calving was associated with CYTO. Overall, 51.2% of the cows suffered at least 1 category of PUD during the first 60 d postpartum (DPP). However, cows also suffered from different consecutive clinical events of PUD (MET, CE, and CYTO) during the follow-up period (0 to 180 ±15 DPP). These events could be grouped into 4 types (which were referred to as "clinical patterns") based on interactions between MET, CE, and CYTO.

Analyzing the correlation between uterine involution and blood flow in post-partum dairy cows

The objective of this study was to assess the applicability of trans-rectal color Doppler ultrasonography for quantification of uterine blood flow in 30 healthy lactating Jersey cows on a weekly interval from days 0 to 56 after parturition (day 0). Significantly higher time average mean velocity (TAMEAN), time average maximum velocity (TAMAX) and blood flow volume (BFV-TAMEAN and BFV-TAMAX) in artery ipsilateral to previous gravid uterine horn (PGUH) was found as compared to contralateral middle uterine artery (MUA) on day 0 to 14 postpartum. Similarly, transverse diameter (D) of ipsilateral MUA was significantly higher as compared to contralateral MUA during first two weeks after parturition. Clinical uterine involution completed on day 32.47±0.85 postpartum as demonstrated by B-mode ultrasonography and a significant correlation (r= 0.31–0.44 from day 7–28) between size of PGUH and BFV-TAMAX was found. Also, significant correlation between transverse diameter of ipsilateral (r=0.56–0.80) and contralateral (r=0.51–0.79) MUA-D and BFV-TAMAX was found on different examination days. In conclusion, trans-rectal Doppler ultrasonography was a useful tool to investigate haemodynamic changes whereas PI, RI, Doppler pulse duration and systolic upstroke time were found unsuitable to indagate alterations in uterine perfusion during post-partum period.

Evaluation of haemodynamic changes of uterine arteries using Doppler ultrasonography during different stages of pregnancy in Bos indicus cows

The objectives of the study were to evaluate haemodynamic changes and their relationships among ipsilateral (IPS) and contralateral (CONT) uterine arteries (UA) during different stages of pregnancy in Bos indicus cows. Multiparous pregnant cows (n = 40) having a gestation length 30.47 ± 0.54 (mean ± SD) days were randomly enrolled and subjected to Doppler ultrasonography sequentially at 1st, 2nd, 4th, 6th and 8th months of gestation. Blood flow indices including diameter of UA (mm), blood flow volume (BFVo, ml/min), blood flow velocity (BFVe, cm/s), time-averaged maximum velocity (TAMV, cm/s), pulsatility index (PI) and resistance index (RI) were recorded. Data were analysed with mixed models using the PROC MIXED procedures, and Pearson correlation coefficients were calculated using the PROC CORR statement in SAS. The final statistical models included the fixed effects of side of UA, gestation month and the interaction between side of UA and gestation month. Results revealed that the mean diameter of the UA (12.13 ± 0.22 vs. 10.09 ± 0.22), BFVo (1236.33 ± 0.55 vs. 770.41 ± 0.55), BFVe (17.18 ± 0.42 vs. 15.58 ± 0.42) and TAMV (17.11 ± 0.44 vs. 15.77 ± 0.44) was higher (p < .05) in IPS as compared to CONT side of the UA in cows. However, PI and RI did not differ between IPS and CON arteries of uterus in cows. A very high and positive correlation (r = .89; p < .05) existed between the diameter of UA and BFVo starting from 1st to 8th months of gestation in IPS as well as CONT sides of UA. Moreover, TAMV was highly and positively correlated (r = .91; p < .05) with BFVe throughout the gestation. In conclusion, these haemodynamic changes in the UA could be used as a valuable validity tool to differentiate the compromised pregnancy in Bos indicus cows.

Hemodynamic changes evaluated by Doppler ultrasonographic technology in the ovaries and uterus of dairy cattle after the puerperium

The present detailed study aimed to establish for the first time the ovarian and uterine hemodynamic change in dairy cows after the end of the puerperal period to investigate a possible association between Doppler indices and volume of blood flow. Twenty cows weighing 500-600 kg (mean 400 ± 50 kg) and 4-5 years of age (mean 3.2 ± 0.5 years) categorized into two main groups (true anestrum, with corpus luteum, n = 10) and (normal cyclic, n = 10), The period of examination started from day 39 till day 70 after calving with day after day routinely examination by b-mode and Doppler performed on both ovaries with ovarian arteries (OA) and uterus with uterine arteries (MUA) in the ipsilateral (ipsi) and contralateral (contra) side to ovulation, in addition to a thickness in horns and body was measured. Estradiol and progesterone were also measured. Results showed that both Doppler indices in the OA and MUA ipsi and contra had a positive (P ≤ 0.001) correlation with contra Doppler indices, but revealed a negative (P ≤ 0.05) correlation with ipsi and contra Doppler velocities, blood flow rate and volume in anestrum cows. Both ovarian and uterine ipsi indices showed an increase (P ≤ 0.05) in the anestrum cows, and both PSV and EDV of both arteries ipsilateral showed (P ≤ 0.05) a decrease in the anestrum cows, the ipsi and contra ovarian and uterine colored % were lower in anestrum group than the normal group. Estradiol (P ≤ 0.05) decreased in anestrum cows than the normal, while progesterone increased in the anestrum group. Conclusion, although uterine and ovarian morphology were changed in anestrum cows, the vascular system of the ovary as well as uterus underwent much more marked vascular changes, the most significant being that of blood flow velocities and volume.

Doppler indices of middle uterine artery as a tool for predicting the fetal status in cattle with uterine torsion and the recovery of uterine blood flow subsequent to detorsion

The aim was assessment of blood flow to uterus in cattle suffering from uterine torsion as a tool for predicting the fetal survivability after detorsion. Dairy cattle (14) with uterine torsion were detorted and fetal delivery was completed within 30 min after detorsion. Doppler sonography of middle uterine artery ipsilateral (IpsiUA) and contralateral (ContUA) to the side of torsion was carried out before uterine detorsion and 30 min after fetal delivery for Doppler indices, viz. blood flow volume (BFV), time-averaged peak velocity (TAP), resistance index (RI) and pulsatility index (PI). Before uterine detorsion, RI-IpsiUA and PI-IpsiUA were high in comparison to their values in ContUA. Although RI-IpsiUA and PI-IpsiUA had difference between their values before uterine detorsion and 30 min after fetal delivery, but in contrast, at the same time point, there was no difference in RI-ContUA and PIContUA. In comparison to RI-IpsiUA and PI-IpsiUA before detorsion, their respective values decreased after fetal delivery subsequent to successful detorsion, and were almost similar to their respective post-fetal delivery RIContUA and PI-ContUA. In cases where fetus after detorsion of uterus was delivered dead, in the middle uterine artery ipsilateral to the side of uterine torsion, BFV-IpsiUA and TAP-IpsiUA were low, whereas PI-IpsiUA were high. In conclusion, depicting the blood flow within middle uterine artery using Doppler sonography could be helpful in predicting the viability of fetus in uterine torsion affected cattle and may confirm the resumption of blood flow to uterus subsequent to detorsion.

Hemodynamics of the uterine and umbilical arteries during the perinatal period in ewes

Examining feto-maternal blood flow is extremely important for accurate prenatal control and predicting adverse conditions during puerperium. We aimed to analyze blood flow of uterine artery (UA) and umbilical artery (UMA) from and subsequent to mid-gestation, lambing and postpartum of 15 ewes, subjected to lambing induction with aglepristone. Hemodynamic variables, diameter and blood flow of UA and UMA were determined by Doppler and B-mode ultrasonography at 60, 90 and 120 days of pregnancy, at 12 h before, 12 h after first aglepristone injection and 12 h after induction and days 1, 3, 5, 7, 15 and 30 after lambing. The UMA peak systolic:diastolic velocity (S/D), resistance index (RI) and pulsatility index (PI) decreased from mid-pregnancy until 120 d, whereas peak systolic velocity (PSV), end diastolic velocity (EDV) and time average maximum velocity (TAMAX) increased towards 120 d. The UMA RI additionally decreased at 12 h after lambing induction. The UMA diameter and volume increased from mid-gestation until 12 h before lambing induction. UA PSV and TAMAX increased from 60 until 90 days of pregnancy, while EDV, PSV and TAMAX decreased soon after parturition, with a further reduction at 7 days. The UA diameter and volume decreased during postpartum, stabilizing by 15 days after parturition. In conclusion, pregnancy is marked by progressive increase in uterine and umbilical blood flow, while lambing acutely diminishes umbilical vascular resistance, suggesting lack of progesterone influence on vasodilation. Conversely, puerperium is characterized by reduction in uterine blood supply mostly within the first 2 weeks of postpartum in sheep.

Scopolamine for uterine involution of dairy cows

The objective of this study was to evaluate the effect of administration of scopolamine (a parasympatholytic drug) immediately after delivery, on uterine involution in dairy cows. The cows were divided into two groups: group T (treated with scopolamine butylbromide 40 mg/100 kg P.V., within 24 h of delivery) and group C (treated with 2 ml/q of saline solution). The cows were monitored at T0, within 24 h of delivery, T7, T14, T28 and T40 respectively 7th, 14th, 28th and 40^th day postpartum, by measuring the levels of hydroxyproline (HYP), an important marker of uterine involution; by ultrasound examination for the measurement of the diameter of uterine horns and of blood flow in the middle uterine artery; and by evaluation of reproductive indices. HYP showed higher concentrations in the T group than in the C group at all times, but the difference was significant at T7 and T40. Uterine diameters were reduced from T7 to T40, with lower values in the T group, as compared to the C group; the pulsatility index (PI) of the middle uterine artery increased in the T group compared to the C group, with a statistically significant difference at T7. There was a better conception-delivery interval and higher pregnancy rate in the T group compared to the C group. It is likely that scopolamine blocked the uterine contractions in postpartum, for the duration of its half-life. After cessation of its pharmacological effect, the uterus may have started to contract more effectively. These results suggested that scopolamine could be useful as a pharmacological approach to postpartum management.

Effect of exogenous estradiol Benzoate on uterine blood flow in postpartum dairy cows

The objective of this study was to assess the uterine blood flow following estradiol benzoate administration in Holstein-Friesian dairy cows by trans-rectal color Doppler ultrasonography. Six healthy lactating Holstein-Friesian cows were examined daily for 10 days starting at 4 weeks postpartum. All the cows, which were clinically healthy based on vaginal mucus scoring and endometrial cytology, were examined by trans-rectal Doppler ultrasonography to measure pulsatility index (PI), resistance index (RI), time average maximum velocity (TAMAX), blood flow volume (BFV) and diameter in the uterine arteries ipsilateral and contralateral to the previously pregnant uterine horn. On the third day of the experiment, the six cows were administered 10 mg intramuscular injection of estradiol-17β (E₂).Blood samples were collected at the time of daily examination for the assessment ofE₂concentrations.The PI and RI values decreased while TAMAX, BFV and diameter of uterine arteries increased in response toE₂ administration (P < 0.05).There was a high correlation between both the ipsilateral and contralateral uterine arteries for all variables that were studied(r = 0.860, P < 0.0001, r = 0.922, P < 0.0001, r = 0.651, P < 0.0001, r = 0.879, P < 0.0001, r = 0.861, P < 0.0001 for the PI, RI, TAMAX, BFV and uterine arteries diameter, respectively).In conclusion, the greater blood concentrations ofE₂may be responsible for the greater TAMAX, BFV, increased diameters and decreased PI and RI of the uterine arteries during the puerperium in dairy cows.

Sonogram of coccygeus muscle in dairy cows with different gestational ages

BACKGROUND

The change in size and weight of the female reproductive organs during gestation and birth might be affect the perineal muscles and this condition in dairy cow not been reported. This study aimed to assess the ultrasonographic image of coccygeus muscle in 11 inseminated dairy cows with different gestational ages and postpartum.

METHODS

Gestational age was calculated based on the record of artificial insemination and confirmed by using transrectal brightness mode ultrasonography. Perineal hair between the sacrum and ischium bones was shaved along 3-5 cm before being ultrasound. The images of perineal area were obtained by transcutaneous ultrasound using a 5.0 MHz transducer. The thickness and intensity of the coccygeus muscle were measured and analyzed by gestational status and postpartum to show the differences.

RESULTS

The results showed that the thickness of coccygeus muscle increased with the increase in gestational age. Muscle intensity only increased at young gestational age. However, it decreased with the increase in gestational age (P < 0.05).

CONCLUSIONS

The ultrasound image of coccygeus muscle was affected by gestational status, thus this method may be used as one of the new methods of indirect gestational detection on dairy cows.

Effects of induced endometritis on uterine blood flow in cows as evaluated by transrectal Doppler sonography

This study was conducted to evaluate the effects of induced endometritis on uterine blood flow in cows. Transrectal Doppler sonography was performed on uterine arteries of six cyclic cows before and for 4 days after inducing acute endometritis by intrauterine infusion of 720 mg of policresulen, and for 4 days of the following estrous cycle. Time-averaged maximum velocity (TAMV) increased (p < 0.001) and pulsatility index (PI) decreased (p < 0.0001) within 1 h of policresulen administration, and did not change (p > 0.05) in the next 4 days of the same cycle. TAMV and PI values in the subsequent cycle did not differ (p > 0.05) from the values measured before infusion and showed no changes (p > 0.05) within the cycle. Blood flow parameters were not related (p > 0.05) to plasma concentrations of progesterone and estrogen. All cows showed an acute endometritis determined by histopathological findings of biopsy samples taken 1 day after infusion and fibrotic endometrial alterations detected in the subsequent cycle. No relationships were observed between fibrotic changes of the endometrium and uterine blood flow during either cycle. In conclusion, acute inflammation is accompanied by a rise in uterine blood flow, but fibrotic alterations do not seem to be related to Doppler sonographic findings.

Investigations of mammary and uterine blood flow in relation to milk yield, postpartum disease, and pregnancy result in dairy cows

The objective was to determine the blood flow variables in the uterine arteries and the pudendoepigastric trunks, which supply the mammary gland, and relate these variables to the occurrence of uterine disease, milk yield, and pregnancy result. To achieve this, 119 multiparous German Holstein cows were examined using color Doppler sonography once during the dry period and on Days 7, 14, 28, 42, 56, 66, 76, 86, and 96 postpartum (pp). Cows with retained fetal membranes or metritis had a higher blood flow volume and time-averaged maximum velocity and a lower pulsatility index in the uterine arteries on Days 7, 14 and 28 pp (P < 0.05). Milk yield was correlated with blood flow volume in the pudendoepigastric trunks on examination Days 7 to 96 pp with the exception of Day 76 (P < 0.05), and with time-averaged maximum velocity on Days 7 and 14 pp (P < 0.05). The pulsatility index was greater in the left pudendoepigastric trunk on examination Days 7 to 76 pp than in the right pudendoepigastric trunk (P < 0.05). Milk yield did not affect pregnancy result and was not related to uterine perfusion. Increased uterine perfusion in cows with retained fetal membrane and metritis may be due to increased uterine size attributable to delayed involution. High mammary perfusion in high-yielding cows is due to an increased demand for nutrients and oxygen. Color Doppler sonography is a useful method for the investigation of the effect of uterine disease on uterine blood flow and of the effect of milk yield on mammary perfusion.

Ultrasonographic Doppler Use for Female Reproduction Management

Transrectal color Doppler ultrasonography is a useful technique to get new information about physiologic and pathophysiologic alterations of the uterus and ovaries in female cattle. During all reproductive stages characteristic changes in uterine blood flow are observed. Cows with puerperal disturbances show delayed decrease in uterine blood flow in the first few weeks postparturition compared with healthy cows. Measurement of follicular blood flow is used to identify normally developing follicles and predict superovulatory response. Determination of luteal blood is more reliable than B-mode sonography to distinguish between functional and nonfunctional corpora lutea. Color Doppler ultrasonography is a promising tool to improve reproductive management in female cattle.

Effect of uterine size on fertility of lactating dairy cows

There are multiple reasons for reduced fertility in lactating dairy cows. We hypothesized that one cause of reduced fertility could be the overall size of the reproductive tract, particularly the uterus, given well-established uterine functions in many aspects of the reproductive process. Thus, the objectives of this study were to evaluate the variability in uterine size in primiparous and multiparous dairy cows and to analyze whether there was an association between uterine size and fertility, particularly within a given parity. Lactating Holstein dairy cows (n = 704) were synchronized to receive timed artificial insemination (TAI) on Day 81 ± 3 of lactation by using the Double-Ovsynch protocol (GnRH-7d-PGF-3d-GnRH-7d-GnRH-7d-PGF-56h-GnRH-16h-TAI). At the time of the last injection of PGF, uterine diameter was determined at the greater curvature using ultrasound, uterine length was determined by rectal palpation, and uterine volume was calculated from these two measurements. Blood samples were also taken to measure progesterone to assure synchronization of all cows used in the final analysis (n = 616; primiparous, n = 289; multiparous, n = 327). Primiparous cows had greater percentage pregnant/AI (P/AI) compared to multiparous cows (49.8% vs. 39.1% at 67 days of pregnancy diagnosis, P = 0.009). Diameter, length, and volume of the uterus were larger in multiparous than in primiparous cows (P < 0.001). For multiparous cows, uterine diameter and volume were smaller in cows that became pregnant compared to cows that were not pregnant to the TAI with a similar tendency observed in primiparous cows. Logistic regression and quartile analysis also showed that as uterine volume increased, there was decreased P/AI in either primiparous or multiparous cows. Thus, there is a negative association between uterine size and fertility in lactating dairy cows with a larger uterus associated with reduced fertility, particularly for multiparous cows.

Transrectal Doppler sonography of uterine blood flow during the first two weeks after parturition in Simmenthal heifers

Transrectal Doppler sonography was used to evaluate uterine blood flow during the first two weeks after parturition in six primiparous Simmental cows. The uterine blood flow was evaluated on the day of parturition (Day 0), once daily from Days 1 to 8 and then every other day until Day 14. Blood flow was quantified by determining the diameter (D), the time-averaged maximum velocity (TAMV), the pulsatility index (PI) and the blood flow volume (BFV) of the uterine arteries ipsilateral and contralateral to the formerly pregnant uterine horn. During the first four days after calving D, TAMV and BFV declined (ipsilateral: TAMV 70%, BFV 87%, contralateral: D 47%, BFV 84%; p < 0.05), while PI increased (ipsilateral 158%, contralateral 100%; p < 0.05) distinctly. Between Days 4 and 14 only the ipsilateral D (12%) and the BFV of both arteries (ipsilateral 5%, contralateral 8%) decreased (p < 0.05). Blood flow variables were very strongly correlated with each other (r > ±0.75, p < 0.05), with negative correlations with PI and positive correlations with all other investigated factors. Overall, this study revealed characteristic changes in uterine perfusion during the first two weeks after parturition in cows that were pronounced during the first four days postpartum.

The effect of lactation on post-partum uterine involution in Holstein dairy cows

The objective was to examine the effect of lactation on uterine involution in post-partum dairy cows. Holstein primiparous cows were used (n = 19, mean age: 3.9 ± 0.1 years). At calving, cows were randomly assigned to one of two treatment groups, lactating (n = 11) or non-lactating (i.e. dried off at calving, n = 8). Examination of the reproductive tract was carried out by ultrasonography twice weekly until week 7 post-partum. Blood samples were collected twice weekly for the analysis of progesterone to indicate the resumption of cyclicity and metabolites indicative of energy status. Uterine involution was assessed in terms of size of the uterine horns, uterine body diameter and uterine fluid volume as assessed by the amount of non-echogenic material measured by ultrasound and position of the uterus. Vaginal mucous score was taken on day 28 post-partum for the assessment of uterine inflammation. Resumption of cyclicity (serum progesterone > 1 ng/ml) had occurred in both groups on average by day 21 post-partum. Concentrations of non-esterified fatty acids and beta-hydroxybutyrate were higher, whereas concentrations of glucose, insulin and IGF-1 were lower (p < 0.05) in lactating compared to non-lactating cows. Lactating cows had a smaller mean uterine body diameter (p < 0.05) than non-lactating cows from days 28 to 42 post-partum (day 28: 20.2 ± 1.3 vs 24.9 ± 1.5 mm, respectively) and had a lower mean uterine fluid volume up to day 49 (p < 0.05). By day 49, there was no difference in uterine diameter (15.2 ± 1.8 vs 15.2 ± 1.6 mm) or uterine fluid volume (0.11 ± 0.38 vs 0.18 ± 0.46) between lactating and non-lactating cows, respectively. Vaginal mucous score revealed no evidence of uterine inflammation in either group. In conclusion, while lactation induced significant alterations in metabolic status, it did not have a major effect on the rate of uterine involution as defined in this study.

Effects of caesarean section on serum levels of NT-proBNP

OBJECTIVE

To determine the effects of delivery by caesarean on serum levels of N-terminal fragment of precursor protein brain-type natriuretic peptide (NT-proBNP).

METHODS

Serum NT-proBNP levels were determined longitudinally at 24 and 36 weeks of gestation (GW) and on post-partum day 3 and month 1 (PPD3 and PPM1, respectively) in 78 women with normotensive singleton pregnancies. Thirty-nine women underwent caesarean delivery. Plasma renin activity (PRA) and plasma aldosterone concentration (PAC) were determined on PPD3. Effects of maternal demographic characteristics on NT-proBNP levels were also analysed.

RESULTS

NT-proBNP levels (pg/ml) either in pregnancy or on PPM1 did not differ between women with vaginal and caesarean deliveries (44 ± 24 vs 41 ± 30, 24 GW; 37 ± 22 vs 29 ± 22, 36 GW; 43 ± 28 vs 39 ± 24, PPM1, respectively). Levels on PPD3 were significantly higher (94 ± 105 vs 247 ± 186, P < 0.0001) in women with caesarean delivery. Among women with caesarean delivery, a larger rise of NT-proBNP on PPD3 occurred in nulliparous than in multiparous women (319 ± 232 vs 185 ± 107, P = 0.023), while no rise occurred among multiparous women with vaginal delivery (108 ± 115 vs 47 ± 27). NT-proBNP levels on PPD3 were significantly and negatively correlated with PRA, PAC and maternal weight loss after childbirth on PPD3. These 3 variables on PPD3 were significantly lower in women undergoing caesarean than vaginal delivery (0.8 ± 0.4 vs 1.9 ± 1.4 ng/ml/h for PRA; 70 ± 38 vs 136 ± 88 pg/ml for PAC; 2.7 ± 1.2 vs 4.3 ± 1.1 kg for weight loss, each P < 0.0001).

CONCLUSIONS

The transient post-partum rise in serum NT-proBNP may reflect transient volume overload after parturition and is remarkable in nulliparous women, especially after caesarean section.

Uterine artery blood flow volume in pregnant women with an abnormal pulsatility index of the uterine arteries delivering normal or intrauterine growth restricted newborns

The aim of this study was to assess and compare uterine artery (UtA) blood flow volume in pregnant patients with an abnormal uterine Doppler pulsatility index (PI) who delivered fetuses with an appropriate weight for gestational age (AGA) or with intrauterine growth restricted (IUGR). We prospectively recruited singleton pregnancies with abnormal uterine arteries P.I. between 18 and 38 weeks of gestation regardless of estimated fetal weight (EFW). Vessel diameter and blood flow velocity were measured along the UtA upstream to the vessel bifurcation in both the right and left UtAs. Uterine blood flow volumes measured in these pregnancies were compared to historical Control-pregnancies. Forty-three patients delivered at term a normal weight newborn (AGA-pregnancies). Thirty patients delivered growth restricted newborns at 32 weeks (i.r. 29-36w) with a median weight of 1160 gr (i.r. 1000-2065 gr) (IUGR-pregnancies). At mid-gestation (18 + 0 - 25 + 6 weeks + days of gestation) a significantly lower uterine blood flow volume per unit weight was observed between the two study groups and compared to controls: 142 ml/min/kg in IUGR-pregnancies, 217 ml/min/kg in AGA-pregnancies and 538 ml/min/kg in Control-pregnancies. These striking differences in blood flow volume were already present at mid-gestation, at a time when EFW was still normal. In late gestation (27 + 0 - 37 + 6 weeks + days of gestation), pregnancies with an abnormal uterine P.I. showed persistently low UtA flow (<50% of controls) even when corrected for fetal weight: 81 ml/min/kg in IUGR-pregnancies, 105 ml/min/kg in AGA-pregnancies, and 193 ml/min/kg in Control-pregnancies; p < 0.0001. Our findings are consistent with other recent studies regarding the association between reduced uterine blood flow volume and fetal growth restriction. However, the study brings new insight into the finding of abnormal uterine P.I. in normally grown fetuses typically dismissed as "falsely abnormal" or "false positive" findings. Our study suggests that blood flow volume measurement may serve as a new tool to assess this group of patients and possibly those with ischemic placental diseases that may provide some basis for therapeutic interventions.

Investigation of mammary blood flow changes by transrectal colour Doppler sonography in anEscherichia colimastitis model

The objectives of this preliminary investigation were to evaluate the feasibility of transrectal colour Doppler sonography (TCDS) for determining blood flow of the pudendoepigastric trunk in cows with experimentally inducedEscherichia coliMastitis. Five primiparous Holstein dairy cows, 4–6 months after calving, were examined in two trials. All monitored udder quarters were initially clinically healthy, somatic cell count (SCC) was <50 000 cells/ml and bacteriologically negative. The blood flow of the left and the right pudendoepigastric trunk was described by the blood flow volume (BFV). In the methodological part of the study, the intra-observer precision of the method was evaluated. The coefficients of variation of the BFV were 7·1% for the left and 9·4% for the right pudendoepigastric trunk. The intraclass correlation coefficients of the BFV were 0·99 (P<0·001) for the left and 0·75 (P=0·004) for the right vessel. BFV did not differ significantly between the left and the right side nor between pre- and post-milking nor between oestrus and dioestrus. In the experimental part of the study, significant differences of increasing BFV between 0 and 12 h p.i. (post infectionem) (P=0·043) and decreasing BFV between 12 and 24 h p.i. (P=0·043) were discovered for the pudendoepigastric trunk of the infected right side. In the left-right (control-infection) comparison a significant increase of the right BFV was observed at 12 h p.i. (P=0·043). The difference of an increasing SCC correlated positively with the difference of an increasing BFV between 0 and 12 h p.i. (Spearman's ρ=1·00;P=0·043) for the right infected side. It was shown that TCDS is a reproducible technique for investigating pathological mammary blood flow changes at an early stage of acute mastitis.