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These studies aimed to determine if shearing ewes at the second or last third of gestation modify the uterine and placentome blood flow, placentome size, and maternal progesterone concentration. Pregnant ewes were assigned to four groups of 12 ewes each according to the gestation period: mid-pregnancy sheared (on day 90 of pregnancy) or unshorn group; and late-pregnancy sheared group (on day 121 of pregnancy) or unshorn group. In both experimental periods, using spectral Doppler ultrasonography, placentomes and uterine artery blood flow and placentome size were evaluated 14 days before and 6 days after shearing. An additional measurement was performed 26 days after shearing in mid-pregnant ewes. Serum progesterone concentration was measured before shearing 4, 24, 72 h, and 22 days after shearing. The uterine artery's end-diastolic velocity (EDV) tended to be greater in the sheared than in the non-sheared ewes (p = 0.1). Peak systolic velocity (PSV) and EDV of placentome increased (p = 0.05 and p = 0.008, respectively) on day 26, accompanied by an increase in placentome area (p = 0.035) in mid-pregnant ewes. In late-pregnant ewes, uterine artery and placentome blood flow and size did not vary. Progesterone concentration varied with time but was not affected by shearing. In conclusion, shearing triggered an increase in placentome size and some changes in blood flow only when ewes were sheared during the second third of their pregnancy. Shearing ewes either the second or last third of gestation did not affect uterine artery blood flow and progesterone secretion., (© 2024 Wiley‐VCH GmbH. Published by John Wiley & Sons Ltd.)

Objective: To evaluate the changes in flow velocities of the middle cerebral artery before and after a carotid compression maneuver using transcranial color-coded duplex sonography (TCCD) in healthy anesthetized dogs under mechanical ventilation., Design: Prospective study., Setting: University teaching hospital., Animals: Eleven healthy adult dogs., Interventions: A 5-second carotid occlusion maneuver was performed to evaluate cerebral autoregulation (CA)., Measurements and Main Results: After 10 minutes of stable anesthesia, the middle cerebral artery was evaluated by TCCD. Dogs were positioned in sternal recumbency with the head raised to the level of the phlebostatic axis. The systolic peak velocity (Vp) was measured using pulsed Doppler mode. CA was evaluated through the transient hyperemia test (THT), which assesses changes in the Vp after a 5-second transient compression of the ipsilateral common carotid artery and is expressed as the ratio between the Vp flow before and after carotid compression. The Vp before and after carotid occlusion was compared using the Wilcoxon signed-rank test. The median Vp of the middle cerebral artery after the carotid compression maneuver was significantly higher than the median Vp before compression (median [interquartile range, IQR]: 47.7 cm/s [34.3] vs 64.1 cm/s [24.4]; P = 0.003). The median THT obtained was 1.20 (IQR: 0.37)., Conclusions: The current study demonstrated a significant increase in the Vp of the middle cerebral artery after a 5-second temporary occlusion of the ipsilateral carotid artery in healthy anesthetized dogs under mechanical ventilation. These findings suggest that the noninvasive TCCD methodology could be valuable for assessing CA in dogs. Additional studies using this technique in neurocritical animals are required to confirm its usefulness., (© Veterinary Emergency and Critical Care Society 2024.)

The main goals of this study were to document and compare the normal ranges of testicular haemodynamic parameters in pre- (aged 8-12 months; n = 4) and postpubertal (aged 24-259 months; n = 16) Miranda donkeys in the breeding season, and to correlate animal biometric data and testicular Doppler indices with basic semen quality parameters of sexually mature jacks. Colour and pulsed-Doppler ultrasonography were employed to assess blood flow in the left and right distal supratesticular artery (DsTA) and their marginal branches (marginal arteries-MA). Peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI) and resistive index (RI) were evaluated in both blood vessels, and TAMV (time-averaged mean velocity), TABF (total arterial blood flow) and TABF rate (TABF-R) were calculated for MA. The mean diameter of MA was greater (p < 0.05; 0.24 ± 0.05 vs. 0.19 ± 0.05 cm; mean ± SD) but TABF-R was less (p < 0.05; 0.004 ± 0.004 vs. 0.02 ± 0.01 mL/s/cm 3 ) in sexually mature donkeys compared with prepubertal animals. Apart from RI values for the right testicle of prepubertal donkeys, PI and RI were consistently greater (p < 0.05) in DsTA compared with MA. Significant correlations were found among select biometric and haemodynamic attributes of the testes (height, width and length, TV, TTV and PSV-ST) and ejaculate characteristics (volume, sperm defects-total, head and midpiece) in sexually mature donkeys (n = 8). The present results highlight the importance of scrotal ultrasonography for the reproductive assessment of jacks and provide reference values, based on the available subpopulation of Miranda donkeys that can be used in their clinical and reproductive management and research, or conservation programmes., (© 2024 Wiley‐VCH GmbH. Published by John Wiley & Sons Ltd.)

Cardiovascular changes have been reported in late pregnancy in mares. However, there are no data on changes in peripheral blood flow. Doppler ultrasound represents a sensitive method for assessing the blood flow directed to the hoof. The aims of this study were to evaluate the blood flow parameters of the lateral palmar digital artery (LPDA) in pregnant mares and to assess intra- and interrater agreement between two observers with different levels of experience. The LPDAs of pregnant Italian Standardbred mares were examined. The vessels were located with B-mode ultrasound and analyzed with color and pulsed wave Doppler. The following parameters were recorded by the operators: heart rate (HR), peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI). Measurements were performed between 2 and 3 months of gestation (T1), in the last month of pregnancy (T2) and a week after delivery (T3). Seventeen mares aged 3-18 years met the inclusion criteria. Ultrasound examinations of the LPDA were subjectively easy to perform and well tolerated by the mares. Interrater and intrarater agreement were good and moderate, respectively. The HR was higher at T2 than at T1 and T3. The PSV and RI changed significantly during pregnancy, with higher values at T2 and T3, whereas the EDV remained unchanged throughout the examination. Doppler examination showed that peripheral flow changes were present in mares in late pregnancy. However, the persistence of higher values after delivery invites further investigation to assess the correlation between metabolic/endocrine changes related to pregnancy and Doppler parameters., (© 2024 American College of Veterinary Radiology.)

The objective of the present study was to demonstrate the blood flow velocities, blood flow rate (BFR; bpm) with the accurate ratio of both systolic and diastolic velocities points (S/D) in addition to Doppler indices (resistive and pulsatility index [RI and PI]) in both fetal [fetal heart (FH), fetal abdominal aorta (Ab. A), and umbilical artery (UM.A)] and maternal [Middle uterine artery (MU.A)] sides during the last month of gestation. Ten Zaraibi (Egyptian Nubian) goats weighing 40-50kg and aged from 5-7 years were examined twice per month till reached the last month of pregnancy. Then all females were examined every 5 days starting from day -35 till day -1 before kidding.The pregnant goats were examined by ultrasonic and Doppler indices were recorded with Doppler scanning (7.5 -12 MHz, with colored and spectral graph to form the perfect wave to assess Doppler measurements). The obtained data were analyzed using analysis of variance. Results indicated that on the fetal side; the maximum point of velocity (MSV; cm/sec) in the FH and BFRwere elevated from day -35 till day -10 with a slight decline at days -5 and -1 at the peripartum period (P < 0.05), while FH.PI and S/D ratio declined till day -1(P < 0.05). In addition, the fetal Ab. A, and UM.A PI, RI, and S/D ratio declined from day -35 till day -1 at the peripartum period with a significant increase in the peak systolic velocity (PSV) and BFR(P < 0.05). However, non-significant changes in the end diastolic velocity (EDV) were detected. On the maternal side, the MU.A PI and S/D declined from day -35 till day -1 with an elevation of both PSV and BFRat the same time points (P < 0.05). In conclusion, the Doppler evaluation of fetal and maternal blood flow vessels is important to give complete information that directly affects the health status of the mother and fetus., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Objective: To investigate hemodynamics and morphology of hip joint vasculature in cats with the use of color and pulsed-wave Doppler ultrasonography., Animals: 30 client-owned healthy skeletally immature cats presented for routine examinations between September 7, 2022, and March 25, 2023., Methods: Cats between 3.5 to 18 months old with healthy hip joints and Hct within reference ranges (26% to 44.2%) were eligible for inclusion. Color and pulsed-wave Doppler ultrasonography was performed without sedation. Peak systolic velocity (PSV), mean diastolic velocity (MDV), resistance index (RI), and pulsatility index (PI) were measured for major arteries of the hip joints., Results: Intermediate pulsatility, resistance to flow, and pandiastolic anterograde flow were evident for all arteries evaluated for each joint except for the ligamentum capitis ossis femoris artery (LCOFA). Spectral waveforms for the LCOFA showed a low-resistance pattern with continuous forward diastolic flow. No significant differences were found in the mean PI or MDV between the left and right sides for the ascending branch of the lateral circumflex femoral artery or in the mean PI of the ascending branch of the medial circumflex femoral artery. Mean PSV of the LCOFA was lower (but nonsignificantly) for left hip joints vs right hip joints, whereas other values were often higher on cats' left side vs their right., Clinical Relevance: This study provided insight into the morphology and hemodynamics of the femoral head vasculature in skeletally immature cats and showed Doppler ultrasound values to study the clinically normal blood supply to hip joints in cats.

Background: No study has been performed regarding the effects of oral administration of propranolol on pulse-wave spectral Doppler indices of major abdominal vessels in healthy adult cats., Objective: The objective of this study was to assess the pulse-wave spectral Doppler indices of abdominal aorta, caudal vena cava, and portal vein in clinically normal adult domestic short-haired (DSH) cats, before and after propranolol ingestion., Methods: Twenty intact adult client-owned DSH cats were evaluated (10 males and 10 females). A duplex Doppler ultrasonography machine with a 10-MHz frequency linear transducer was used. Peak systolic velocity, end-diastolic velocity (EDV), resistive index (RI), pulsatility index (PI), and pressure gradient were measured. All the cats received 1 mg/kg of propranolol tablet, and after 2 h, ultrasonography measurements were repeated., Results: The mean RI of the aorta and caudal vena cava significantly decreased in male cats following oral administration of propranolol after 2 h (p = 0.03, p = 0.02). In the caudal vena cava, the PI decreased from 2.98 ± 0.62 to 1.15 ± 0.19 post-propranolol ingestion (p = 0.01). The mean EDV in the caudal vena cava of males and portal veins of females significantly decreased after propranolol ingestion (p = 0.04, p = 0.02)., Conclusions: This study showed that propranolol decreased the PI of the aorta and PI and RI of the caudal vena cava in healthy normal cats 2 h post-propranolol ingestion at the dosage of 1 mg/kg., (© 2023 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Contrary to its widespread use in human cases, the use of Doppler ultrasonography is only recently becoming prevalent in farm animals. This study aimed to determine the effects of maternal metabolic and clinical changes on fetal hemodynamics during pregnancy toxemia with the doppler examination of umbilical cord. In the study twenty ewes with a single healthy fetus were included in the study. At the end of the 120th day of pregnancy, 20 single-bearing pregnant ewes were randomly categorized into two groups. Ewes in the control group were fed to meet all nutritional requirements. On the other contrary, the experimental ewes were fed to meet equivalent to 50 % of the daily needs and then fasted for 96 h. Doppler ultrasonographic examinations of umbilical cord were performed once every two days and once a day during fasting. Beta hydroxybutyric acid (BHBA) concentration was measured by taking blood from sheep on examination days. Pulse systolic velocity (PSV), end diastolic velocity (EDV), PSV/EDV, pulsatility index (PI), resistance index (RI), and fetal heart rate (FHR) as well as BHBA values and how those parameters has changed over time (time by treatment effect) due to energy deprivation during pregnancy were evaluated using repeated measure analysis of variance. No clinical signs were observed in both toxemia and control groups during restricted feeding. BHBA concentration increased and there was a significant time, time by treatment and main effect of treatment effect between groups. No significant main effect of treatment and time by treatment interaction was observed in the changes of PI, RI, FHR, and systolic/diastolic velocity values over time in both groups. FHR was reduced over time, and there was a significant time effect in FHR in both groups. Although doppler indices didn't increase, both PSV and EDV values increased significantly in the pregnancy toxemia group compared with the controls (Time P = 0.03, time by treatment interaction P < 0.05) and the main effect of treatment P < 0.05). The marked increase in blood velocities (PSV and EDV) in the umbilical cord is probably due to the compensatory functioning for excessive energy deprivation of the fetus. Therefore, PSV and EDV might be a valuable indicator for evaluating the fetus's health status during the management of the PT., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Although Doppler ultrasonography (USG) is frequently used in human medicine to evaluate placental function and fetal well-being, studies in veterinary medicine are limited. Thus, this study aimed to determine the relationship between placentome perfusion and echotexture and endocrine changes during the last stages of pregnancy in cows using B-mode/Doppler USG and reveal the effects of hormonal changes on placentome and uterine artery hemodynamics. The animals consisted of 12 pregnant Swiss Brown cows 3.8 ± 0.34 years old with at least one birth. Imaging with USG was continued for 1 month, thrice weekly, until delivery. To determine serum progesterone (P4), total estrogen, and cortisol levels, blood was drawn from the tail vein immediately after USG examinations. Contrast (CON), homogeneity (HOM), and mean gray value (MGV) were determined by placentome echotexture analysis. Color Doppler perfusion areas (A mix) and power Doppler perfusion areas (A red) of the placentome, pulse rate (PR), pulsatility index (PI), resistance index (RI), blood flow velocity (BFVe), blood flow volume (BFVo), and diameter (DM) in the spectral analysis of uterine artery values were collected. ImageJ was used to analyze the B-mode images, and PixelFlux (Chameleon® Software, Münster, Germany) was used to calculate the placentome perfusion values and hemodynamic parameters of the uterine artery in Doppler images. In the last month of pregnancy, there was no statistical difference in the placentome echotexture values CON and HOM. However, MGV increased close to birth (P < 0.001). Placentome perfusion level and area did not change significantly but were found to decrease numerically 2 days before delivery (P > 0.05). Uterine artery PR increased from 62.36 bpm on day 25 prepartum to 81.42 bpm at birth (P < 0.05). The P4 concentration decreased in the last month of pregnancy, whereas an increase was detected in estrogen and cortisol during this period (P < 0.05). In the uterine artery of pregnant cornu, RI and PI were negatively correlated with BFVe (P < 0.01). Based on this study, echotextural differences were observed in placentomes in the last stage of pregnancy in cows, and there were significant changes in placental and uterine artery blood flow. These changes may be related to placental maturation, especially on the days close to birth., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

A 12-year-old neutered male Chihuahua was diagnosed with acute brain infarction in the right middle cerebral artery (MCA) territory. Transcranial Doppler ultrasonography (TCD) was performed to assess the local cerebral blood flow at the time of diagnosis and after 4 and 31 hr. Initially, the right MCA retained blood flow but with a lower cerebral blood flow velocity (CBFV; 14.9 cm/sec) than the left MCA (27.9 cm/sec). The TCD vascular resistance variables were higher in the right than in the left MCA. An increase in the CBFV and a decrease in TCD vascular resistance variables were observed, consistent with improvements in neurological symptoms. TCD can be a non-invasive, and easy-to-use modality for bedside monitoring of cerebral edema and infarction.

Background: Ultrasonography is one of the most important techniques that enable the detection and monitoring of pregnancy. One such study using this technique is the assessment of the hemodynamics of fetal and umbilical blood vessels. However, there is little data on blood flow in the placentomes, which is the basic structural unit of the sheep's placenta. Therefore, the aim of this study was to determine the Doppler parameters in the arterial vessels of the caruncles, cotyledons and the umbilical cord as well as measuring venous flow rates during the entire gestation period of the sheep. Additionally, the usefulness of various other ultrasound parameters in the early diagnosis of pregnancy in sheep was analyzed., Results: Most of the Doppler parameters in umbilical, cotyledonary and caruncular arteries were significantly correlated with the day of pregnancy (p < 0.01). In the early stages of pregnancy, the peak systolic velocity (PSV), regardless of the location of the artery, was significantly lower than that in the later stages of pregnancy (p < 0.01). PSV was also found to be significantly higher in the umbilical artery than in the cotyledonary and caruncular arteries (p < 0.01). Until the 50th day of pregnancy, the end diastolic velocity (EDV) was not found in the umbilical and cotyledonary arteries. EDV was significantly higher in the caruncular arteries than in the cotyledonary and umbilical arteries (p < 0.01). The resistance index (RI) and pulsatility index (PI) in the early stages of pregnancy were found to be significantly higher than that in the later stages of pregnancy (p < 0.01). The RI and PI were significantly lower in the caruncular arteries than in the arteries of the cotyledons and umbilical cord (p < 0.01). In the umbilical vein, all Doppler parameters were observed to be significantly higher than those in the placentomal veins (p < 0.01 or p < 0.05). Using transrectal ultrasound, pregnancy was detected between 20 and 28 days after mating. The ovaries were observed to have corpora lutea, the diameter of which was fairly consistent from the 17th to the 56th day of pregnancy., Conclusions: It has been demonstrated that both the location of the arterial vessel in the placental-umbilical circulation and the gestational age have a significant impact on hemodynamic parameters. The results also provide new insights about the blood flow in caruncular and cotyledonary arteries, which could contribute to a more holistic understanding of hemodynamic changes in the placentas of sheep. Analyzing haemodynamic parameters in the umbilical and placental veins are preliminary studies in sheep, but it could inspire further research in this field. Furthermore, the research conducted confirms the practicality and convenience of transrectal ultrasonography in the early diagnosis of pregnancy in sheep and also indicates that the identification and imaging of the corpus luteum using B-mode ultrasonography can be a very early and simple method of confirming effective mating in sheep., (© 2022. The Author(s).)

Objective: To investigate the association between changes in cerebral blood flow and electrographic epileptic seizure in dogs using transcranial Doppler ultrasonography (TCD)., Animals: 6 healthy Beagle dogs., Procedures: Each dog was administered pentetrazol (1.5 mg/kg/min) or saline (0.9% NaCl) solution under general anesthesia with continuous infusion of propofol. Both pentetrazol and saline solution were administered to all 6 dogs, with at least 28 days interval between the experiments. Blood flow waveforms in the middle cerebral artery and the basilar artery were obtained using TCD at baseline, after pentetrazol administration, and after diazepam administration. TCD velocities, including peak systolic velocity, end-diastolic velocity, and mean velocity and resistance variables, were determined from the Doppler waveforms., Results: During ictal-phase of pentetrazol-induced seizures, the TCD velocities significantly increased in the basilar and middle cerebral arteries while TCD vascular resistance variables did not change in either artery. The TCD velocities significantly decreased after diazepam administration. Systemic parameters, such as the heart rate, mean arterial pressure, systemic vascular resistance, cardiac index, end-tidal carbon dioxide, oxygen saturation, and body temperature, did not change significantly during seizures., Clinical Relevance: This study showed that cerebral blood flow, as obtained from TCD velocities, increased by 130% during ictal-phase of pentetrazol-induced seizures in dogs. The elevated velocities returned to baseline after seizure suppression. Thus, TCD may be used to detect electrographic seizures during the treatment of status epilepticus in dogs, and further clinical studies clarifying the association between changes in cerebral blood flow and non-convulsive seizure cases are needed.