Doppler ultrasonographic examination in sheep

Color Doppler Ultrasonographic Examination of Ovarian Grafts in Goats

The aim of this study was to evaluate the effectiveness of color Doppler ultrasonography for examination of the blood flow areas in superficial grafts after 7 or 15 days of heterotopic allotransplantation, comparing an in-ear subcutaneous area (IE) with an in-neck cervical intramuscular area (IN) in goats. To monitor the local blood flow in the graft areas, color Doppler signals were assessed daily until days seven and fifteen, when the left and right implants, respectively, were removed. The areas of blood flow around the transplanted ovarian fragments were significantly larger (p < 0.05) in the IE area compared to the IN area after 7 (IE: 4.70 ± 0.33A vs. IN: 3.67 ± 0.33B) and 15 (IE: 5.27 ± 0.21A vs. IN: 4.66 ± 0.22B) days of transplantation. A positive and significant correlation was observed between the area of blood flow and the day of assessment after 7 (IE: r = 0.43; p < 0.05) and 15 (IE: r = 0.52; p = 0.001; IN: r = 0.42; p = 0.001) days of transplantation. In conclusion, color Doppler ultrasonography can be used for real-time assessment of local blood perfusion in ovarian grafts, making it possible to identify alterations in the blood flow area in the period following a transplant procedure.

Maternal supplementation of curcumin-olive oil nanocomposite improves uteroplacental blood flow, placental growth and antioxidant capacity in goats

This experiment was designed to investigate the impact of curcumin-olive oil nanocomposite (CONC) supplementation on uteroplacental hemodynamics and ultrasonographic measurements as well as maternal oxidative status in midgestating goats. Twelve synchronized pregnant goats (85.58 ± 1.08 days of gestation; mean ± SD) were uniformly assigned to two groups (n = 6/group); the first group received daily oral supplementation of CONC (3 mg/kg body weight; nanocurcumin [NC] group) for 32 days, and the second group was offered physiological saline (control) following the NC group timeline. The goats of both groups were examined at 3-day intervals for middle uterine (MUA) and umbilical (UMA) arteries hemodynamics (pulsatility index [PI], resistive index [RI], systole/diastole [S/D] and blood flow rate [BFR]) and diameters, uteroplacental thickness (UPT), placentomes' diameter (PD) and echogenicity, steroid hormones (progesterone and estradiol 17β), oxidative biomarkers (total antioxidant capacity [TAC], catalase [CAT], malondialdehyde [MDA]), nitric oxide (NO) and blood cells DNA integrity. The UPT (p = 0.012) and PD (p = 0.021) values were higher in the NC group than in their counterparts' control group (D11-32). There were increases in diameter (p = 0.021 and p = 0.012) and decreases (p = 0.021, p = 0.016 and p = 0.041 [MUA]; p = 0.015, p = 0.023 and p = 0.011 [UMA] respectively) in Doppler indices (PI, RI and S/D) of the MUA and UMA in the NC group compared to the control group (D14-32). On D20-32 (MUA) and D14-32 (UMA), the NC goats had higher BFR than the control group (p = 0.021, 0.018 respectively). The means of blood cells with fragmented DNA were lower (p = 0.022) in the NC group than in the control group on Days 8 and 21 postsupplementation. There were increases in CAT and NO (D20-32; p = 0.022 and p = 0.004 respectively), and TAC (D17-32; p = 0.007) levels in the NC goats compared to the control ones. The NC group had lower (p = 0.029) concentrations of MDA than the control group on Day 20 postsupplementation onward. In conclusion, oral supplementation of CONC improved uteroplacental blood flow and the antioxidant capacity of midgestating goats.

Pulse wave Doppler ultrasound of umbilical cord in experimentally induced pregnancy toxemia in sheep

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.

Modern Imaging Techniques in the Study and Disease Diagnosis of the Mammary Glands of Animals

The study of the structure and function of the animals' mammary glands is of key importance, as it reveals pathological processes at their onset, thus contributing to their immediate treatment. The most frequently studied mammary diseases are mastitis in cows and ewes and mammary tumours in dogs and cats. Various imaging techniques such as computed tomography, positron emission tomography, magnetic resonance imaging, and ultrasonographic techniques (Doppler, contrast-enchanced, three-dimensional and elastography) are available and can be applied in research or clinical practice in order to evaluate possible abnormalities in mammary glands, as well as to assist in the differential diagnosis. In this review, the above imaging technologies are described, and the perspectives of each method are highlighted. It is inferred that ultrasonographic modalities are the most frequently used imaging techniques for the diagnosis of clinical or subclinical mastitis and treatment guidance on a farm. In companion animals, a combination of imaging techniques should be applied for a more accurate diagnosis of mammary tumours. In any case, the confirmation of the diagnosis is provided by laboratory techniques.

Ultrasonographic findings of the corpus luteum and the gravid uterus during heat stress in dairy cattle

The objectives of this study were to assess alterations in, echogenic appearance, size and blood flow in the corpus luteum, the placentomes and the blood flow in umbilical and uterine arteries that heat stress can cause in cooled pregnant dairy cows. Pregnant cows were allocated in two groups and the gravid uteri, along with the ipsilateral corpora lutea were examined during the winter (group W, n = 9) or the summer (group S, n = 10). The grey-scale ultrasound and colour flow imaging of the corpus luteum and placentome were performed. In addition, the umbilical and uterine artery diameters and haemodynamic parameters in the vessels were calculated. At the time of ultrasonographic examination, cortisol concentrations were higher, and progesterone levels tended to be lower in group S compared to group W. The grey-scale ultrasound evaluation of corpora lutea and placentomes was lower in group S compared to group W. The diameter of umbilical artery and the blood volume in the vessel were less in group S than in group W. We infer that heat stress affects foetal blood supply and possibly the structure of placentomes and corpora lutea, but it differently affects the blood flow characteristics in the umbilical and uterine arteries.

Clinical, ultrasonographic, bacteriological, cytological and histological findings during uterine involution in ewes with pregnancy toxaemia and subsequent reproductive efficiency

Objectives were to evaluate characteristics of uterine involution in ewes with pregnancy toxaemia during gestation and to study effects on subsequent reproductive performance. Pregnancy toxaemia was induced in ewes (A) by feeding an energy-deficient diet as confirmed by detecting β-hydroxybutyrate concentrations in blood indicative of this disorder. There was also a control group (C). Animals were evaluated until the 60th day post-partum using clinical and ultrasonographic examinations. Vaginal swab samples and uterine biopsy tissue samples were collected for bacteriological and cytological examination; biopsy samples were prepared for histological examination. Ewes were subsequently placed with rams and reproductive performance was ascertained. Post-partum, during the ultrasonographic examination of the uterus, ewes of Group A had caruncle and uterine lumen diameters, as well as a uterine thickness greater than ewes of Group C. Post-partum uterine blood flow volume was greater in ewes of the A than C group. Neutrophils predominated in vaginal samples, with the neutrophil proportion being less in ewes of Group A than C. There were no differences in the uterine involution process between groups. During the subsequent reproductive season, all the ewes of Group A lambed normally and produced viable lambs. It is concluded that there were no adverse effects on subsequent reproductive performance of ewes previously affected with pregnancy toxaemia, when appropriate health management was performed.

Higher doses of Melatonin affect ovarian and middle uterine arteries vascular blood flow and induce oestrus earlier in acyclic ewes

The present study aimed to evaluate the effect of a single intramuscular injection of melatonin on response of oestrus, rate of conception, ovarian and uterine blood supply during the non-breeding season. Melatonin powder was dissolved in dimethyl sulfoxide (DMSO) and olive oil and injected in two dose of 25 mg (MEL-1; n = 10) and 50 mg (MEL-2; n = 10) in May. Ten ewes were served as the control (CON). Results showed that oestrous response was higher in the MEL-2 group than in other groups (p < .01). The time to onset of oestrus in both the MEL-1 and MEL-2 groups was significantly shorter, compared with the CON group (p < .01). Pregnancy rates reached 80% and 90% at 45 days of gestation. Doppler indices of the right and left ovarian artery were lower in the melatonin groups than in normal groups (p < .01). Both Doppler indices in uterine arteries were not different among two treatment groups (p > .05), but there was a significant difference when compared with the CON group (p < .01), no difference found between two treatment group in the Doppler velocities of middle uterine arteries (p > .05). In conclusion, the definite changes in the studied parameters showed two novel findings; (a) the increase in melatonin dose results in increasing the blood flow expressed by increased Doppler velocities in fatty tailed ewes, (b) as well as, melatonin can initiate the breeding season regardless of the season earlier by 1-2 months in ewes.

Clinical, Ultrasonographic, Bacteriological, Cytological and Histopathological Findings of Uterine Involution in Ewes with Uterine Infection

The objectives of the study were (a) to study the characteristics of uterine involution in ewes that had developed subclinical uterine infection in the immediately post-partum period and (b) to evaluate effects of the infection in the subsequent reproductive performance of ewes. Uterine infection was induced in ewes (I, n = 10) by intrauterine inoculation of Escherichia coli; uninoculated controls were included (C, n = 12). Animals were examined at regular intervals before and post-inoculation. Clinical and ultrasonographic examinations were performed. Vaginal swab samples and biopsy uterine tissue samples were collected for bacteriological, cytological and histological examination. Finally, ewes were put to rams and reproductive performance was monitored. After challenge, it was ultrasonographically found that caruncular dimensions, myometrial thickness and diameter of uterine lumen were greater in I ewes. In these ewes, particular reduction of dimensions occurred during the second week post-partum, whilst in C ewes during the first week. The uterine artery diameter and the blood flow into the uterus were also greater in I than in C ewes. E. coli infection was more frequent and of longer duration in I than in C ewes: in 68.1% and 50.0% of ewes and 19.5 and 14 days, respectively. There was lower proportion of neutrophils and higher of lymphocytes in group I than in C. In inoculated ewes, there was histological evidence of uterine epithelial destruction, increased cellular infiltration, hyperaemia and extracasation, which persisted up to 42 days post-partum. During the subsequent reproductive season, all ewes in group I lambed normally and produced healthy and viable lambs. No significant difference in reproductive performance parameters were seen in I comparison to C ewes. It is concluded that the innate immunity of the uterus sufficed to counteract the bacterial infection, although the process of involution took longer than in healthy animals; moreover, the ultrasonographic examination is a useful means for assessment of the genital tract of ewes post-partum; finally, no adverse effects were noted in the subsequent reproductive performance of ewes.

Maternal stress in sheep during late pregnancy influences sperm quality in early puberty of the offspring

Stress at the end of sheep gestation can damage the reproductive development of young males. The aim of the present study was to evaluate the effects of LPS administration in the last third of sheep pregnancy on the reproductive parameters of prepubertal rams. Thirty-six pregnant nulliparous ewes (12 ± 2 months old; 45 ± 6 kg) were assigned to two treatments, LPS (E. coli; 0.8 μg kg^-1) and control (placebo/saline) administered in late pregnancy (120 days post-conception). The animals gave birth to 17 male lambs (11 LPS; 8 control). Reproductive development of the young rams was analyzed from 5 to 12 months of age. A completely randomized design in double factorial scheme was used. The data were analyzed by analysis of variance. The model included treatment (LPS; control), age as main effects and their interactions, and the animal as a repeated measure. Means were compared by the PDIFF-SAS (Pr > |t|) at P < 0.05. An effect of age was observed for scrotal circumference, testicular consistency, homogeneity of testicular parenchyma, vascularization, semen quantity and quality, and blood testosterone concentration (P < 0.05). LPS increased sperm defects (P < 0.05) but an interaction with age was not observed (P > 0.05) with higher abnormalities only during months 8 and 9 (P < 0.05) and not thereafter. In summary, LPS did not cause long-term damage to testicular morphology analyzed from the onset of puberty to sexual maturity. However, LPS treatment affected sperm morphology during early puberty of the offspring.

Uterine hemodynamics during a short-term progesterone synchronization protocol in ewes

Twenty-eight pluriparous and non-lactating Santa Inês sheep were synchronized with vaginal sponge and an intramuscular (IM) injection of 37.5 μg of cloprostenol on random days of the estrous cycle (D0); day 6 (D6), at 7:00 am, the devices were removed, and after 24 h (D7), GnRH analog (25 μg of lecirelin) was administrated. Fixed-time artificial insemination (FTAI) with cervical traction by the transcervical route was performed 52 to 58 h after sponge removal. Doppler velocimetry of both uterine arteries was performed on D0, D2, D4, and the morning of D6 (every 48 h), and then every 12 h from D6 to D8 (7:00 a.m. and 7:00 p.m.). We analyzed the peak systolic velocity (PSV), end-diastolic velocity (EVD), time-averaged maximum and mean velocity (TAMAX, TAMEAN), pulsatility index (PI), resistance index (RI), systolic/diastolic ratio (S/D), arterial diameter (AD), and blood flow volume (BFV), with the objective of evaluating the hemodynamic behavior of blood flow velocity parameters of the uterine artery during a short-term progesterone synchronization protocol in ewes. With respect to phases, we noted increases in the means of TAMAX and TAMEAN and decreases of EDV, PI, and RI (P < 0.05). S/D, EDV, TAMEAN, PI, RI, SD, AD, and BFV showed differences between the time of progesterone insertion and the estimated time of ovulation (which was considered the last evaluation) (P < 0.05). The PI and RI values were different when comparing the times of insertion and withdrawal of the progesterone device (PI 2.53-1.54 and RI 0.76-0.68) (P < 0.05). The PI was different with respect to side (P < 0.001), but no side effect was seen in the RI. In conclusion, the two uterine arteries behave differently under the effect of progesterone (intravaginal sponges) and the effect of estradiol during the follicular phase, and estrous phase was responsible for increasing uterine blood flow.

Early pregnancy diagnosis by semiquantitative evaluation of luteal vascularity using power Doppler ultrasonography in sheep

The aim of the study was to measure the area of coloured pixels captured in power Doppler examination of corpus luteum (CL) by a computer-assisted image analysis software and to evaluate the efficiency of the semiquantitative assessment of CL in early pregnancy diagnosis in sheep. Assessment of luteal vascularity was carried out on 30 Kivircik ewes with power Doppler ultrasonography daily from Day 12 to Day 19 post breeding. The mean area of coloured pixels of CL with pregnancy was found significantly higher than the area of coloured pixels of CL undergoing luteolysis (0.38 ± 0.012 mm2 and 0.31 ± 0.017 mm2, respectively, P < 0.001). Assessment of day-based examination showed a significant difference between the area of coloured pixels of CL with continuing pregnancy and luteolysis on Day 17 (P < 0.05), which was followed by Days 18 and 19 (P < 0.001). It is concluded that pregnancy diagnosis can be done accurately by semiquantitative assessment of luteal vascularization as early as 17 days post breeding in ewes. According to the authors’ knowledge, this is the first report on the efficacy of semiquantitative assessment of ovine CL in early pregnancy diagnosis.

Initialization of active contours for segmentation of breast cancer via fusion of ultrasound, Doppler, and elasticity images

Active contours (snakes) are an efficient method for segmentation of ultrasound (US) images of breast cancer. However, the method produces inaccurate results if the seeds are initialized improperly (far from the true boundaries and close to the false boundaries). Therefore, we propose a novel initialization method based on the fusion of a conventional US image with elasticity and Doppler images. The proposed fusion method (FM) has been tested against four state-of-the-art initialization methods on 90 ultrasound images from a database collected by the Thammasat University Hospital of Thailand. The ground truth was hand-drawn by three leading radiologists of the hospital. The reference methods are: center of divergence (CoD), force field segmentation (FFS), Poisson Inverse Gradient Vector Flow (PIG), and quasi-automated initialization (QAI). A variety of numerical tests proves the advantages of the FM. For the raw US images, the percentage of correctly initialized contours is: FM-94.2%, CoD-0%, FFS-0%, PIG-26.7%, QAI-42.2%. The percentage of correctly segmented tumors is FM-84.4%, CoD-0%, FFS-0%, PIG-16.67%, QAI-22.44%. For reduced field of view US images, the percentage of correctly initialized contours is: FM-94.2%, CoD-0%, FFS-0%, PIG-65.6%, QAI-67.8%. The correctly segmented tumors are FM-88.9%, CoD-0%, FFS-0%, PIG-48.9%, QAI-44.5%. The accuracy, in terms of the average Hausdorff distance, is respectively 2.29 pixels, 33.81, 34.71, 7.7, and 8.4, whereas in terms of the Jaccard index, it is 0.9, 0.18, 0.19, 0.63, and 0.48.

Use of contrast-enhanced ultrasonographic examination to evaluate health status of mammary glands of ewes at the end of a lactation period

This research communication describes the use of contrast-enhanced ultrasonographic examination (CEUS) in mammary glands of ewes for diagnosis of chronic mastitis; this is the first report of the use of this modality in diagnostic imaging of mammary glands of ruminants. For this purpose, a convex transducer was used, with the following settings: frequency: 2·0/4·0 MHz, mechanical index: 0·09, power: 22 dB, scanning depth: 70 mm, and sulphur hexafluoride in microbubbles at a dose of 20 µl as the contrast agent. In four healthy mammary glands (2 ewes), CEUS examination revealed a steady biphasic pattern of contrast agent kinetics characterised by initial uptake within 15–40 s post-injection, at which time intensity peaked with strong enhancement (130–200 AEU) followed by a gradual wash-out phase. In three mammary glands with history of clinical mastitis (2 ewes), the pattern was particularly inconsistent and unclear, with weak enhancement (<100 AEU) (P < 0·01) lasting for a short period. Notwithstanding issues regarding cost and withdrawal period of contrast-agent, this imaging modality may contribute to improved diagnosis of mastitis cases, especially on occasions when abnormalities cannot be easily confirmed by more conventional methods.