Chorionic Cavity Diameter Research Articles

Evaluation of embryo-foetal biometry and its correlation with parturition date in Toy Poodle bitches.

Estimating the parturition date in dogs is challenging due to their reproductive peculiarities that. Ultrasonographic examination serves as a tool for studying embryo/foetal biometry and estimating the time of parturition by measuring foetal and extra-foetal structures. However, due to reproductive differences among various dog breeds, such estimates may have a non-significant pattern, representing inaccuracies in the estimated date of birth. This study aimed to monitor pregnant Toy Poodle bitches and establish relationships between ultrasonographically measured foetal and extra-foetal dimensions and the remaining time until parturition. Eighteen pregnant Toy Poodle bitches were subjected to weekly ultrasonographic evaluations and measurements of the inner chorionic cavity diameter, craniocaudal length (CCL), biparietal diameter (BPD), diameter of the deep portion of diencephalo-telencephalic vesicle (DPTV), abdominal diameter, thorax diameter (TXD), placental thickness and the renal diameter (REND). These parameters were retrospectively correlated with the date of parturition and linear regressions were established between gestational measurements and days before parturition (DBP). All analyses were conducted using the Statistical Package for Social Sciences (IBM® SPSS®) program at a 5% significance level. The foetal measurements that showed a high correlation (r) and reliability (R2) with DBP were BPD [(DBP = [15.538 × BPD] - 39.756), r = .97 and R2 = .93], TXD [(DBP = [8.933 × TXD] - 32.487), r = .94 and R2 = .89], DPTV [(DBP = [34.580 × DPTV] - 39.403), r = .93 and R2 = .86] and REND [(DBP = [13.735 × REND] - 28.937), r = .91 and R2 = .82]. This statistically validates the application of these specific formulas to estimate the parturition date in Toy Poodle bitches.

Comparative evaluation of three different formulas for predicting the parturition date of German Shepherds following somatic cell nuclear transfer.

Several studies have reported methods to estimate the parturition date of dogs using ultrasonographic measurements. However, these prediction models were mainly determined using ultrasonographic measurements of naturally pregnant small- and medium-sized dogs, and no such studies have been performed using dogs carrying cloned fetuses produced via somatic cell nuclear transfer. The present study evaluated the abilities of three reference formulas (Luvoni and Grioni, Milani et al., and Groppetti et al.), all of which were developed using data from naturally occurring pregnancies, to accurately predict the parturition date in surrogates carrying cloned German Shepherd (GS) fetuses. All three formulas were based on the use of inner chorionic cavity diameter (ICC) measurements, obtained via ultrasonography. For evaluation, a total of 54 ICC measurements were collected from 14 pregnant bitches carrying cloned GS fetuses. We found that the clinical accuracy of the breed-specific Groppetti et al. formula was highest among those of the three formulas tested, with 87% and 100% of the estimated parturition dates (calculated based on the ICC measurements) being within 1 and 2 days, respectively, of the actual delivery date. By contrast, the Luvoni and Grioni formula showed relatively low accuracy, and the Milani et al. formula showed higher accuracy than that reported previously for natural pregnancies.

Possibilities of using ultrasonographic fetal biometry in cats

Ultrasonographic fetal biometry is a technique used in both human and veterinary medicine to predict parturition time and evaluate fetal development. In domestic cats, the parameters that have been examined so far are the inner chorionic cavity diameter (ICC), biparietal diameter (BPD), deep portion of diencephalotelencephalic vesicle (DPTV), femur length (FL), body diameter/abdominal diameter (BD/AD), and eye diameter (ED). The most accurate are ICC and BPD measured in early and late pregnancies. With regard to breed and size differences, there are formulas dedicated to Maine coons. There is a need to develop formulas for other domestic cat breeds and to examine the course of development of more fetal structures.

Determination of delivery in bitches through ultrasound measurement of fetal and extrafetal structures

The aim of this study was to evaluate the use of ultrasound as a method of gestational diagnosis in female dogs, and its use in monitoring fetal development and viability, in determining gestational age and probable date of delivery in female dogs. The canine gestation time is relatively short, resulting in the development of the main fetal organs in their final period, and birth of immature fetuses. Determining gestational age allows the time of birth to be estimated, so that breeders and veterinarians can help reduce peripartum loss. Ultrasound measurement of extra-fetal and fetal structures is a common and accurate method for predicting the date of delivery during canine pregnancy, in which they will be chosen depending on the gestational period of the female. The inner chorionic cavity diameter (ICC) is considered the most accurate indicator of gestational age between the 20th and 37th days, whereas biparietal diameter (BPD) is a reliable parameter in the final third of pregnancy, between the 38th and 60th days. Breed variations in dogs may interfere in gestational age calculations based on fetal measurements, and it is necessary to establish measurement standards and calculations for animals of the same size or breed characteristics.

Specific fetometric formulas of ICC and BP for calculating the parturition date in the miniature breeds of canine.

The aim of this study was to derive the growth curves of the inner chorionic cavity and the biparietal distance in miniature dog breeds by ultrasonographic fetometry and present new specific formulas for prediction of parturition date. In this study, foetal biometry parameters were obtained using serial ultrasonographic examinations in 24 pregnant bitches of six different miniature breeds (≤5kg). The mating time was unknown. Overall, 25 inner chorionic cavity diameter (ICC) and 22 biparietal diameter (BP) measurements were taken. The relationship between ICC or BP growth and days to parturition was analysed by linear regression. The results showed a significant relationship between days before delivery and ICC or BP. The equations derived from the growth curves can be used in practical prediction of parturition date in miniature dog breeds.

Comparison of three different fetometric formulas of ICC and BP for calculating the parturition date in a population of German Shepherd

The aim of this study was to evaluate the suitability of three different formulas to predict the parturition date in German Shepherds, using the ultrasonographic fetometry method involving inner chorionic cavity diameter (ICC) and biparietal diameter (BP) measurements in the same population of a single breed. Overall, 53 ICC and 42 BP measurements were taken on 34 bitches. The measured values were substituted into breed-specific formulas for the German Shepherd as well as non-specific formulas for medium-sized bitches. Comparisons of clinical accuracy and statistical analyses of regression lines were performed to test the compatibility of the formulas used. We confirmed the similarity of our clinical results to outcomes obtained using the one breed–specific (Groppetti et al. 2015) and non–specific fetometry models (Luvoni and Grioni 2000), whereas another breed–specific formula (Milani et al. 2013) showed rather low accuracy. Comparing the clinical accuracy of the three formulas, the authors demonstrated that the Luvoni and Grioni (2000) formula for ICC dedicated to medium-sized dogs can also be effectively used in the German Shepherd, even with better results than breed-specific formulas by Groppetti et al. (2015). By contrast, the evaluation of BP formulas proves the successful usage of the Groppetti et al. (2015) formula to determine the date of birth by measuring scull bone structures (p < 0.05). The statistical analysis of regression lines were in agreement with the clinical results and confirmed the higher predictability of Groppetti et al. (2015) and Luvoni and Grioni (2000) formulas, than those of Milani et al. (2013).

Ultrasonographic fetometry formulas of inner chorionic cavity diameter and biparietal diameter for medium-sized dogs can be used in giant breeds

The aim of this study was to evaluate the suitability of the ultrasonographic fetometry method, involving inner chorionic cavity diameter (ICC) and biparietal diameter (BP) measurements, to predict the parturition date in giant breed dogs. Overall, 30 ICC and 24 BP measurements were taken on 24 giant breed bitches. The measured values were substituted into Luvoni and Grioni (2000) formulas for medium-sized bitches because formulas with ICC and BP to dogs with a body mass greater than 40 kg have not been defined. The accuracy of the parturition date predictions proved the method to be highly useful in the observed group of dogs. Prediction accuracy in the giants ranged between 54.16% (±1 day, using BP) and 90% (±2 days, using ICC), depending on the parameter measured and precision levels used. Numerically, the results obtained using ICC were better; however, no statistically significant differences between ICC and BP accuracy were found when comparing the effectiveness of the parturition date predictions. Regression lines based on the own fetometric measurements were highly convergent with the lines defined by Luvoni and Grioni (2000) formulas for medium-sized bitches. This outcome suggests a similar gestational development of fetuses in giant dogs and the possible use of Luvoni and Grioni (2000) formulas for medium-sized dogs with breeds weighing greater than 40 kg.

Breed-specific fetal biometry and factors affecting the prediction of whelping date in the German shepherd dog

To date many studies have been published about predicting parturition by ultrasonographic fetal measurements in the bitch. Given that accuracy in such prediction is a key point for clinicians and breeders, formulas to calculate the whelping date were mainly obtained from small and medium sized dogs, which means poor accuracy when applied to large or giant breeds.Based on the evidence that ethnicity significantly affects fetal biometry in humans, this study aimed at developing a breed-specific linear regression model for estimating parturition date in the German shepherd dog. For this purpose, serial ultrasonographic measurements of the inner chorionic cavity diameter (ICC) and the fetal biparietal diameter (BP) were collected in 40 pregnant German shepherd bitches. The quality of the regression models for estimating parturition date was further verified in 22 other pregnant German shepherd bitches. Accuracy related to the prediction of parturition date was higher than previously reported: 94.5% and 91.7% within ±2 days interval based on ICC and BP measurements, respectively. Additional investigation was performed on the effects of maternal weight, age and litter size in relation to fetal biometry and to accuracy of parturition estimation. Moreover, the study included a comparison between hormonal and fetal ultrasound (ICC and BP) measurements connected to the estimation of whelping date.We suggest that specific equations from a single breed are likely to offer excellent accuracy, comparable to that of periovulatory progesteronemia, in parturition prediction and to avoid morphological variables present in dogs of different breeds even with the same size/weight.

Predicting the Parturition Date in Bitches of Different Body Weight by Ultrasonographic Measurements of Inner Chorionic Cavity Diameter and Biparietal Diameter.

Predicting the parturition date in dogs by taking ultrasonographic foetometry has opened interesting research areas of veterinary obstetrics. Recently developed calculation formulas of inner chorionic cavity diameter (ICC) and biparietal diameter (BP) are formulas by Luvoni and Grioni (2000). This study is one of the first reports referring to ICC and BP with the use of Luvoni and Grioni formulas for predicting the parturition time in dogs of different body weight in clinical practice conditions. The research material consists of 70 clinically healthy pregnant bitches of 27 breeds and cross-breeds. Bitches were divided into 4 groups according to their body weight. In each of the bitches, ultrasonographic examination of pregnancy was performed at least twice (ICC and BP measurements). Parturition dates for dogs with a body weight over 25 kg were calculated based on formulas intended for the group of medium dogs. It was caused by the lack of appropriate formulas for these groups of dogs. The predicting parturition dates were compared with the actual dates of delivery provided by the bitch owners. Generally, the results obtained in this study are very encouraging and similar or even better than those published by other authors using foetometric measurements. In our research, when comparing the effectiveness of predicting the delivery date based on foetometric formulas by Luvoni and Grioni (2000), it was proved that in all groups of dogs, even those over 25 kg, ICC and BP measurements at both accuracy levels were characterized similar reliability.

Effectiveness of determining the parturition date in bitches using the ultrasonographic fetometry as compared to hormonal and cytological methods

In clinical practice, the parturition date in bitches is calculated on the basis of the established ovulation date, using determination of the level of LH and P4. Additionally cytological examination of vaginal smears makes it possible to establish the onset of diestrus, from which the delivery occurs after about 57 days. The latest method used in bitches for this purpose is foetal biometry. Measurements of the inner chorionic cavity diameter (ICC) and biparietal diameter (BP) with formulas published by Luvoni and Grioni have been popularized and the most practically useful. In a group of six bitches the effectiveness obtained with the use of ICC was 66.67% with an accuracy of 1 day and 100% with an accuracy of 2 days. BP measurements gave better results, as the accuracy was respectively 83.33% and 100%. The effectiveness of predicting the delivery date on the base of method consisting in determining the LH surge was 66.67% with an accuracy of 1 day and 100% with an accuracy of 2 days. The best effectiveness was obtained while using the method based on P4 level determination (100% both with an accuracy of 1 day, as well as of 2 days). The lowest accuracy was obtained while using the cytological method. Generally, a comparison of the methods used for predicting the date of delivery in bitches confirms practical usefulness of fetometry. Its effectiveness was not lower than traditional methods used so far, while its advantage lies in the ease of performance and the long term of application during gestation. However, full confirmation of the practical usefulness of this method requires further research on a larger number of animals.

A one-foetus pregnancy monitored by ultrasonography and progesterone blood levels in a German Shepherd bitch: a case report

This case study describes the pregnancy of a German Shepherd bitch with a singleton (one puppy) litter as a result of early embryo resorption. Resorption was confirmed by ultrasonography and the pregnancy was regularly monitored by USG and measurements of progesterone levels until parturition. These levels stayed within the physiological range. One healthy puppy was delivered within the timeframe of a physiological pregnancy although the inner chorionic cavity diameter (ICCD) protocol used for predicting the time of parturition showed divergence from the real time of whelping.

Comparison of the accuracy of two ultrasonographic measurements in predicting the parturition date in the bitch

To compare the accuracy of two ultrasonographic measurements, inner chorionic cavity diameter and biparietal diameter, for the prediction of parturition date in small and medium size bitches. The effects of litter size and fetal sex ratio on the accuracy of the prediction were also investigated. Ultrasonographic examinations were performed on pregnant bitches and, depending on the stage of pregnancy, the inner chorionic cavity diameter and biparietal diameter were measured. The mean value of the data of each structure was calculated and the predicted day of parturition was obtained by the application of equations derived from growth curves we previously developed for different size bitches. The parturition term was predicted with similar accuracy during early gestation, by the measurement of inner chorionic cavity diameter, as well as during late gestation, by the measurement of biparietal diameter. Litter size affected only biparietal diameter accuracy, whereas fetal sex ratio did not influence the estimation of the day of parturition. Inner chorionic cavity diameter and biparietal diameter were equally reliable parameters in obtaining a reasonably accurate prediction of parturition date at any gestational period at which a bitch is examined.

MSP003 Presence of multi-drug efflux pump gene adeB in clinical isolates of Acinetobacter baumannii

To date many studies have been published about predicting parturition by ultrasonographic fetal measurements in the bitch. Given that accuracy in such prediction is a key point for clinicians and breeders, formulas to calculate the whelping date were mainly obtained from small and medium sized dogs, which means poor accuracy when applied to large or giant breeds.Based on the evidence that ethnicity significantly affects fetal biometry in humans, this study aimed at developing a breed-specific linear regression model for estimating parturition date in the German shepherd dog. For this purpose, serial ultrasonographic measurements of the inner chorionic cavity diameter (ICC) and the fetal biparietal diameter (BP) were collected in 40 pregnant German shepherd bitches. The quality of the regression models for estimating parturition date was further verified in 22 other pregnant German shepherd bitches. Accuracy related to the prediction of parturition date was higher than previously reported: 94.5% and 91.7% within ±2 days interval based on ICC and BP measurements, respectively. Additional investigation was performed on the effects of maternal weight, age and litter size in relation to fetal biometry and to accuracy of parturition estimation. Moreover, the study included a comparison between hormonal and fetal ultrasound (ICC and BP) measurements connected to the estimation of whelping date.We suggest that specific equations from a single breed are likely to offer excellent accuracy, comparable to that of periovulatory progesteronemia, in parturition prediction and to avoid morphological variables present in dogs of different breeds even with the same size/weight.

Establishment of the prediction table of parturition day with ultrasonography in small pet dogs.

To establish a prediction table of parturition day the real-time B-mode ultrasonographic examinations were performed in the 8 pregnant Malteses and 10 Yorkshire terriers (total pups, 25 and 38 pups, respectively) from 18 days of gestation until the parturition. Ovulation was designated the first day of gestation (day 0). Extra fetal and fetal structures were measured from all conceptues. The parameters that exhibited the best correlation to parturition were used to compile a prediction table of parturition day. To testify the precision of the prediction table of parturition day, the 15 pregnant Malteses (48 pups) and 13 pregnant Yorkshire terriers (42 pups) with unknown mating time were examined using ultrasonography. Inner chorionic cavity diameter on days 18 to 37 and fetal head diameter on day 38 to parturition that showed the best correlation to gestational age were the most pertinent to the estimation of gestational age and the prediction of parturition day. The two parameters were used to compile a prediction table of parturition with averaged regression equations. In verificational examinations, with the exception of I Yorkshire terrier (3.6%) having 1 fetus, 18 of 28 bitches (64.3%) delivered exactly on the date predicted and 9 of 28 bitches (32.1%) delivered within I day of the date predicted. Therefore, the prediction table of parturition day seems to be a useful tool of the prediction of parturition day in practice.

The growth of the human embryo. A longitudinal biometric assessment from 7 to 12 weeks of gestation.

Longitudinal studies of multiple parameters in the first trimester for assessment of embryonic growth are lacking. This study's aim was to register changes in growth over time, by taking several measurements of embryos on successive occasions and evaluating these changes by longitudinal analysis. This prospective longitudinal study describes the normal embryonic growth in vivo. Inclusion criteria were non-smoking women with single uneventful pregnancies, regular menstrual periods (28-30 days) and no hormone therapy in the 3 months prior to the pregnancy. Exclusion criteria were pregnancy complications such as diabetes, pre-eclampsia, delivery of preterm or growth-restricted infants. Of 36 recruited pregnant women, 29 met these criteria. Each pregnancy was examined five times between 7 and 12 weeks of gestation. This resulted in a two-level data set, where level 1 consisted of the observations and level 2 consisted of the individuals. The longitudinal data were analyzed with a software package specially created for multilevel analysis. The growth of the biparietal diameter (BPD), occipitofrontal diameter (OFD), mean abdominal diameter (MAD), chorionic cavity diameter and amniotic cavity diameter was constant; the growth of the crown-rump length (CRL) and the yolk sac diameter was not constant. Variation in the data sets was mainly caused by variation between the embryos/fetuses. The measured parameters except for the yolk sac showed a high degree of uniformity with virtually the same growth velocities. The yolk sac demonstrated uniform growth until week 10 only. Differences between the gestational age based on the last menstrual period and the true gestational age, and/or differences in the early growth of the embryos before the start of the study at 7 weeks, may have contributed to the variation between the individuals.

Ultrasonographic appearance of the uterus, placenta, fetus, and fetal membranes throughout accurately timed pregnancy in Beagles

Summary Serial ultrasonographic examinations were performed on 8 Beagle bitches from 20 to 60 days pregnant to determine time of first detection, appearance, and sizes of selected features of pregnancy. Gestation was timed from the day of the preovulatory luteinizing hormone surge. Findings related to gestational age were consistent among bitches. Gestational ages at earliest detection of the following features were: chorionic cavity at day 20; placental layers in the uterine wall at day 22 to 24; zonary placenta at day 27 to 30; embryo and heartbeat at day 23 to 25; yolk sac membrane at day 25 to 28; allantoic membrane at day 27 to 31; choroid plexus of the brain at day 31 to 35; fetal movement at day 34 to 36; skeleton at day 33 to 39; bladder and stomach at day 35 to 39; kidney at day 39 to 47; and liver hypoechoic, compared with lung, at day 38 to 42. Extra-fetal structures were measurable from day 20 or 22 through day 48. Chorionic cavity diameter increased from 0.2 ± 0.0 cm to 3.3 ± 0.2 cm, outer uterine diameter increased from 0.8 ± 0.03 cm to 4.8 ± 0.2 cm, length of chorionic cavity or zonary placenta increased from 0.3 ± 0.03 cm to 4.9 ± 0.05 cm, uterine wall thickness increased from 0.3 ± 0.03 cm to 0.8 ± 0.01 cm, and placental thickness increased from 0.1 ± 0.0 cm to 0.5 ± 0.05 cm. Chorionic cavity diameter, outer uterine diameter, and placental length each increased at a linear rate through day 37, after which time, each had a marked plateau in growth. Of the extra-fetal structures, chorionic cavity diameter was the most accurate for estimation of gestational age. All of the fetal structures studied increased at an increasing (second order) rate. Crown-rump length increased from 0.3 ± 0.05 cm on day 24 to 9.2 ± 0.2 cm on day 48. Body diameter increased from 0.2 ± 0.03 cm on day 24 to 4.6 ± 0.15 cm on day 60. Head diameter increased from 0.8 ± 0.05 cm on day 34 to 2.7 ± 0.04 cm on day 60. Of the fetal structures, head diameter was the most accurate for estimation of gestational age.

Diagnosis of viability in early pregnancy with vaginal sonography.

The detection rate of embryonic heart action using vaginal sonography was evaluated in 363 normal singleton pregnancies in the first trimester. Visible cardiac activity was present at the earliest at a gestational age of 40 days; in addition, the smallest chorionic cavity had a mean diameter of 9.3 mm, the lowest human chorionic gonadotropin (beta-hCG) concentration (calibrated against the first international reference preparation) measured 6,770 mIU/mL, the thinnest trophoblast was 1 mm, and the shortest crown-rump length was 2 mm. Cardiac pulsations were identified in all cases either at a menstrual age greater than or equal to 46 days, a beta-hCG greater than or equal to 47,171 mIU/mL, a mean chorionic cavity diameter greater than or equal to 18.3 mm, or a trophoblast thickness greater than or equal to 5 mm. The heart rate (mean +/- SD) increased from 110 +/- 8 beats per minute (bpm) at 5 weeks menstrual age to 170 +/- 6 bpm at 9 weeks and declined thereafter to 159 +/- 3 bpm at 13 weeks. Vaginal sonography enables a rapid and reliable assessment of embryonic life in early pregnancy.

The embryonal yolk sac in disordered early pregnancy

The detection rate and size of the yolk sac were evaluated by means of vaginal sonography in a prospective study in 377 singleton pregnancies. 298 were normal pregnancies and 79 were spontaneous abortions, the latter of which were viable in 18 cases at the time of examination and non-viable in 61 cases. With a reliable gestational age between 5 and 10 weeks, the yolk sac was recognized in 158 of 172 normal pregnancies (91.9%), in all 14 viable but later aborted pregnancies, but only in 10 of 29 non-viable pregnancies (34.5%) (p less than 0.0000005). With a mean diameter of the chorionic cavity between 5 and 50 mm, the yolk sac was identified in 237 of 253 normal gestations (93.7%), in 16 of 18 viable but later aborted gestations (88.9%), but only in 14 of 41 non-viable gestations (34.1%) (p less than 0.0000001). A diameter of the yolk sac above 6 mm was observed in 5 of 253 normal pregnancies (2.0%), but in 7 of 29 spontaneous abortions (24.1%) (p less than 0.00005). A diameter above 7 mm was not seen in any instance of normal development but in 4 of the pathological courses (13.8%) (p less than 0.0001). It is concluded, that a yolk sac which is not visible in vaginal sonography between 5 and 10 complete weeks menstrual age or a chorionic cavity diameter between 5 and 50 mm and a yolk sac diameter above 6 mm can serve as indicators of a developmental disturbance in early pregnancy.