#Dolphin fetus serial#

Ten dolphins were evaluated at the US Navy Marine Mammal Program in San Diego, California and two at Dolphin Adventure in Puerto Vallarta, Mexico. They were considered in good health by licensed clinical marine mammal veterinarians based on routine blood work, ultrasonography, and absence of clinical signs throughout pregnancy. Dams ranged in age from 9 to 46 years old at parturition. Reproductive success was defined as delivery of a calf that survived ≥30 days.

#Dolphin fetus serial#

In this prospective, longitudinal cohort study, serial voluntary transabdominal ultrasonography was performed on 12 healthy pregnant dolphins during the course of 16 successful pregnancies. 2 MATERIALS AND METHODS 2.1 Study population 32, 33 The purpose of this study was to expand upon early work in gestational ultrasound of bottlenose dolphins 34- 36 and develop a reproducible protocol for ultrasonographic monitoring of fetomaternal health in the bottlenose dolphin, reporting normal measurements and descriptive findings correlating with a positive outcome. 29- 31 As dolphins and horses have a similar diffuse epitheliochorial placenta, equine reproductive ultrasound provides a reasonable species model. 25- 28 Such evaluations help predict positive versus negative outcomes and aid in understanding of pregnancy failure pathophysiology. Standard ultrasonographic methodology to assess fetal growth and well-being has been established in humans and horses. 23, 24 To better understand these findings, promptly diagnose congenital anomalies, and enhance early detection of pregnancy complications in wild and managed dolphins, there is a need for more sophisticated assessments of fetoplacental health.

20- 22 The most likely cause of these abnormalities was exposure to petroleum products. 18 Following the “Deepwater Horizon” oil spill in 2010, wild dolphins living in oil-impacted bays had increased prevalence of perinatal mortality, fetal distress, fetal pneumonia, 19 and maternal pulmonary disease and reproductive failure. 14Ī number of congenital lesions have been reported in Tursiops fetuses and perinates, including umbilical cord abnormalities, 15, 16 vascular pathologies, 17 and cranial malformations. 10- 13 This knowledge has successfully been applied to longitudinal investigations of wild dolphin health. 3- 9 Improved understanding of Tursiops reproduction through routine imaging in managed care has led to advancements in hormone analysis, gonadal evaluation, early fetal monitoring, parturition prediction, and artificial insemination. 2 Ultrasound is also a critical component of bottlenose dolphin ( Tursiops truncatus) medicine and has been used to evaluate pulmonary, cardiac, reproductive, hepatic, urinary, gastrointestinal, and lymphatic systems. Advances in human perinatology and maternal-fetal medicine have been shown to reduce morbidity and mortality, 1 and fetomaternal ultrasound is vital in monitoring pregnancy and maximizing neonatal survival. Ultrasonographic evaluation of pregnancy is a valuable non-invasive diagnostic tool, well-established in human and veterinary medicine. Future applications of these normal data will help identify in utero abnormalities indicative of fetal morbidity, and improve understanding of reproductive failure in wild and managed populations. Ultrasonographic characteristics of normal pregnancy in dolphins are described and an equation for prediction of parturition date in Tursiops is reported: days to parturition = 348.16 − (26.03 × BPD(cm)) ( R 2 = 0.99). Regional uteroplacental thickness significantly increased with each trimester (range 0.22–0.40 cm P < .00011 cranial uterus, P < .00057 mid, and P < .000011 caudal). Fetal biparietal diameter (BPD), thoracic width in dorsal and transverse planes, thoracic height in a sagittal plane, aortic diameter, and blubber thickness all demonstrated high correlation with gestational age ( r > 0.94, P < .00001). Several metrics were accurate in predicting fetal age. A total of 203 ultrasound examinations were included in the study. From 2010 to 2017, serial ultrasonographic evaluations of 12 healthy dolphins were performed over the course of 16 pregnancies.

The purpose of this prospective longitudinal cohort study was to develop a protocol for fetomaternal ultrasonographic monitoring in dolphins and to report normal measurements and descriptive findings correlated with a positive outcome. Ultrasonography is an invaluable, non-invasive tool in assessing the fetomaternal unit in humans and animals, including dolphins and horses. Reproductive success is vital in sustaining free-ranging and managed bottlenose dolphin ( Tursiops truncatus) populations.