FETAL OMPHALOCELE IN A COMMON BOTTLENOSE DOLPHIN (TURSIOPS TRUNCATUS)

Abstract

A routine pregnancy ultrasound examination of a 30-yr-old, multiparous, common bottlenose dolphin, Tursiops truncatus, detected an approximately 16-wk (gestational age) fetus with an omphalocele, an abdominal wall defect at the base of the umbilical cord. Throughout the pregnancy, ultrasound allowed for identification of the omphalocele contents, which included a portion of the liver and intestinal loops. The maximum diameter of the omphalocele was 11.4 cm at an estimated 51-wk gestation. Color Doppler was utilized to study the blood flow within the omphalocele as well as diagnose an associated anomaly of the umbilical cord, which contained three vessels instead of four. Gross necropsy and histopathology confirmed the ultrasound diagnoses. This is the first report of an omphalocele in a T. truncatus fetus, and the first report of a fetal and umbilical cord anomaly diagnosed with ultrasound in a cetacean.

Slow recovery of Barataria Bay dolphin health following the Deepwater Horizon oil spill (2013-2014), with evidence of persistent lung disease and impaired stress response

“…Reproductive ultrasound exams, pregnancy confirmation, and due date estimations were performed as previously described (Smith et al 2013, utilizing M-mode and color Doppler interrogation if needed to determine fetal viability. Pulmonary ultrasound exams were performed utilizing the dorsal-ventral slide technique as previously described (Smith et al 2012).…”

Low reproductive success rates of common bottlenose dolphins Tursiops truncatus in the northern Gulf of Mexico following the Deepwater Horizon disaster (2010-2015)

“…Pregnancies were classified as (1) confirmed pregnant: a fetus was detected; (2) probable pregnancy: a corpus luteum (CL) with or without uterine fluid was present in conjunction with a serum progesterone value greater than 5 ng ml −1 ; or (3) confirmed not pregnant: the ovary was seen without a CL, progesterone measurements were less than 5 ng ml −1 and the uterus was visualized without an embryo or fetus (Lane et al 2015). 'Confirmed pregnancies' were given estimated due dates based on fetal biparietal skull diameter (Stone et al 1999, Lacave et al 2004, Smith et al 2013. One sample classified as a 'probable pregnancy' was excluded from the statistical analyses given the unknown level of statistical uncertainty associated with this pregnancy classification (i.e.…”

“…For cetacean species, it has been estimated that progesterone concentrations of pregnant animals rise to levels that are diagnostically distinct from confirmed non-pregnant animals within 3 wk post conception (Kellar et al 2006, Steinman et al 2016. However, unlike with the CRHA ultrasound animals, the endocrine evaluations of the blubber provide no diagnostic information about due date of the pregnant biopsied animals; therefore, the maximum ex pected due date was assumed to be no greater than 13 mo after the biopsy was collected, based on an estimated gestation duration of 12.5 mo, plus 2 wk (O'Brien & , Smith et al 2013.…”

Ultrasonographic findings associated with normal pregnancy and fetal well‐being in the bottlenose dolphin (Tursiops truncatus)

“…Simple and quantile regression analysis was performed to assess the relationship of quantitative variables with the stage of gestation.Pearson correlation coefficient evaluated the relationships between fetal measurements and the day of gestation. Assuming a 380-day gestation in Tursiops,15 fetal age was back-calculated from the parturition date, and trimesters divided into three 127-day blocks (first = 0-126 days, second = 127-253 days, and third = 254-380 days).…”