Reference Intervals for Evaluation of the Gastrointestinal Tract in Clinically Healthy Bottlenose Dolphins (Tursiops truncatus) Under Human Care
Marine mammals, frequently do not show clinical signs of illness early in various disease processes. Preventive medicine of the digestive system in dolphins is fundamental to ensure the welfare of these animals under human care.1 In this study 48 bottlenose dolphins (Tursiops truncatus) hosted in three different facilities (A - B - C) were inspected. Of this group, 31 healthy bottlenose dolphins (Tursiops truncatus), were examined and sampled. All animals were considered clinically healthy based upon a physical exam and laboratory evaluation (complete blood count and serum chemistry, urine analysis, and fecal examination).2 This study aimed to establish: a) provide a detailed description of the ultrasonographic appearance of the normal gastrointestinal region of the bottlenose dolphin in clinically sound individuals; b) defines most useful acoustic windows for the examination of forestomach, fundic stomach, pyloric stomach and bowel; c) defines a consistent and standardized method to measure the entire wall thickness in forestomach, fundic stomach, pyloric stomach, and bowel; d) defines the normal peristalsis of forestomach, fundic stomach, pyloric stomach, and bowel; e) provides reference baseline data for characterising the gastrointestinal tract for healthy animals, based for the first time, on the "Guidelines for the Determination of Reference Intervals in Veterinary Species" issued by the Quality Assurance and Laboratory Standards Committee.3 The ultrasonographic results show that the forestomach wall thickness lower limit is 0.24 cm and the upper limit is 0.80 cm; the fundic stomach wall thickness lower limit is 0.33 cm and the upper limit is 0.71 cm; the fundic stomach ruga lower limit is 1.38 cm and the upper limit is 2.56 cm; the fundic stomach inter-ruga lower limit is 0.73 cm and the upper limit is 1.84 cm; the pyloric chamber wall thickness lower limit is 0.09 cm and the upper limit is 0.63 cm; the diameter pyloric chamber lower limit is 1.74 cm and the upper limit is 3.3 cm; the bowel wall thickness lower limit is 0.31 cm and the upper limit is 0.71 cm. Ultrasonography plays an important role in modern-day cetacean preventative medicine because it is a non-invasive technique, is safe for both patient and operator, can be performed routinely using medical behaviors, and is also used to follow up on animals undergoing therapy.4 This study expands the present knowledge in bottlenose dolphins, providing additional relevant data and allowing the clinician the possibility to evaluate gastric health more extensively.
We would like to thank Zoomarine Italy, Zoomarine Portugal, and Oceanografic of Valencia for their support to this project. We are especially grateful to all the staff of veterinarians and trainers who dedicate themselves daily to dolphin welfare.
* Presenting author
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3. Friedrichs KR, Harr KE, Freeman KP, Szladovits B, Walton RM, Barnhart KF, Blanco-Chavez J. ASVCP reference interval guidelines: determination of de novo reference intervals in veterinary species and other related topics. Veterinary Clinical Pathology. 2012;41(4):441–453.
4. Saviano P. Handbook of Ultrasonography in Dolphins: Abdomen, Thorax and Eye. 2013. E-book available from Amazon.com.