77 



date, there has been no study documenting the health history of a group of dolphins 

 with frequent casual contact with the human public. The dolphins at the Dolphin 

 Quest facility at the Hyatt Regency Waikoloa on the Big Island of Hawaii are in- 

 volved in one of four SwTD programs which operate under a special pennit from 

 the National Marine Fisheries Service, and for these animals, the program of pre- 

 ventive veterinary care includes the maintenance of extensive health history prac- 

 tices and records. 



To address this subject, a retrospective study of Dolphin Quest medical records 

 was undertaken. The preventive health care program at Dolphin Quest actively in- 

 corporates medical behaviors into the health assessment process. Trained medical 

 behaviors have become an ever more prominent aspect of health care programs for 

 marine mammals. The collection of sputum exudates from dolphins and whales by 

 training them to exhale forcefully on presentation of a signal, is one of the easiest 

 to train and one which yields an abundance of information about the state of the 

 respiratory tract. Specifically for assessment of inflammation in the respiratory 

 tract, cytoiogical analysis of sputum exudates provide an ideal opportunity to iden- 

 tify the cellular components associated with inflammation, the leukocytes, or white 

 blood bells. These cells, one of the body's defensive mechanisms, are attracted to foci 

 of invasion and tissue insult and therefore appear, beginning early in the reactive 

 process, within exudative materials derived from that foci. By performing these sim- 

 ple procedures on each dolphin on a frequent and regular basis, an ongoing record 

 of the health status of organ systems, e.g., the respiratory tract, for each animal can 

 be documented. 



MATERIALS AND METHODS 



The cytoiogical examination of respiratory sputum is ideally suited to dolphins, 

 as they can easily be trained to blow or cough with force into a collection container 

 or culture plate. 



In so domg, they liberate a representative sample of the cellular contents of the 

 lungs, bronchi, nares and cranial sinuses. These contents are immediately visualized 

 through routine microscopic examination, and quantitatively recorded. A ratio of 

 white blood cells to epithelial cells (normal cells which line the membranes of the 

 respiratory tract) provides the ability of noting changes in the tract, particularly the 

 onset of subclinical (early cellular reactivity without physical symptoms) respiratory 

 disease. Any samples having an abnormal ratio can be cultured for micro-organisms 

 (bacteria and/or fungi). 



The microscopic examination of respiratory sputum is accomplished by mixing the 

 sputum material with an equal volume of nuclear chromatin stain, e.g.. New Meth- 

 ylene Blue, and observing under lOX and 40X in the microscope. By this technique, 

 both epithelial cells and white blood cells, as well as numerous other types of cells 

 and micro-organisms, are simple to identify. The observer records the number of 

 these cells identified, and from this exercise, establishes a ratio of white blood cells 

 to epithelial ells. 



RESULTS AND DISCUSSION 



As we humans are all too painfully familiar, respiratory diseases are often charac- 

 terized by prolific production of exudative material. These exudates are full of white 

 blood cells, the ratio of white blood cells to epithelial cells existing commonly at well 

 over 2:1. With clinically apparent respiratory infection in the dolphin (symptoms 

 evident including coughing, audible moist sounds on inspiration or expiration, 

 changes in blood hematology parameters), the clinician would expect to find, as an 

 example, 30 to 40 white mood cells to 5 to 10 epithelial cells, with a ratio factor 

 of 5:1. In the early stages of disease, before symptoms are evident, white blood cells 

 appear in response to the,growing infection and a ratio factor of between 1:1 to 2:1 

 is typical ana suggestive of the presence of a subclinical respiratory inflammation 

 in a dolphin. Such a finding on routine examinations enables the veterinarian to 

 closely monitor the animal, evaluate causes such as parasitism or other non-infec- 

 tious entities, and, if appropriate, institute clinical and possibly pharmacologic re- 

 sponses directed to elimination of the problem before it progresses into clinical dis- 

 ease. This preventive medicine procedure enables us to evaluate our dolphins at a 

 subclinical level, and thus respond unequivocally to this matter with quantitative 

 data. In five years of operation at the Hyatt Regency Waikoloa, there has not been 

 a single occurrence of clinical respiratory symptoms, due to any cause, in any of the 

 six dolphins there. 



Figures 1, 2 and 3 present a retrospective assessment of 334 specimens collected 

 and examined by the procedure described above for all of the Dolphin Quest dol- 

 phins for the last three years, 1991, 1992 and 1993. Note that in only rare instances 



