ABSTRACT
Cytology, the microscopic study of cells, is a readily available inexpensive diagnostic tool and a valuable part of a preventive medical program. Similar to most nondomestic animals, marine mammals often mask early signs of poor health. However, disease processes often produce cytological abnormalities that, if examined, can indicate illness before the onset of obvious clinical signs (Cowell et al., 1999). Cytology may also be useful in monitoring the progress of a pathological process. Jergens et al. (1998) found a high correlation between the results of cytological and histological examination of samples collected by endoscopy of the stomach, small intestine, and colon of cats and dogs. Cytology in marine mammals is a developing field, with most samples examined to date having been taken from cetaceans rather than pinnipeds (Campbell, 1999).
