On the Dissection of a Female Asian Elephant (Elephas maximus maxiums Linnaeus, 1758) and Data from Other Elephants
A 46-year old female Asian elephant (Elephas maximus maximus Linnaeus, 1758), named "Iki," died on July 8, 1980, at the Ringling Brothers and Barnum & Bailey Circus, Circus World, Haines City, Florida, USA. She was transported to Detroit and was dissected by the Elephant Interest Group (EIG) and friends, Department of Biological Sciences, Wayne State University. The purpose of this continuing study has been to collect data supplemental to that of previous workers, and to enrich knowledge of elephant anatomy, particularly in areas not thoroughly investigated in the past. Some of these findings were compared to those observed in other elephants: "Shirley", "Tulsa", and "Toose" and to the organs of "Ole Diamond" and "Hazel" (see Appendix II). Measurements and weights were taken and samples were collected, including 218 skin samples for histological studies. Most of the observations, not only on Iki but also on other elephants, correlate with those of previous workers. To our knowledge, some of the data collected on Elephas maximus in these dissections have not appeared in literature. Following is a list of the new anatomical and pathological findings: 1. The presence of the trachea-oesophageal muscle was noted in one (Shirley) of the four elephants examined (Iki, Shirley, Tulsa and Ole Diamond); this muscle was identified under the microscope as a striated or voluntary muscle. The trachea-oesophageal muscle was described by Harrison (1850a). Watson (1872a) and Miall and Greenwood (1878) searched for this muscle unsuccessfully. 2. The intercommunicating canals uniting the right and left nasal passages of the trunk and the associated fibrous arches were absent in Iki and Tulsa, the only two elephants examined for this structure. These arches and canals were described by Anthony and Coupin (1925). 3. The volume of the nasal passages of the embalmed trunk of Iki when filled with water was 2.19 liters, and the computed volume of the trunk of Tulsa (computed from measurements at cross sections soon after death) was 3.08 liters. These measurements were compared to the trunk water-holding capacity of three live elephants, large, medium, and small whose maximum capacities were 10.47, 4.18, and 3.57 liters, respectively (Appendix V). 4. The dry weights of the eye lenses of Iki, Shirley, Tulsa, and Toose were measured. Data obtained so far indicate that the older the elephant the heavier its eye lens is (Table VI). The dry weights of the eye lenses of known-aged Asian elephants will be used to construct a growth curve similar to the curve constructed for the African elephant (Laws, 1967). 5. The percentages of dressed (skinned) forelegs weights to the total body weights of Iki and Tulsa were 5.72% and 4.43%, respectively. 6. The percentages of dressed hindlegs weights to the total body weights of Iki and Tulsa were 7.28% and 5.66%, respectively. The range for female African elephants as derived by Laws et al. (1967), is 5.3 - 5.8%. 7. The oculomotor nerve originated in Iki's and Tulsa's brains anterior to the caudal cerebral artery. In man, horse, cow, sheep, pig, cat, guinea pig, and chinchilla this nerve originates posterior to the caudal cerebral artery. 8. There were two branches arising from the arch of the aorta in Iki, Shirley and Tulsa, namely, the innominate (brachiocephalic) and the left subclavian arteries. The innominate artery gave rise to the right subclavian and the two carotids, an arrangement found by at least five other workers. Other researchers assert that there are three branches: the right subclavian, a trunk common to the two carotids and the left subclavian. 9. The maximum capacities of the stomach and intestinal tract when filled with water are 76.6 and 616.76 liters, respectively. These figures for the maximum capacity may be different from the true capacity. Our measurements are included for future comparisons. 10. The ratio of the total length of the intestinal tract (small and large intestines and caecum) to the body length, excluding trunk and tail of Iki was 11.69. (An error appears in Elephant, 1(4):45 - it should read "excluding trunk.") Corresponding ratios were calculated for other elephants, see Table V. These ratios were compared to other mammals and found to fall between the ranges of carnivorous, omnivorous and the lower ranges of herbivorous non-ruminant mammals. 11. The wet weight of Iki's skeleton comprised 16.48% of the estimated body weight at death. The total dry weight of bones, 20 months after death, indicated a 39.19% water loss. 12. A small ossified structure (possibly a sesamoid bone) was found at the proximal end and on the posterior side of the humerus between the common tendon of insertion of the teres major and latissimus dorsi, and the humerus. 13. Two small "joint mice" were found in the elbow joint between the humerus and ulna. "Joint mice" are common features of chronic arthritis in humans and animals. 14. Deep grooves were observed on the femuro-tibia and on the humero-ulna and -radius articular surfaces. The two "joint mice" and the deep grooves are believed to be associated with arthritis. 15. Severe endometritis was reported to be the ultimate cause of death. To our knowledge, this is the only reported case of endometritis in elephants. 16. Suggestions and guidelines for further research are included in the CONCLUDING REMARKS. Further examination of Iki's and other elephants' organs and tissues will enhance knowledge of elephant biology and will be useful in comparative studies. This elephant (Iki) was being studied for chronic arthritis (Clark et al., 1980). The pathological findings, especially with respect to the "joint mice" and the grooves on the articular surfaces, which appear to be associated with chronic arthritis, may be of special interest since they occur in humans and in animals large and small. This interest arises because the elephant has a mean life span similar to that of man.
Shoshani, J. (1982). On the Dissection of a Female Asian Elephant (Elephas maximus maxiums Linnaeus, 1758) and Data from Other Elephants. Elephant, 2(1), 3-93. Doi: 10.22237/elephant/1521731887