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PubMed1979

Dislocation of the elbow and its social consequences for an African elephant.

A dislocated elbow of a male elephant calf (Loxodonta africana) in the Addo Elephant National Park resulted in it being harassed by other elephants and consequently leaving its maternal herd at the age of 6 years, rather than the more usual age of 9-10 years. In the absence of large predators the elephant had survived for 9 years and had adapted its locomotion and intraspecific behaviour to its injury. The humeral joint of the affected forelimb was carried in partial extension while the cubital and carpal joints were permanently in partial flexion. Substantial secondary osteoarthritic changes, extensive fusion and compensatory remodelling of the humerus, radius and ulna had taken place together with compensatory development in the musculature. The planes of articulation of the limb bones had also been considerably rotated inward.

Animals↗
PubMed1984

A 1H NMR comparison of the met-cyano complexes of elephant and sperm whale myoglobin. Assignment of labile proton resonances in the heme cavity and determination of the distal glutamine orientation from relaxation data.

The met-cyano complex of elephant myoglobin has been investigated by high field 1H NMR spectroscopy, with special emphasis on the use of exchangeable proton resonances in the heme cavity to obtain structural information on the distal glutamine. Analysis of the distance dependence of relaxation rates and the exchange behavior of the four hyperfine shifted labile proton resonances has led to the assignment of the proximal His-F8 ring and peptide NHs and the His-FG3 ring NH and the distal Gln-E7 amide NH. The similar hyperfine shift patterns for both the apparent heme resonances as well as the labile proton peaks of conserved resonances in elephant and sperm whale met-cyano myoglobins support very similar electronic/molecular structures for their heme cavities. The essentially identical dipolar shifts and dipolar relaxation times for the distal Gln-E7 side chain NH and the distal His-E7 ring NH in sperm whale myoglobin indicate that those labile protons occupy the same geometrical position relative to the iron and heme plane. This geometry is consistent with the distal residue hydrogen bonding to the coordinated ligand. The similar rates and identical mechanisms of exchange with bulk water of the labile protons for the three conserved residues in the elephant and sperm whale heme cavity indicate that the dynamic stability of the proximal side of the heme pocket is unaltered upon the substitution (His----Gln). The much slower exchange rate (by greater than 10(4] of the distal NH in elephant relative to sperm whale myoglobin supports the assignment of the resonance to the intrinsically less labile amide side chain.

Animals↗
PubMed1994

Suspected cardiac glycoside poisoning in elephants (Loxodonta africana).

Two young (< 2 years old) elephants (Loxodonta africana) died suddenly and simultaneously at Ongava Game Reserve bordering on the Etosha National Park, Namibia. Both elephants showed lung congestion, epi- and endocardial haemorrhages and hyperaemic areas in the mucosa of the stomach and small intestine. Histopathology of the myocardium showed multifocal degeneration and necrosis of muscle fibres accompanied by haemorrhages. Parts of the leaves of the alien plant Cryptostegia grandiflora (Asclepiadaceae) were found in the intestinal tracts of the elephants. These findings suggested that the elephants died from heart failure after ingesting this plant which contains cardiac glycosides.

Animals↗
PubMed1995

Characterization of mucus glycoproteins in the intestinal mucosa of the African elephant (Loxodonta africana) following lectin histochemistry.

The glycoproteins of the small intestines, caecum and colon of three adult elephants and one recently weaned elephant calf were examined by means of lectin histochemistry. Tissue sections were histochemically stained with peroxidase-labelled concanavalin A (Con A), asparagus-pea (TPA), peanut (PNA) and wheat-germ (WGA) lectins. Con A and TPA showed no binding activity in the intestinal tract of the adult elephants or the duodenum and ileum of the elephant calf, but did show a small amount of binding activity in the caecum and colon of the calf. WGA bound very intensely throughout the intestinal tracts of the adults and of the calf--especially with the goblet cells located in the crypts of Lieberkuhn and the glands of Brunner--decreasing in intensity towards the luminal surface of the intestinal tract. PNA stained the glands of Brunner of the duodenum faintly and the goblet cells of the ileum moderately, with no staining of the caecum and faint staining of the colon. These results show the distribution of Con A-, WGA-, PNA- and TPA-binding sites, and the changes that take place in the type of glycoprotein secreted after a change in the diet of the animal.

Animals↗
PubMed1995

Epidemiology of African horsesickness: antibodies in free-living elephants (Loxodonta africans) and their response to experimental infection.

The presence of low levels of group- and type-specific antibodies against African horsesickness virus in the serum of some free-living elephants was reconfirmed. Experimental infection resulted in conflicting results. No detectable viraemia nor virus could be demonstrated in the organs of the six elephant calves and none of them mounted significant levels of neutralizing antibodies against the virus. On the other hand, all calves showed a slight rise in ELISA titres. This rise, however, was modest when compared with the rise in experimentally infected zebra. The presence of low levels of group- and type-specific antibodies in the serum of some free-living elephants is judged to be the result of natural hyper-immunization due to frequent exposure to infected biting insects. Elephants should therefore, despite the presence of low levels of antibodies, be regarded as poorly susceptible and unlikely to be a source of African horsesickness virus.

African Horse Sickness↗
PubMed1997

Predicting body weight from body measurements in Asian elephants (Elephas maximus).

Accurate estimates of body weight can be useful in the evaluations of feeding programs, nutritional status and general health, and in calculation of dose levels (such as for anesthesia)-thus providing a valuable tool for captive elephant management. We used body measurements of 75 Asian elephants (Elephas maximus) to predict body weight. Weight, heart girth, height at the withers, body length, and foot-pad circumference were measured. All possible linear regressions of weight on one, two, three, or four body measurements were calculated. The highest correlation with a single measurement was that between heart girth and weight (R2 = 0.90). The data were also divided into age groups (1-13, 18-28, 29-39, and 40-57 yr), and all possible linear regressions were calculated for each group (there were no elephants aged 14-17 yr). Adding body length or pad circumference to heart girth resulted in a slight increase in R2. We conclude that body weight in Asian elephants can be predicted from body measurements and that heart girth is the best predictor. A second body measurement might improve predictive accuracy for some age groups.

Age Factors↗
PubMed1998

Reproductive assessment of male elephants (Loxodonta africana and Elephas maximus) by ultrasonography.

Transrectal ultrasonography was performed on five wild and two captive male African elephants (Loxodonta africana) and four captive male Asian elephants (Elephas maximus) to develop standards for assessment of reproductive health and status. The entire internal urogenital tract was visualized ultrasonographically by using a 3.5 MHz or a 7.5-MHz transducer in combination with a probe extension adapted for elephant anatomy. The findings were verified by postmortem ex situ ultrasound examinations in several individuals of each species. Each part of the internal urogenital tract was sonographically detectable except for the bulbourethral glands and the cranial portion of the ureters and ductus deferentes, which were only observed in situ in the neonate. Each structure visualized was measured and described. The size and morphology of the urogenital structures, especially the accessory glands, were indicative of breeding status, if known. There was a notable difference between African and Asian males in the size and morphology of the prostate gland and a slight difference in the shape of the ampullae. No other structure showed significant species differences. The detection of the location and description of the testes may provide information for modifying present castration procedures. Furthermore, ultrasound examination of the male accessory glands may aid in the identification of potential semen donors for assisted reproduction programs in captive elephants.

Animals↗
PubMed1978

Arteriovenous anastomoses in the skin of seals. I. The Weddell seal Leptonychotes weddelli and the elephant seal Mirounga leonina (Pinnipedia: Phocidae).

The structure, distribution, density and innervation of arteriovenous anastomoses (AVAs) have been compared in the skin of Weddell and elephant seals, as part of a study of the structure and function of arteriovenous anastomoses in mammals. In both genera AVAs were coiled vessels with the segmental structure typical of "epithelioid" anastomoses and possessed a dense peripheral adrenergic innervation. In both Weddell and elephant seals there was no statistically significant difference between the mean density of AVAs in body skin and flipper skin. The majority, approximately 71% of AVAs occurred superficially in the dermis, fewer (23%) occurred in the deeper dermis, and 6% were present in the thick hypodermis (bubber). The density of AVAs in Weddell and elephant seals is approximately eight times greater than that reported in other animals and the superficial position of anastomoses over the whole of the body surface is characteristic of phocid seals. When open, AVAs in Weddell and elephant seals allow maximal heat loss from the skin surface by passing large volumes of blood into the superficial veins. AVAs in seals are important in dissipation of body heat, particularly when the animals are out of the water, and the entire surface area is thermoregulatory rather than specific regions such as the flippers.

Animals↗
PubMed2001

Disease risk and inter-institutional transfer of specimens in cooperative breeding programs: Herpes and the elephant species survival plans.

Managers of cooperative breeding programs and re-introduction projects are increasingly concerned with the risk of disease transmission when specimens are transferred among facilities or between facilities and the natural environment. We used data maintained in North American studbooks to estimate the potential risks of disease transmission by direct and indirect contact of specimens in the American Zoo and Aquarium Association's Elephant Species Survival Plan. Histological evidence for a novel herpesvirus disease transmitted between and within elephant species housed in North American facilities prompted an examination of the scope of possible transmission routes within the captive population. We found that, compared with other species managed through Species Survival Plans, elephants experience relatively few transfers between zoos. Nevertheless, the number of direct contacts with other elephants born during the study period of 1983-1996 (excluding stillbirths) was much higher than we had anticipated (&mgr; = 25 +/- 27; N = 59) and the number of potential indirect contacts was surprisingly large (&mgr; = 143 +/- 92; N = 59). Although these high rates of potential contacts complicate exact identification of infection pathways for herpesvirus, we were able to propose potential routes of transmission for the histologically identified cases. Furthermore, the extraction of data from studbooks allowed us to readily identify other specimens that did not succumb to the disease despite similar exposure. Moreover, we were able to identify other possible cases to recommend for histological examination. Herein we reveal the possibilities of multiple disease transmission pathways and demonstrate how complex the patterns of transmission can be, confounded by the unknown latency of this novel herpesvirus. This emphasizes the need for zoo veterinarians and cooperative breeding programs to consider the full potential for disease transmission associated with each and every inter-zoo transfer of specimens. Zoo Biol 20:89-101, 2001. Copyright 2001 Wiley-Liss, Inc.

Journal Article↗
PubMed2000

Unusually extensive networks of vocal recognition in African elephants.

Research on acoustic communication has often focused on signalling between territorial individuals or static neighbouring groups. Under these circumstances, receivers have the opportunity to learn to recognize the signals only of the limited number of conspecifics with which they are in auditory contact. In some mammals, however, social units move freely with respect to one another and range widely, providing individuals with opportunities to learn to recognize the signals of a wide range of conspecifics in addition to those of their immediate neighbours. We conducted playback experiments on African elephants, Loxodonta africana, in Amboseli National Park, Kenya, to determine the extent to which adult female elephants, which have a highly fluid social system, can recognize others in the population through infrasonic contact calls. Female elephants could distinguish the calls of female family and bond group members from those of females outside of these categories; moreover, they could also discriminate between the calls of family units further removed than bond group members, on the basis of how frequently they encountered them. We estimated that subjects would have to be familiar with the contact calls of a mean of 14 families in the population (containing around 100 adult females in total), in order to perform these discriminations. Female elephants thus appear to have unusually extensive networks of vocal recognition, which may prove to be typical of long-lived species that have both fluid social systems and the means for long-distance vocal communication. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1999

Analysis of the elephant trunk method in patients with extensive thoracic aortic aneurysm.

We assessed the appropriate length of an elephant trunk prosthesis based on our experience with 9 patients experiencing extensive thoracic aneurysms. There were 3 patients with a true aneurysm, 5 patients with a dissecting aortic aneurysm, and 1 patient with a true plus dissecting aortic aneurysm. The subjects were 4 men and 5 women and, at the time of operation, were from 38 to 74 years old. The second-stage operations were performed on 6 patients from 9 days to 6 months after the first-stage operation. In the first-stage operation, one patient died of pneumonia during the hospital stay and another died of multi-organ infarction after 15 months. In the second-stage operation, two patients died of brain hemorrhage in the chronic stage after the operation. The length of the elephant trunk prosthesis was 3 cm in the three early patients, and in one of them the elephant trunk could not be utilized due to its insufficient length. In the next three patients, the length was extended to 5 cm, but one of patient experienced an expansion of the aneurysm in the descending aorta due to a graft of insufficient length which could not decompress the aneurysmal wall. Therefore, in the last three patients, the length was further extended to 10 cm, and the second-stage operation was performed uneventfully on the 64th, 9th and 45th day, respectively after the first-stage operation within a continuous hospital stay. Neither expansion of the aneurysm nor thromboembolism was found during the waiting period for any of the second-stage operations. Accordingly, we recommend using a 10 cm elephant trunk prosthesis.

Adult↗
PubMed2000

Treatment of aortic arch dissection using the elephant trunk technique.

The elephant trunk technique was developed to facilitate multiple-stage treatment of extensive aneurysm of the thoracic aorta. However, little information is available concerning its usefulness for aortic dissection. From April 1992 to July 1998, we used the elephant trunk technique for treatment of aortic arch dissection in 22 patients (including 19 men) with a mean age of 58.5 years (range 21 to 85 years). Twelve patients presented with type A dissection (acute in 3 and chronic in 9), 3 with type B acute dissection, and 7 with "non A/non B" dissections with retrograde extension to the aortic arch or entry site located in the aortic arch without involvement of the ascending aorta. All patients had aneurysms of the descending (n = 7) or thoracoabdominal (n = 15) aorta. Procedures were performed under hypothermic circulatory arrest at between 15 degrees and 20 degrees C. Antegrade cerebral perfusion was used in three cases. The procedure was associated with aortic valve replacement and/or coronary bypass in 6 cases and bypass of one or more supraaortic vessels in 13. In two patients the distal end of the elephant trunk was attached with an endovascular prosthesis during the same procedure. The ensuing results in these patients indicate that the elephant trunk technique can be highly effective for treatment of complex aortic arch dissection.

Adult↗
PubMed2005

The reversed elephant trunk technique used for treatment of complex aneurysms of the entire thoracic aorta.

OBJECTIVE: A preferred technique for the staged treatment of patients with aneurysms involving the entire thoracic aorta is the elephant trunk technique, with replacement of the proximal (ascending and transverse aortic arch) aorta as the initial procedure. Some patients, however, need to have the distal aortic segments (descending and thoracoabdominal aorta) addressed during the first operation. We evaluated outcomes in a series of patients who underwent distal aortic replacement first using the reversed elephant trunk technique. METHODS: Thirty-eight patients underwent first-stage graft repair of the descending thoracic (n = 3) or thoracoabdominal (n = 35) aorta using the reversed elephant trunk technique. Twelve patients (32%) ultimately underwent second-stage aortic arch replacement after a mean interval of 3.9 months (range, 1.6-14 months). RESULTS: The operative mortality for the initial procedure was 16% (6/38 patients). One patient had a stroke (3%) and 1 patient developed paraparesis (3%). In the interval between the 2 procedures, there were 4 late deaths (4/32; 13%), 1 due to respiratory failure and 3 due to unknown causes. After the 12 completion procedures, there was 1 in-hospital death (8%) and there were no strokes. Five-year survival for the overall group was 51.3 +/- 10.8%. CONCLUSIONS: Surgical treatment of aneurysms involving the entire thoracic aorta remains challenging and is associated with substantial morbidity and mortality. The reversed elephant trunk technique facilitates staged repair in patients who require distal aortic replacement during the first operation.

Adult↗
PubMed2005

Secondary elephant trunk fixation with endovascular stent grafting for extensive/multiple thoracic aortic aneurysm.

Four patients who underwent secondary elephant trunk fixation by endovascular stent grafting are presented and the advantage of this method to treat multiple/extensive thoracic aortic aneurysm is discussed. In two of them, the elephant trunk installation has been performed at another hospital for extensive aortic aneurysm. In two other patients, the aortic arch replacement and the elephant trunk installation were performed through median sternotomy, initially for multiple aortic lesions, including both arch and descending aorta. No neurological deficit, stroke nor spinal cord injury was encountered during the follow-up period (24-40 months). The diameter of the aneurysms decreased markedly in three patients. In one patient, the aneurysm expanded gradually and type II endoleak was treated by coil embolization. In one patient, who showed marked shrinkage of the aneurysm, the stent graft kinked mildly. Based on the low mortality rate of well-established aortic arch surgery, concomitant elephant trunk installation which was followed by the secondary fixation with endovascular stent grafting might be useful to treat multiple/extensive thoracic aneurysm from distal arch to descending aorta.

Aged↗
PubMed2004

Placenta and fetal membranes of the four-toed elephant shrew, Petrodromus tetradactylus.

The four-toed elephant shrew is the only extant member of the genus Petrodromus. Some features of its placentation are found in other elephant shrews and may be important in consolidating the elephant shrews in the order Macroscelidea. These include implantation in an embryo chamber at the caudal end of the uterine horn; a large yolk sac; a large, lobulated allantoic sac; a distinct layer of proliferative trophoblastic cells between the labyrinthine and spongy zones of the placenta; an accessory epitheliochorial placenta; and the formation of a mesoplacenta by the decidua basalis. Of particular note are the large granulated cells that occupy the walls of decidual, myometrial and mesometrial arteries. They appear to be uterine natural killer cells. The persistence of a relatively large yolk sac and a large lobulated allantoic sac is a feature which Petrodromus and other elephant shrews share with other members of the superordinal clade Afrotheria.

Animals↗
PubMed2004

Serum leptin concentration during the terrestrial phase of the Southern elephant seal Mirounga leonina (Carnivora: Phocidae).

This study aimed to verify the serum leptin concentration during the terrestrial phase of the Southern elephant seal (Mirounga leonina) on Elephant Island (South Shetlands, Antarctica). Sera from 25 adult Southern elephant seals were analyzed. Leptin concentration was determined using the 125I radioimmunoassay method. Total protein, triglycerides, and cholesterol concentration were measured by spectrophotometric methods. Seals were grouped by sex and their physiological status (reproducing or molting seals). In reproducing seals, serum concentrations of leptin, total protein, triglycerides, and cholesterol were, respectively, 9.33+/-1.97 ng/ml, 6.87+/-0.09 g/dl, 98.26+/-2.12 mg/dl, and 232.17+/-41.18 mg/dl in males and 5.30+/-1.36 ng/ml, 6.44+/-0.29 g/dl, 109.01+/-3.34 mg/dl, and 219.20+/-26.65 in females (mean+/-1 SD). In molting seals, these values were 2.35+/-1.51 ng/ml, 7.42+/-0.25 mg/dl, 321.10+/-20.01 mg/dl, and 244.66+/-22.24 mg/dl in males and 2.94+/-1.89 ng/ml, 7.88+/-0.46 mg/dl, 197.54 mg/dl, and 224.55+/-16.70 mg/dl in females. In both males and females, there were no significant differences (P>0.05) in total protein and cholesterol concentration between reproducing and molting seals. However, both males and females showed higher leptin concentration (P<0.05) and lower triglyceride concentration (P<0.05) in the reproductive period than in the molt period. In the reproductive period, it was expected that the Southern elephant seal shows an inhibited hunger sensation, mobilizes stored energy, and stimulates the HPG axis. Results from the present study support this hypothesis and suggest that this strategy may be effected by the hormonal stimulation of leptin.

Adaptation, Physiological↗
PubMed2000

Lipid composition of blood platelets and erythrocytes of southern elephant seal (Mirounga leonina) and antarctic fur seal (Arctocephalus gazella).

Erythrocyte and blood platelet phospholipid compositions were studied in three elephant seals and two fur seals, two species of marine mammals living in the Subantarctic region feeding on preys rich in (n-3) polyunsaturated fatty acids. Results were compared with those reported for related species and humans. In erythrocytes, the phospholipid (PL) and cholesterol (CHOL) contents were lower in pinnipeds than in humans. Phosphatidylcholine (PC) levels were higher in elephant seals than in fur seals, with a reverse trend for phosphatidylethanolamine (PE) and phosphatidylserine (PS). Both species had lower SM/PC ratios and PE plasmalogen concentrations than human. Erythrocytes were richer in (n-3) fatty acids (FA) in pinnipeds than in humans. In platelets, the PL content was lower and the CHOL content higher in elephant seals than in humans or in other phocid seal species studied to date. The SM/PC ratio was much higher than in other seal species or in man. In both species, the proportion of PE plasmalogens was higher in platelets than in erythrocytes. PL were more saturated in elephant seals than in fur seals. These results suggest that the erythrocytes and platelets of wild marine mammals may prove useful models to study the influence of dietary lipids on the structure and hemostatic function of these cells.

Animals↗
PubMed2000

Amoxicillin pharmacokinetics in harbor seals (Phoca vitulina) and northern elephant seals (Mirounga angustirostris) following single dose intravenous administration: implications for interspecific dose scaling.

The pharmacokinetics of sodium amoxicillin after a single intravenous dose of 20 mg/kg were determined in ten harbor seals (Phoca vitulina) and ten northern elephant seals (Mirounga angustirostris). The seals ranged in age from 1 to 6 months and the mean weights were 11.7 kg (range, 9.5-18.5 kg) for harbor seals and 47.1 kg (range, 39.5-61.4 kg) for elephant seals. The median half-life of amoxicillin (quartiles) in harbor seals, 1.5 (1.0-3.1) h. was not statistically different from that of elephant seals, 2.0 (1.4-3.8) h, nor were the differences between the terminal elimination rate constants between the two species. The only statistically significant differences between species were for area-under-the-curve (AUC), and total systemic clearance. The lack of statistical significance for differences in the volume of distribution at steady-state (Vss) may have been due to minor differences in the time frame of data collection and dose administered between the two groups. A true physiologic difference in drug handling, possibly related to renal perfusion or tubal secretory efficiency could affect amoxicillin kinetics in these species, and longer administration intervals may be appropriate for elephant seals as compared to harbor seals when administering multiple dose amoxicillin therapy at 20 mg/kg.

Amoxicillin↗