Research

Cerling, T.E., G. Wittemyer, H.B. Rasmussen, F. Vollrath, C.E. Cerling, T.J. Robinson, and I. Douglas Hamilton (2006). Stable isotopes in elephant hair document migration patterns and diet changes. Proceedings of the National Academy of Sciences of the United States of America 103(2): 371-3.
NAL Call Number: 500 N31P
Abstract: We use chronologies of stable isotopes measured from elephant (Loxodonta africana) hair to determine migration patterns and seasonal diet changes in elephants in and near Samburu National Reserve in northern Kenya. Stable carbon isotopes record diet changes, principally enabling differentiation between browse and tropical grasses, which use the C3 and C4 photosynthetic pathways, respectively; stable nitrogen isotopes record regional patterns related to aridity, offering insight in to localized ranging behavior. Isotopically identified range shifts were corroborated by global positioning system radio tracking data of the studied individuals. Comparison of the stable isotope record in the hair of one migrant individual with that of a resident population shows important differences in feeding and ranging behavior over time. Our analysis indicates that differences are the result of excursions into mesic environments coupled with intermittent crop raiding by the migrant individual. Variation in diet, quantified by using stable isotopes, can offer insight into diet-related wildlife behavior.
Descriptors: animal migration, diet, physiology, hair chemistry, hair metabolism, carbon isotopes, metabolism, hair growth and development, nitrogen isotopes, seasons, time factors.

Clauss, M., Y. Wang, K. Ghebremeskel, C.E. Lendl, and W.J. Streich (2003). Plasma and erythrocyte fatty acids in captive Asian (Elephas maximus) and African (Loxodonta africana) elephants. Veterinary Record 153(2): 54-8.
NAL Call Number: 41.8 V641
Abstract: The fatty acid components of the plasma triglycerides and the phospholipid fractions of the red blood cells of a captive group of two African (Loxodonta africana) and four Asian (Elephas maximus) elephants were investigated. All the animals received the same diet of hay, fruits and vegetables, and concentrates. A comparison with data from free-ranging African elephants or Asian work-camp elephants showed that the captive elephants had lower proportions of polyunsaturated fatty acids (PUFAs), and for several lipid fractions a higher n-6:n-3 ratio, than their counterparts in the wild or under the more natural, in terms of diet, work-camp conditions. The difference in PUFA content was smaller in the African than in the Asian elephants. The captive Asian elephants tended to have lower levels of n-3 and total unsaturated fatty acids in their red blood cells than the captive African elephants.
Descriptors: metabolism, erythrocytes metabolism, unsaturated metabolism fatty acids, phospholipids metabolism, triglycerides metabolism, zoo animals, blood chemical analysis, diet, blood, unsaturated blood fatty acids, triglycerides blood, workload.

Dahl, N.J., D. Olson, D.L. Schmitt, D.R. Blasko, R.S. Kristipati, and J.F. Roser (2004). Development of an enzyme-linked immunosorbent assay (ELISA) for luteinizing hormone (LH) in the elephant (Loxodonta africana and Elephas maximus). Zoo Biology 23(1): 65-78. ISSN: 0733-3188.
NAL Call Number: QL77.5.Z6
Descriptors: African elephant, Asian elephant, ELISA, luteinizing hormone, enzyme-linked immunosorobent assay, LH, development.

Dill, W.M., B.L. Davis, A.R. Hicks, T.E. Goodwin, L.E.L. Rasmussen, H. Loizi, and B. Schulte (2003). Chemical analysis of preovulatory female African elephant urine: a search for putative pheromones. Abstracts of Papers American Chemical Society 225(1-2): CHED 409. ISSN: 0065-7727.
NAL Call Number: 381 Am33PA
Descriptors: African elephant, urinary system, chemical analysis, urine, putative pheromones, preovulatory, female.

Ganswindt, A., M. Heistermann, and K. Hodges (2005). Physical, physiological, and behavioral correlates of musth in captive African elephants (Loxodonta africana). Physiological and Biochemical Zoology 78(4): 505-14.
NAL Call Number: QL1.P52
Abstract: Although musth in male African elephants (Loxodonta africana) is known to be associated with increased aggressiveness, urine dribbling (UD), temporal gland secretion (TGS), and elevated androgens, the temporal relationship between these changes has not been examined. Here, we describe the pattern of musth-related characteristics in 14 captive elephant bulls by combining long-term observations of physical and behavioral changes with physiological data on testicular and adrenal function. The length of musth periods was highly variable but according to our data set not related to age. Our data also confirm that musth is associated with elevated androgens and, in this respect, show that TGS and UD are downstream effects of this elevation, with TGS responding earlier and to lower androgen levels than UD. Because the majority of musth periods were associated with a decrease in glucocorticoid levels, our data also indicate that musth does not represent a physiological stress mediated by the hypothalamic-pituitary-adrenal axis. Furthermore, we demonstrate that the occurrence of musth is associated with increased aggression and that this is presumably androgen mediated because aggressive males had higher androgen levels. Collectively, the information generated contributes to a better understanding of what characterizes and initiates musth in captive African elephants and provides a basis for further studies designed to examine in more detail the factors regulating the intensity and duration of musth.
Descriptors: zoo animals, physiology, reproduction physiology, sex behavior, animal physiology, adrenal glands physiology, aggression physiology, analysis of variance, androgens metabolism, feces chemistry, glucocorticoids metabolism, observation, testis physiology, time factors.

Ganswindt, A., R. Palme, M. Heistermann, S. Borragan, and J.K. Hodges (2003). Non-invasive assessment of adrenocortical function in the male African elephant (Loxodonta africana) and its relation to musth. General and Comparative Endocrinology 134(2): 156-66.
NAL Call Number: 444.8 G28
Abstract: Adult male elephants periodically show the phenomenon of musth, a condition associated with increased aggressiveness, restlessness, significant weight reduction and markedly elevated androgen levels. It has been suggested that musth-related behaviours are costly and that therefore musth may represent a form of physiological stress. In order to provide data on this largely unanswered question, the first aim of this study was to evaluate different assays for non-invasive assessment of adrenocortical function in the male African elephant by (i) characterizing the metabolism and excretion of [3H]cortisol (3H-C) and [14C]testosterone (14C-T) and (ii) using this information to evaluate the specificity of four antibodies for determination of excreted cortisol metabolites, particularly with respect to possible cross-reactions with androgen metabolites, and to assess their biological validity using an ACTH challenge test. Based on the methodology established, the second objective was to provide data on fecal cortisol metabolite concentrations in bulls during the musth and non-musth condition. 3H-C (1 mCi) and 14C-T (100 microCi) were injected simultaneously into a 16 year old male and all urine and feces collected for 30 and 86 h, respectively. The majority (82%) of cortisol metabolites was excreted into the urine, whereas testosterone metabolites were mainly (57%) excreted into the feces. Almost all radioactive metabolites recovered from urine were conjugated (86% 3H-C and 97% 14C-T). In contrast, 86% and >99% of the 3H-C and 14C-T metabolites recovered from feces consisted of unconjugated forms. HPLC separations indicated the presence of various metabolites of cortisol in both urine and feces, with cortisol being abundant in hydrolysed urine, but virtually absent in feces. Although all antibodies measured substantial amounts of immunoreactivity after HPLC separation of peak radioactive samples and detected an increase in glucocorticoid output following the ACTH challenge, only two (in feces against 3alpha,11-oxo-cortisol metabolites, measured by an 11-oxo-etiocholanolone-EIA and in urine against cortisol, measured by a cortisol-EIA) did not show substantial cross-reactivity with excreted 14C-T metabolites and could provide an acceptable degree of specificity for reliable assessment of glucocorticoid output from urine and feces. Based on these findings, concentrations of immunoreactive 3alpha,11-oxo-cortisol metabolites were determined in weekly fecal samples collected from four adult bulls over periods of 11-20 months to examine whether musth is associated with increased adrenal activity. Results showed that in each male levels of these cortisol metabolites were not elevated during periods of musth, suggesting that in the African elephant musth is generally not associated with marked elevations in glucocorticoid output. Given the complex nature of musth and the variety of factors that are likely to influence its manifestation, it is clear, however, that further studies, particularly on free-ranging animals, are needed before a possible relationship between musth and adrenal function can be resolved. This study also clearly illustrates the potential problems associated with cross-reacting metabolites of gonadal steroids in EIAs measuring glucocorticoid metabolites. This has to be taken into account when selecting assays and interpreting results of glucocorticoid metabolite analysis, not only for studies in the elephant but also in other species.
Descriptors: adrenal cortex metabolism, adrenal cortex function tests, metabolism, feces chemistry, hydrocortisone analysis, stress, psychological physiopathology, testosterone analysis, adrenal cortex secretion, adrenal cortex function tests methods, diagnostic use of carbon isotopes, high pressure liquid chromatography, corticotropin physiology, urine, glucocorticoids analysis, glucocorticoids in urine, diagnostic use of hydrocortisone, hydrocortisone in urine, immunoenzyme techniques and methods, reproduction physiology, sex behavior, animal physiology, psychological diagnosis of stress, diagnostic use of testosterone, testosterone in urine.

Ganswindt, A., H.B. Rasmussen, M. Heistermann, and J.K. Hodges (2005). The sexually active states of free-ranging male African elephants (Loxodonta africana): defining musth and non-musth using endocrinology, physical signals, and behavior. Hormones and Behavior 47(1): 83-91.
NAL Call Number: QP801.H7H64
Abstract: Musth in male African elephants, Loxodonta africana, is associated with increased aggressive behavior, continuous discharge of urine, copious secretions from the swollen temporal glands, and elevated androgen levels. During musth, bulls actively seek out and are preferred by estrous females although sexual activity is not restricted to the musth condition. The present study combines recently established methods of fecal hormone analysis with long-term observations on male-female associations as well as the presence and intensity of physical signals to provide a more detailed picture about the physical, physiological, and behavioral characteristics of different states of sexual activity in free-ranging African elephants. Based on quantitative shifts in individual bull association patterns, the presence of different physical signals, and significant differences in androgen levels, a total of three potential sub-categories for sexually active bulls could be established. The results demonstrate that elevations in androgen levels are only observed in sexually active animals showing temporal gland secretion and/or urine dribbling, but are not related to the age of the individual. Further, none of the sexually active states showed elevated glucocorticoid output indicating that musth does not represent an HPA-mediated stress condition. On the basis of these results, we suggest that the term "musth" should be exclusively used for the competitive state in sexually active male elephants and that the presence of urine dribbling should be the physical signal used for defining this state.
Descriptors: behavior, animal physiology, competitive behavior physiology, sex behavior, age factors, androsterone analysis, feces chemistry, hydrocortisone analysis, hydrocortisone metabolism, longitudinal studies, testosterone analysis.

Hatfield, J.R., D.A. Samuelson, P.A. Lewis, and M. Chisholm (2003). Structure and presumptive function of the iridocorneal angle of the West Indian manatee (Trichechus manatus), short-finned pilot whale (Globicephala macrorhynchus), hippopotamus (Hippopotamus amphibius), and African elephant (Loxodonta africana). Veterinary Ophthalmology 6(1): 35-43.
Abstract: The iridocorneal angles of prepared eyes from the West Indian manatee, short-finned pilot whale, hippopotamus and African elephant were examined and compared using light microscopy. The manatee and pilot whale demonstrated capacity for a large amount of aqueous outflow, probably as part of a system compensating for lack of ciliary musculature, and possibly also related to environmental changes associated with life at varying depths. The elephant angle displayed many characteristics of large herbivores, but was found to have relatively low capacity for aqueous outflow via both primary and secondary routes. The hippopotamus shared characteristics with both land- and water-dwelling mammals; uveoscleral aqueous outflow may be substantial as in the marine mammals, but the angular aqueous plexus was less extensive and a robust pectinate ligament was present. The angles varied greatly in size and composition among the four species, and most structures were found to be uniquely suited to the habitat of each animal.
Descriptors: cornea anatomy and histology, cornea physiology, mammals anatomy and histology, mammals physiology, aqueous humor physiology, Artiodactyla anatomy and histology, Artiodactyla physiology, elephant anatomy and histology, elephant physiology, species specificity, Trichechus manatus anatomy and histology, Trichechus manatus physiology, whale anatomy and histology, whale physiology.

Hunt, K.E. and S.K. Wasser (2003). Effect of long-term preservation methods on fecal glucocorticoid concentrations of grizzly bear and African elephant. Physiological and Biochemical Zoology 76(6): 918-928. ISSN: 1522-2152.
NAL Call Number: QL1.P52
Descriptors: African elephant, fecal glucocorticoid, concentrations, long term preservation, effects, grizzly bear.

Jones, C.J., F.B. Wooding, S.S. Mathias, and W.R. Allen (2004). Fetomaternal glycosylation of early placentation events in the African elephant Loxodonta africana. Placenta 25(4): 308-20.
NAL Call Number: QP281.P53
Abstract: During implantation in the African elephant (Loxodonta africana), fetal trophoblast displaces the surface uterine epithelium and superficially penetrates the uterine glands. This limited invasion is followed by the upgrowth of blunt fingers of endometrial stroma, covered with trophoblast and containing capillaries that subsequently vascularize the growing placenta. We have used lectin histochemistry to compare the glycosylation of maternal endothelial cells in the endometrium with those growing within the trophoblastic processes of a 2 g embryo (approximately 125 days' gestation), and also examine changes in the endometrial glands associated with trophoblastic invasion. Maternal vessels at the apices of the trophoblast-covered stromal upgrowths showed increased expression of terminal N-acetyl galactosamine, N-acetyl glucosamine oligomers, some sialic acids, and tri/tetra-antennate non-bisected complex N-linked glycan, as indicated by increased lectin staining. The areas of increased staining were also more resistant to neuraminidase digestion. Invaded glands had distended walls composed of flattened epithelial cells, some of which showed heavy lectin staining suggestive of intracellular glycan accumulation. The vascular changes suggest that new maternal capillary growth is accompanied by alterations in surface glycosylation. This may be the result of increased glycosyl transferase activity associated with cell proliferation and may also indicate the expression of significantly increased anti-adhesive molecules preventing blood stasis and egress of maternal immunocompetent cells into the fetal compartment.
Descriptors: physiology, embryo implantation physiology, maternal fetal exchange physiology, trophoblasts metabolism, biological markers analysis, endometrium metabolism, gestational age, glycosylation, immunoenzyme techniques, lectins metabolism.

Morshedi, R.G., P. Brown, T.E. Goodwin, L.E.L. Rasmussen, and B. Schulte (2004). Heterocycles (and other compounds) that we have identified in African elephant urine: a search for putative pheromones. Abstracts of the American Chemical Society 227(Part 1): U639. ISSN: 0065-7727.
NAL Call Number: 381 Am33Pa
Descriptors: African elephant, urine, putative hormones, heterocycles, other compounds, search.

Okello, J.B., G. Wittemyer, H.B. Rasmussen, I. Douglas Hamilton, S. Nyakaana, P. Arctander, and H.R. Siegismund (2005). Noninvasive genotyping and Mendelian analysis of microsatellites in African savannah elephants. Journal of Heredity 96(6): 679-87.
NAL Call Number: 442.8 Am3
Abstract: We obtained fresh dung samples from 202 (133 mother-offspring pairs) savannah elephants (Loxodonta africana) in Samburu, Kenya, and genotyped them at 20 microsatellite loci to assess genotyping success and errors. A total of 98.6% consensus genotypes was successfully obtained, with allelic dropout and false allele rates at 1.6% (n = 46) and 0.9% (n = 37) of heterozygous and total consensus genotypes, respectively, and an overall genotyping error rate of 2.5% based on repeat typing. Mendelian analysis revealed consistent inheritance in all but 38 allelic pairs from mother-offspring, giving an average mismatch error rate of 2.06%, a possible result of null alleles, mutations, genotyping errors, or inaccuracy in maternity assignment. We detected no evidence for large allele dropout, stuttering, or scoring error in the dataset and significant Hardy-Weinberg deviations at only two loci due to heterozygosity deficiency. Across loci, null allele frequencies were low (range: 0.000-0.042) and below the 0.20 threshold that would significantly bias individual-based studies. The high genotyping success and low errors observed in this study demonstrate reliability of the method employed and underscore the application of simple pedigrees in non invasive studies. Since none of the sires were included in this study, the error rates presented are just estimates.
Descriptors: DNA analysis, genetics, feces chemistry, genetic techniques, microsatellite repeats genetics, genotype, Kenya, polymerase chain reaction methods.

Osthoff, G., H.O. De Waal, A. Hugo, M. de Wit, and P. Botes (2005). Milk composition of a free-ranging African elephant (Loxodonta africana) cow during early lactation. Comparative Biochemistry and Physiology. Part A, Molecular and Integrative Physiology 141(2): 223-9.
NAL Call Number: QP1.C6
Abstract: Only one study previously reported comprehensively on the composition of African elephant's (Loxodonta africana) milk that was collected from 30 dead animals. In the current study milk was obtained from a tame but free-ranging African elephant cow without immobilization during the period when she was 4-47 days postpartum. At the respective collection times the nutrient content was 21.8 and 25.0 g protein; 56.0 and 76.0 g fat; 71.1 and 26.0 g sugars per kilogram of milk. The protein fraction, respectively, consisted of 10.0 and 14.0 g caseins/kg milk and of 11.8 and 11 g whey proteins/kg milk. During lactation the lactose content dropped from 52.5 to 11.8 g/kg milk, while the oligosaccharide content increased from 11.8 to 15.2 g/kg milk. The oligosaccharide was characterized as a galactosyllactose, which is digestible by cellulase. Electrophoresis and identification of protein bands showed a similar migrating sequence of proteins as seen in cow's milk, but some of the corresponding proteins were less negatively charged. The lipid fraction contains a high content of capric and lauric acids, approximately 60% of the total fatty acids, and low content of myristic, palmitic and oleic acids.
Descriptors: physiology, lactation physiology, milk chemistry, albumins analysis, carbohydrates analysis, caseins analysis, cattle, fatty acids analysis, globulins analysis, milk proteins analysis.

Pitts, N.I. and G. Mitchell (2003). In vitro succinylcholine hydrolysis in plasma of the African elephant (Loxodonta africana) and impala (Aepyceros melampus). Comparative Biochemistry and Physiology. Toxicology and Pharmacology 134(1): 123-9.
NAL Call Number: QP901.C6
Abstract: In elephants the time lapsed from i.m. injection of an overdose of the muscle relaxant succinylcholine (SuCh) until death, is significantly longer than in impala. To determine a difference in the rate of SuCh hydrolysis, once the drug enters the circulation, contributes to this phenomenon we have measured the rate of hydrolysis of SuCh in elephant and impala plasma, and by elephant erythrocytes. Rate of hydrolysis was determined by incubating SuCh in plasma or erythrocyte lysate at 37 degrees C and quantifying the choline produced. Plasma SuCh hydrolytic activity in elephant plasma (12.1+/-1.7 Ul(-1) mean+/-S.D.; n=9) was significantly higher than it was in impala plasma (6.6+/-0.6 Ul(-1); n=5), but were approximately 12 and 21 times lower, respectively, than in human plasma. Elephant erythrocyte lysate had no SuCh hydrolytic activity. Applying this data to previous studies, we can show that the ratio of SuCh absorption to SuCh hydrolysis is expected to be 1.25:1 and 1.41:1 for elephants and impala respectively. It will thus take at least 1.7 times longer for elephant to achieve a plasma SuCh concentration similar to that in impala. We conclude that a more rapid hydrolysis of SuCh in elephant plasma is one factor that contributes to the longer time to death compared to impala.
Descriptors: antelopes metabolism, elephants metabolism, erythrocytes metabolism, neuromuscular depolarizing agents metabolism, succinylcholine metabolism, butyrylcholinesterase metabolism, cultured cells, choline analysis, choline metabolism, erythrocytes drug effects, hydrolysis drug effects, neuromuscular depolarizing agents pharmacology, species specificity, succinylcholine pharmacology.

Rasmussen, H.B., G. Wittemyer, and I. Douglas Hamilton (2005). Estimating age of immobilized elephants from teeth impressions using dental silicon. African Journal of Ecology 43(3): 215-219. ISSN: 0141-6707.
NAL Call Number: 409.6 EA7
Descriptors: Loxodonta africana, African elephant, estimating age, teeth impressions, dental silicon, molars, lower jaw.
Language of Text: English, with English and French summaries.

Satterfield, G.L., R.G. Morshedi, R. Kopper, T.E. Goodwin, C.F. Lichti, L.E.L. Rasmussen, and B. Schulte (2004). Use of sds page, hplc-ms/ms, and spme, gc-ms to study female African elephant urinary proteins. Abstracts of Papers American Chemical Society 227(Part 1): U443. ISSN: 0065-7727.
NAL Call Number: 381 Am33PA
Descriptors: African elephant, urinary proteins, female, study, SDS page, HPLC-MS, MS, GC-MS.

Stumpf, P. and U. Welsch (2004). Secretory and defensive functions of the duct system of the lactating mammary gland of the African elephant (Loxodonta africana, Proboscidea). Zoomorphology (Berlin) 123(3): 155-167. ISSN: 0720-213X.
NAL Call Number: 442.8 Z33
Descriptors: African elephant, mammary gland, lactating, duct system, secretory, defensive functions, microorganisms, invading, IgA, lactation period.

Wilson, M.L., M.A. Bloomsmith, and T.L. Maple (2004). Stereotypic swaying and serum cortisol concentrations in three captive African elephants (Loxodonta africana). Animal Welfare 13(1): 39-43. ISSN: 0962-7286.
NAL Call Number: HV4701.A557
Descriptors: zoo animals, stereotyped behavior, cortisol, animal welfare.