Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Elephants”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources

Outbreak of Mycobacterium tuberculosis infection among captive Asian elephants in a Swedish zoo.

Between 2001 and 2003, there was an outbreak of tuberculosis in a Swedish zoo which involved elephants, giraffes, rhinoceroses and buffaloes. Cultures of trunk lavages were used to detect infected elephants, tuberculin testing was used in the giraffes and buffaloes, and tracheal lavage and tuberculin testing were used in the rhinoceroses. The bacteria isolated were investigated by spoligotyping and restriction fragment length polymorphism. Five elephants and one giraffe were found to have been infected by four different strains of Mycobacterium tuberculosis.

Animals↗

Stereotypic behavior of a female Asiatic elephant (Elephas maximus) in a zoo.

This study recorded daytime behavior of a female Asiatic elephant at the Municipal Zoo, Wroclaw, Poland, in both an indoor pen and an outdoor paddock as continuous scan sampling for 140 hr, over 35 days in 1 year. Stereotypic sequences involved bouts of highly repetitive stereotypic movements and much more variable interbout behavior. The study found both stereotypic movements, nodding and body (corpus) swaying, were asymmetric, accompanied by protraction of the right hind leg and to-and-fro swinging of the trunk. The elephant spent 52% of the daytime in stereotypic movements, 3.5 times the level reported for females in other zoos' groups. The share of time devoted to stereotypic behavior was lowest in the summer when the elephant was regularly released to the paddock and highest in the late fall after she had stayed in the pen after months of days outside. This suggests that changes in the management routine enhance stereotypies. Comparing the summer and winter stable management periods, stereotypies were much more frequent in the indoor pen than the outdoor paddock, suggesting that the confinement to a barren pen contributed to the observed levels of stereotypies.

Animal Husbandry↗

Atmospheric controls on elephant communication.

Atmospheric conditions conducive to long-range transmission of low-frequency sound as used by elephants are found to exist in the Etosha National Park in Namibia during the late dry season. Meteorological measurements show that strong temperature inversions form at the surface before sunset and decay with sunrise, often accompanied by calm wind conditions during the early evening. These observations are used in an acoustic model to determine the sensitivity of infrasound to the effects of (a) the strength, thickness and elevation of temperature inversions, and (b) the growth and decay of an inversion typical of dry, elevated African savannas. The results suggest that the range over which elephants communicate more than doubles at night. Optimum conditions occur 1-2 h after sunset on clear, relatively cold, calm nights. At these times, ranges of over 10 km are likely, with the greatest amplification occurring at the lowest frequency tested. This strong diurnal cycle in communication range may be reflected in longer-lasting changes in weather and may exert a significant influence on elephant behaviour on time scales from days to many years.

Acoustics↗

Phosphate-haemoglobin interaction. The primary structure of the haemoglobin of the African elephant (Loxodonta africana, Proboscidea): asparagine in position 2 of the beta-chain.

The primary structure of the haemoglobin of the African Elephant (Loxodonta africana) is reported. The sequence was determined by means of a sequenator. The haemoglobin differs in 26 amino acids in the alpha-chains and in 27 in the beta-chains from that of adult human haemoglobin. The haemoglobin of the African Elephant, like that of the Indian Elephant and Ilama, has only 5 binding sites for polyphosphate. This finding explains the low p(O2)50 value in whole blood as a result of the lower 2,3-bisphosphoglycerate-haemoglobin interaction. This is discussed in relation to aspects of respiratory physiology; some points are also of interest with regard to the Second Punic War and Hannibal's crossing of the Alps.

2,3-Diphosphoglycerate↗

Short and long phases of progesterone secretion during the oestrous cycle of the African elephant (Loxodonta africana).

Serum samples were collected from 3 mature female African elephants once each week for 15-18 months. Circulating concentrations of progesterone, oestradiol and LH were determined by radioimmunoassay (RIA). The LH RIA was validated by demonstrating parallel cross-reaction with partly purified elephant LH pituitary fractions. Changing serum progesterone concentrations indicated an oestrous cycle length of 13.3 +/- 1.3 weeks (n = 11). The presumed luteal phase, characterized by elevated serum progesterone values, was 9.1 +/- 1.1 weeks (n = 11). Two abbreviated phases of progesterone in serum lasting 2-3 weeks were observed in 2 elephants, indicating short luteal phases. Oestradiol concentrations in serum were variable, with no clear pattern of secretion. More frequent blood samples were collected during periovulatory periods and 9 distinct LH peaks were detected; all were followed by rises in serum progesterone concentrations. Periovulatory changes in progesterone and LH in sera correlated with external signs of oestrus and mating behaviour.

Animals↗

Progestin content and biosynthetic potential of the corpus luteum of the African elephant (Loxodonta africana).

The aim of this study was to examine the progestin content and biosynthetic potential of the corpus luteum of the African elephant (Loxodonta africana). Luteal tissue was collected from nonpregnant and early, mid- and late pregnant elephants (n = 2 per group) shot in the Kruger National Park. Pieces of individual corpora lutea (2-3 per animal; 23 in total) were stored directly in ethanol before hormone analysis. Matching tissue pieces were incubated for 2 h with [3H]pregnenolone (2 x 10(5) c.p.m.), after which tissue plus medium were also stored in ethanol. Progesterone and 17 alpha-hydroxyprogesterone immunoreactivity in tissue extracts were determined by enzymeimmunoassay and radioimmunoassay, respectively, before and after reverse phase HPLC. Progesterone immunoreactivity predominated over that of 17 alpha-hydroxyprogesterone in all corpora lutea examined but concentrations of both hormones were very low (73-374 ng g-1 and 3-93 ng g-1, respectively after HPLC). There were no obvious differences in hormone concentrations in corpora lutea from animals at different reproductive stages. Progesterone and 17 alpha-hydroxyprogesterone immunoreactivity assayed before HPLC was 10-30 times higher than that measured after chromatographic separation. HPLC consistently revealed two large immunoreactive peaks associated with relatively nonpolar compounds, which together accounted for most (at least 75%) of all progesterone immunoreactivity measured. Large amounts of radioactivity with the same retention times as these peaks were also detected after HPLC in samples incubated with [3H]pregnenolone. Analysis of conversion products from four corpus luteum incubations indicated that between 52% and 84% of [3H]pregnenolone had been converted; 19-33% was accounted for by progesterone, and 12-50% by the two substances represented by the unidentified peaks. Subsequent GCMS analysis identified the two immunoreactive peaks as 5 alpha-pregnane-3 alpha-ol-20-one and 5 alpha-pregnane-3,20-dione (5 alpha-dihydroprogesterone). These results indicate that the major progestins contained within and biosynthesized by corpora lutea of African elephants are 5 alpha-reduced metabolites, and that progesterone and 17 alpha-hydroxyprogesterone are quantitatively of minor importance.

17-alpha-Hydroxyprogesterone↗

Placentation in the African elephant, Loxodonta africana. IV. Growth and function of the fetal gonads.

The gonads, both ovaries and testes, of 44 elephant fetuses weighing 0.09-112 kg (6.1-21.3 months gestation) were examined grossly and histologically. As in equids, elephant fetal gonads undergo a phase of marked growth and enlargement during the second half of gestation, which is more pronounced in ovaries than testes due to growth and antrum formation of numerous follicles in the former. Stromal cells undergo hypertrophy and transformation to form zones of interstitial cells that are associated with the enlarged follicles in the ovaries and in which the primitive seminiferous tubules are embedded in the testes. The interstitial cells have the capacity to synthesize 5alpha-dihydroprogesterone and other 5alpha-reduced progestagens from cholesterol and pregnenelone and the hypothesis is raised that these fetal gonadal progestagens may supplement significantly the progestagens secreted by the multiple large corpora lutea of pregnancy in the elephant.

Animals↗

Control of musth in an Asian elephant bull (Elephas maximus) using leuprolide acetate.

The results of long-term administration of leuprolide acetate (LA) depot in a 52-yr-old Asian elephant bull (Elephas maximus) for control of musth are presented. Twelve injections were administered for 6 yr during our interpretation of early musth or "premusth." Intervals between musth periods during the study varied from 2 to 34 mo. Blood samples, drawn weekly, were assayed for serum testosterone concentrations; mean levels were 11.78 +/- 1.97 nmol/L throughout the first 26 mo of the study, 7.28 +/- 1.28 nmol/L during the following 21 mo, and 0.45 +/- 0.035 nmol/L in the last 34 mo of this study. Early musth signs ceased within 3 days of drug administration after 10 of 12 injections. The mean serum testosterone concentrations were significantly decreased by the last 34 mo of the study. The results suggest leuprolide is a suitable alternative for controlling or preventing (or both) musth in captive Asian elephants, although permanent reproductive effects may occur. Zoos and wildlife conservation institutions could benefit from the use of LA in Asian elephants to increase the male availability in captivity, consequently ensuring genetic diversity and the perpetuation of the species.

Aggression↗

Seroprevalence of Toxoplasma gondii in elephants (Elephus maximus indicus) in Thailand.

Serum samples from captive 156 elephants (Elephus maximus indicus) from Thailand were examined for antibodies to Toxoplasma gondii using the modified agglutination test (MAT) and the latex agglutination test (LAT). Antibodies to T. gondii were found in 45.5% of 156 elephants by MAT (> or = 1:50) and 25.6% of 156 elephants by LAT (> or = 1:64). This is the first report of T. gondii infection in E. maximus indicus from Asia.

Animals↗

Investigating the depth of thermal burns in elephants.

Histological examination of burn injuries in elephants revealed that the depth was not as severe as expected from clinical observation. Although the actual burn depth was deep, the thickness of elephant skin, especially the dermis, resulted in the lesions being classified as less severe than expected. Examination of skin samples from selected areas showed that most lesions were either superficial (1st degree) or superficial partial-thickness (superficial 2nd degree) burns with the occasional deep partial thickness (deep 2nd degree) wound. These lesions however, resulted in severe complications that eventually led to the death of a number of the elephants.

Animals↗

[Keeping of elephants in the zoo and circus].

There is a decrease in the number of elephants kept in European zoological gardens and circus companies. In the future the import of animals will only be possible for holders which are able to keep family-groups of elephants under species-specific conditions. This will not be possible under circus conditions. This article will describe some problems observed in elephant holdings in zoological gardens and circus companies.

Animal Husbandry↗

Placentation in the African elephant, Loxodonta africana. I. Endocrinological aspects.

Placental and fetal tissues were recovered from the uteri of 59 pregnant elephant that ranged in estimated age from day 18 to month 21 of gestation. Incubation of placenta and fetal gonad, alone or in combination, with tritium-labelled cholesterol, pregnenolone and androstenedione failed to yield any labelled progestagens or oestrogens from placenta, but did produce small amounts of labelled progesterone and 5alpha-dihydroprogesterone from fetal gonad. Immunochemical staining of tissues with four antisera specific for enzymes involved in the steroidogenic pathway revealed no staining in sections of placenta but positive labelling for P450 side chain cleavage enzyme (SCC450) and 3beta-hydroxysteroid dehydrogenase (3beta-HSD) of the interstitial cells that comprise the bulk of the enlarged fetal gonads during the second half of gestation. Saline extracts of placental tissue showed no activity in three different gonadotrophin assays. In view of this endocrinological inactivity in the zonary elephant placenta and the probable reliance on maternal luteal sources of progestagens for maintenance of the pregnant state, the argument is advanced that uncomplicated abortion would probably follow a single administration of a PGF analogue given at any stage of pregnancy. If so, the treatment might constitute an efficacious method for controlling population increases in elephants maintained in enclosed game parks in Africa.

20-alpha-Dihydroprogesterone↗

Field applications of immunocontraception in African elephants (Loxodonta africana).

The primary aim of the Makalali elephant immunocontraception programme is to test the efficacy of porcine zona pellucida (PZP) vaccine for practical population control of elephants in small, enclosed reserves, with the goal of stabilizing the current growth rate and reducing it to the 5-10% per annum displayed currently in the Kruger National Park. A secondary aim is to test the hypothesis that PZP treatment does not affect patterns of elephant social behaviour. Eighteen sexually mature cows (age > 12 years) were vaccinated in May 2000 using remote darts. Behavioural observations before, during and after vaccination included noting the activity of individual animals every minute for 15 min. No changes in general behaviour patterns have been noted to date although the animals' spatial use of the reserve was erratic during the period of vaccination, indicating irregular or disturbed patterns associated with vaccination. Normality was resumed on completion of the vaccinations. No aggressive or indifferent behaviour related to nursing, calf proximity or bull-cow interactions have been noted. Ten of the females were in various stages of pregnancy when treated. Subsequently, seven of them gave birth to healthy calves and the other three females are expected to calve shortly. It is too early in the study to draw conclusions about stabilization of growth rates.

Animals↗

Afrotropical Culicoides: C. (Avaritia) loxodontis sp. nov., a new member of the Imicola group (Diptera: Ceratopogonidae) associated with the African elephant in the Kruger National Park, South Africa.

Culicoides (Avaritia) loxodontis sp. nov., is described and illustrated from both sexes collected in South Africa. It is the 5th species of the Imicola group of the subgenus Avaritia to be described from the Afrotropical Region, and is presently known only from the Kruger National Park where it has been collected in light-traps and reared from the dung of the African elephant (Loxodonta africana) on various occasions. A number of character states, and statistical analyses of antennal and palpal measurements, are used to separate the new species from its taxonomic congeners C. imicola Kieffer, 1913, C. pseudopallidipennis Clastrier, 1958, C. bolitinos Meiswinkel, 1989 and C. miombo Meiswinkel, 1991. It is suggested that the occurrence of the African elephant is the primary factor that determines the distribution of Culicoides loxodontis sp. nov., and that this close association, coupled with the fact that C. loxodontis sp. nov. can be locally abundant, may result in the cycling of certain arboviruses between this biting midge and the elephant.

Animals↗

The role of ivory in the survival of the African elephant.

The unique chequered pattern of polished ivory has created a perverted commercial demand for elephant tusks. The morphologic basis of the pattern, which makes ivory a sought after product for the manufacturing of works of art, is discussed. Chemical analyses of ivory holds great potential in tracing the source of illegally harvested tusks and exposing poorly managed elephant sanctuaries. The impact of uncontrolled ivory hunting on the population genetics of the African elephant is briefly reviewed.

Africa↗

[Treatments for elephants: a challenge fo the zoo veterinarian].

The existence of the elephant is heavily threatened. It is of great importance--for saving our largest land mammal on earth--to research into biology of the elephant quickly and thoroughly. Keeping elephants in Zoos and circus should be improved, breeding efforts must be enhanced and veterinary treatment has to be intensified. This is imperative for all zoo veterinarians.

Animal Diseases↗

[Hemoglobins, XLVIII: the primary structure of hemoglobin of the Indian elephant (Elephas maximus, Proboscidea): beta 2 = Asn].

The primary structure of the hemoglobin of the Indian Elephant (Elephas maximus) is given. The sequence was determined automatically in a sequenator. By homologous comparison with adult human HbA, the alpha-chains differ by 24 exchanges and the beta-chains by 27 exchanges. Furthermore, we report p(O2)50 values with regard to altered contact sites with 2,3-bisphosphoglycerate in Indian elephant hemoglobin. Our findings explain the low p(O2)50 and the reduced interaction with 2,3-bisphosphoglycerate. Elephant hemoglobin has, like that of the Llama, only five phosphate binding sites. In addition, we have made an attempt to relate these results to aspects of respiratory physiology. Some implications of these biochemical and physiological results, concerning the Second Punic War and Hannibal's Alp transition, are given.

Amino Acid Sequence↗

Excitement in an elephant after intravenous administration of atropine.

A 28-year-old Asian elephant (Elephas maximus) was anesthetized for cesarean section to remove a dead calf. The elephant was sedated with azaperone, and atropine was administered IV 90 minutes later in preparation for induction of anesthesia with etorphine HCl. Within 1 minute of injection of atropine, the elephant began swaying, kicking, and moving in an agitated manner around the stall. There is considerable variation among species in the toxicity of atropine, although development of toxicosis usually is associated with overdosage.

Anesthesia↗