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 163 records · Page 9Linked to original sources
PubMed1999

Hormone secretion in the asian elephant (Elephas maximus): characterization of ovulatory and anovulatory luteinizing hormone surges.

In the elephant, two distinct LH surges occur 3 wk apart during the nonluteal phase of the estrous cycle, but only the second surge (ovLH) induces ovulation. The function of the first, anovulatory surge (anLH) is unknown, nor is it clear what regulates the timing of these two surges. To further study this observation in the Asian elephant, serum concentrations of LH, FSH, progesterone, inhibin, estradiol, and prolactin were quantified throughout the estrous cycle to establish temporal hormonal relationships. To examine long-term dynamics of hormone secretion, analyses were conducted in weekly blood samples collected from 3 Asian elephants for up to 3 yr. To determine whether differences existed in secretory patterns between the anLH and ovLH surges, daily blood samples were analyzed from 21 nonluteal-phase periods from 7 Asian elephants. During the nonluteal phase, serum LH was elevated for 1-2 days during anLH and ovLH surges with no differences in peak concentration between the two surges. The anLH surge occurred 19.9+/-1.2 days after the end of the luteal phase and was followed by the ovLH surge 20.8+/-0.5 days later. Serum FSH concentrations were highest at the beginning of the nonluteal phase and gradually declined to nadir concentrations within 4 days of the ovLH surge. FSH remained low until after the ovLH surge and then increased during the luteal phase. Serum inhibin concentrations were negatively correlated with FSH during the nonluteal phase (r = -0.53). Concentrations of estradiol and prolactin fluctuated throughout the estrous cycle with no discernible patterns evident. In sum, there were no clear differences in associated hormone secretory patterns between the anLH and ovLH surge. However, elevated FSH at the beginning of the nonluteal phase may be important for follicle recruitment, with the first anLH surge acting to complete the follicle selection process before ovulation.

Animals↗
PubMed2001

Genetic and ultrastructural characterization of a European isolate of the fatal endotheliotropic elephant herpesvirus.

A male Asian elephant (Elephas maximus) died at the Berlin zoological gardens in August 1998 of systemic infection with the novel endotheliotropic elephant herpesvirus (ElHV-1). This virus causes a fatal haemorrhagic disease in Asian elephants, the so-called endothelial inclusion body disease, as reported from North American zoological gardens. In the present work, ElHV-1 was visualized ultrastructurally in affected organ material. Furthermore, a gene block comprising the complete glycoprotein B (gB) and DNA polymerase (DPOL) genes as well as two partial genes was amplified by PCR-based genome walking and sequenced. The gene content and arrangement were similar to those of members of the Betaherpesvirinae. However, phylogenetic analysis with gB and DPOL consistently revealed a very distant relationship to the betaherpesviruses. Therefore, ElHV-1 may be a member of a new genus or even a new herpesvirus subfamily. The sequence information generated was used to set up a nested-PCR assay for diagnosis of suspected cases of endothelial inclusion body disease. Furthermore, it will aid in the development of antibody-based detection methods and of vaccination strategies against this fatal herpesvirus infection in the endangered Asian elephant.

Animals↗
PubMed2005

Population pharmacokinetics of isoniazid in the treatment of Mycobacterium tuberculosis among Asian and African elephants (Elephas maximus and Loxodonta africana).

We recently described the clinical presentation and treatment of 18 elephants from six herds infected with TB. Treatment protocols and methods varied between herds to include both oral and rectal dosing using multiple drug doses and formulations. In this paper we present information regarding the pharmacokinetics (PK) of isoniazid (INH) in elephants and provide suggestions regarding initial treatment regimens. Forty-one elephants received INH daily by either oral or rectal administration with different formulations. Population PK analysis was performed using Non-linear Mixed Effect Modeling (NONMEM). Results of oral administration indicated that compared with premixed INH solution, the drug exposure was highest with a suspension prepared freshly with INH powder. When INH was concomitantly given as an admixture over food, Tmax was delayed and variability in drug absorption was significantly increased. Compared with oral administration, similar drug exposures were found when INH was dosed rectally. The data generated suggest that a starting dose of 7.5 mg/kg of INH is appropriate for initial TB treatment in elephants when premixed solution is administered directly into the oropharynx or rectal vault and 4 mg/kg are when INH is administered following immediate suspension from powdered form.

Administration, Oral↗
PubMed2005

Pharmacokinetics and i.m. bioavailability of ceftiofur in Asian elephants (Elephas maximus).

Captive elephants are prone to infections of the feet, lungs, and skin. Often treatment regimens are established with no pharmacokinetic data on the agents being used for treatment in these species. A pharmacokinetic study using ceftiofur (1.1 mg/kg) was conducted in four adult female captive Asian elephants (Elephas maximus) at Busch Gardens in Tampa, Florida. Elephants were given both i.v. and i.m. administrations in a complete crossover design with a 3-week washout period between treatments. Blood samples were collected prior to drug administration and at 0.33, 0.67, 1, 1.5, 2, 4, 8, 12, 24, 48 and 72 h postadministration. Ceftiofur analysis was performed using a validated liquid chromatography/mass spectrophotometric (LC/MS) assay. Plasma concentrations for the i.m. samples were lower than expected. The mean C(max) following i.m. administration was 1.63 microg/mL with a corresponding T(max) of 0.55 h. Following i.v. administration, the median V(d(ss)) was 0.51 L/kg and a median Cl(p) of 0.069 L/kg/h. Mean i.m. bioavailability was 19%. The results indicate that ceftiofur used at 1.1 mg/kg i.m. could be useful in elephants when given two to three times a day or alternatively, 1.1 mg/kg i.v. once daily, depending upon the MIC of the pathogen.

Animals↗
PubMed1987

Elephant prolactin: isolation and characterization.

Prolactin was isolated from anterior lobes of elephant pituitary glands. It consisted of 199 amino acids with three disulfide bridges and two tryptophan residues as found in prolactin from other species. The sequence of the NH2-terminal 28 amino acids was determined and shown homologous with the ovine hormone. In comparison with ovine prolactin, a marked difference was seen in the methionine content; the elephant hormone possessed only 18-34% lactogenic potency. The conformation of elephant prolactin was examined by zero order, second order and circular dichroism spectroscopy. The alpha helical content was estimated to be about 60%. In comparison with prolactins from other species, the second order spectra of elephant prolactin suggest that the local microenvironment for one or both tryptophan residues is somewhat different.

Amino Acids↗
PubMed1996

Testosterone secretion, musth behaviour and social dominance in captive male Asian elephants living near the equator.

Testosterone concentrations were measured in blood samples collected weekly over a 5 year period from six adult (19-40 year old) male Asian elephants (Elephas maximus maximus) living in captivity in Sri Lanka (7 degrees N), to investigate the relationship between androgen secretion and the occurrence of musth (temporal gland secretion, drip urination and aggressive behaviour). The testosterone profiles were very variable both within and between animals. Long-term phasic changes in blood concentrations of testosterone, associated with periods of musth, occurred in three of the six elephants, with the most pronounced cyclicity in the oldest animal. Musth occurred annually after periods of high androgen secretion and there was a positive correlation between the duration of musth and mean concentrations of testosterone during the previous 2 months. The time of musth, while consistent for an individual, was variable between animals. In four bulls living within one social group, there was a positive correlation between social rank and mean concentrations of testosterone over the 5 year study, and only the dominant animal showed periodic musth. Short-term changes in testosterone concentrations occurred in blood samples collected every 15 min for 7 h, and following the injection of 20 micrograms GnRH, consistent with regulation through the pulsatile secretion of LH. Overall, the results support the view that fully mature male Asian elephants living near the equator express an asynchronous, cyclical, circannual pattern of gonadal activity, with the cyclical pattern developing progressively from 20 to 40 years of age. The periodic increase in testosterone secretion during the gonadal cycle induces the development of musth; however, androgen withdrawal following a period of hypersecretion may be the cause of some aspects of musth behaviour (aggression, unpredictability, disobedience) which make bull elephants very difficult to manage in captivity.

Animals↗
PubMed2005

Elephants and human color-blind deuteranopes have identical sets of visual pigments.

Being the largest land mammals, elephants have very few natural enemies and are active during both day and night. Compared with those of diurnal and nocturnal animals, the eyes of elephants and other arrhythmic species, such as many ungulates and large carnivores, must function in both the bright light of day and dim light of night. Despite their fundamental importance, the roles of photosensitive molecules, visual pigments, in arrhythmic vision are not well understood. Here we report that elephants (Loxodonta africana and Elephas maximus) use RH1, SWS1, and LWS pigments, which are maximally sensitive to 496, 419, and 552 nm, respectively. These light sensitivities are virtually identical to those of certain "color-blind" people who lack MWS pigments, which are maximally sensitive to 530 nm. During the day, therefore, elephants seem to have the dichromatic color vision of deuteranopes. During the night, however, they are likely to use RH1 and SWS1 pigments and detect light at 420-490 nm.

Animals↗
PubMed2000

Facilitation of Asian elephant (Elephas maximus) standing immobilization and anesthesia with a sling.

An Asian elephant (Elephas maximus) required general anesthesia for orthopedic foot surgery. The elephant was unable to lie down, so it was placed in a custom-made sling, administered i.m. etorphine hydrochloride in the standing position, and lowered to lateral recumbency. General anesthesia was maintained with isoflurane administered through an endotracheal tube. After surgery, the isoflurane anesthesia was terminated, with immobilization maintained with additional i.v. etorphine. The elephant was lifted to the vertical position, and the immobilizing effects of etorphine were reversed with naltrexone. The suspension system and hoist for the sling were designed specifically for the elephant house.

Anesthesia, General↗
PubMed2000

Use of famciclovir for the treatment of endotheliotrophic herpesvirus infections in Asian elephants (Elephas maximus).

Two juvenile Asian elephants (Elephas maximus) presented with an acute onset of facial edema and lethargy. Examination of the oral cavity of each animal revealed cyanosis of the tip and distal margins of the tongue suggestive of endothelial inclusion body disease (EIBD) of elephants. Whole-blood samples were obtained, and polymerase chain reaction tests confirmed the presence of elephant herpesvirus. The animals were administered famciclovir (Famvir, SmithKline Beecham Pharmaceuticals, Philadelphia, Pennsylvania 19101, USA), a potent human anti-herpesvirus drug, in the course of their disease, and recovery followed a treatment regime of 3-4 wk. These are the first known cases of elephants surviving EIBD.

2-Aminopurine↗
PubMed2001

Epidemiology and diagnosis of Mycobacterium tuberculosis in captive Asian elephants (Elephas maximus).

The deaths of two Asian elephants (Elephas maximus) in August 1996 led the United States Department of Agriculture to require the testing and treatment of elephants for tuberculosis. From August 1996 to September 1999. Mycobacterium tuberculosis infection was confirmed by culture in 12 of 118 elephants in six herds. Eight diagnoses were made antemortem on the basis of isolation of M. tuberculosis by culture of trunk wash samples; the remainder (including the initial two) were diagnosed postmortem. We present the case histories, epidemiologic characteristics, diagnostic test results, and therapeutic plans from these six herds. The intradermal tuberculin test, enzyme-linked immunosorbent assay serology, the blood tuberculosis test, and nucleic acid amplification and culture are compared as methods to diagnose M. tuberculosis infection in elephants.

Animals↗
PubMed2001

A simple method of providing intermittent positive-pressure ventilation to etorphine-immobilized elephants (Loxodonta africana) in the field.

Five African elephants (Loxodonta africana) were immobilized with etorphine in Waza National Park, Cameroon, for the purpose of deploying radio/satellite tracking collars. A portable ventilator constructed from two high-flow demand valves and the Y-piece of a large animal anesthesia circuit was used to provide intermittent positive-pressure ventilation with 100% oxygen. Oxygenation status improved dramatically in all five elephants. In one hypoxemic elephant, arterial PaO2 increased from 40 to 366 mm Hg. The results of this study demonstrate that both oxygenation and ventilation can be readily controlled in etorphine-immobilized elephants even under remote field conditions.

Animals↗
PubMedDate not supplied

Mycobacterium tuberculosis infection as a zoonotic disease: transmission between humans and elephants.

Between 1994 and 1996, three elephants from an exotic animal farm in Illinois died of pulmonary disease due to Mycobacterium tuberculosis. In October 1996, a fourth living elephant was culture-positive for M. tuberculosis. Twenty-two handlers at the farm were screened for tuberculosis (TB); eleven had positive reactions to intradermal injection with purified protein derivative. One had smear-negative, culture-positive active TB. DNA fingerprint comparison by IS6110 and TBN12 typing showed that the isolates from the four elephants and the handler with active TB were the same strain. This investigation indicates transmission of M. tuberculosis between humans and elephants.

Animal Husbandry↗
PubMed1990

Serological evidence of herpesvirus infection in captive Asian elephants (Elephas maximus).

In mid 1988 a 3-yr-old Asian elephant (Elephas maximus) from a circus in Switzerland died following generalized manifestation of a herpesvirus infection. In an effort to determine prevalence of infection with the herpesvirus, and due to lack of a corresponding virus isolate, it was decided to evaluate contact animals and elephants from a second herd for antibody to bovine herpesvirus 1 (BHV1) and bovine herpesvirus 2 (BHV2). Of 15 sera tested four displayed low neutralizing antibody titers to BHV2. None of the sera neutralized BHV1. However, as evidenced by protein A-mediated immunoprecipitation of metabolically radio-labeled virus-infected and mock-infected cell antigens, followed by separation of precipitation products in SDS-polyacrylamide gels, the 15 sera precipitated multiple antigens from both viruses. Similar results were obtained when using BHV4 antigens. The extent of reaction was most distinct with respect to BHV2 antigens, less prominent with BHV1 antigens, and least with BHV4 antigens. The respective protein patterns, although less marked, matched well with those obtained with bovine reference sera. Additional evaluation of sera from six elephants from two zoos in the Federal Republic of Germany gave essentially identical results. It was concluded that at least one herpesvirus, immunologically related to BHV2, may be widely distributed among captive Asian elephants, and that this virus apparently does not cause overt disease in the majority of animals.

Animals↗
PubMed1997

Serological evidence of bovine herpesviruses 1 and 2 in Asian elephants.

Antibodies were detected against bovine herpesviruses 1 (BHV 1) and 2 (BHV 2) in Asian elephants (Elephas maximus) using the passive hemagglutination (PHA) test. The study was conducted during May to December 1994 using sera collected from zoological gardens and national parks in India. Four (4%) of 109 elephant sera had PHA titers ranging from 1:8 to 1:32 against BHV 1. Twenty-five (23%) of the 109 elephant sera had PHA titers ranging from 1:8 to 1:64 against BHV 2. Asian elephants appear to be better reservoirs for herpesviruses which are serologically related to BHV 2.

Animals↗
PubMed1999

Oxygen radical production by Asian elephant (Elephas maximus) heterophils and Holstein cattle (Bos taurus) neutrophils.

Oxidative metabolic burst activity by Asian elephant (Elephas maximus) heterophils and Holstein cattle (Bos taurus) neutrophils was indirectly evaluated by measuring the oxidation of nonfluorescent intracellular 2',7'-dichlorofluorescein (DCFH) to fluorescent 2',7'-dichlorofluorescein (DCF) with flow cytometry. The results were recorded as mean channel fluorescence intensity. Phorbol myristate acetate at 50 ng/ml was used to activate the cells. Elephant heterophils and bovine neutrophils exhibited similar abilities to oxidize intracellular DCFH to DCF, a fluorescent product. A wide range of mean channel fluorescence intensity (1,803-7,393) was observed among individual elephants, and the range of intensities was similar to that observed in bovine neutrophils, supporting the concept of functional heterogeneity of heterophils among elephants.

Animals↗
PubMedDate not supplied

Application of an enzyme-immunoassay (EIA) for rapid screening of 5 alpha-pregnane-3,20-dione (DHP) in blood plasma of the Asian elephant, Elephas maximus.

Populations of African (Loxodonta Africana) and Asian Elephants (Elephas maximus) in zoos and safari parks are at risk due to their low reproductive success. To extend the limited knowledge of their reproductive physiology, the development of easy and practical methods for the analysis of the relevant reproductive hormones is essential to support e.g. assisted reproduction. For the measurement of 5 alpha-pregnane-3,20-dione (DHP), the predominant ovarian gestagen in both species, an enzyme-immunoassay (EIA) based on commercial reagents was applied. Advantages of this EIA are the small volume of plasma needed for evaluation (5 microliters) and the possibility of direct processing without an extraction stage. The lower limit of detection was 0.16 ng/ml, the mean recovery was 101% and the mean coefficients of variation were 7.3% (intra-assay) and 9.9% (inter-assay). In Asian elephants, DHP levels reached 15 ng/ml during the luteal phase and up to 21 ng/ml during pregnancy. Estrous cycle lengths based on the lowest DHP concentrations varied from 12 to 20 weeks (mean 15.4 +/- 2.3). In two Asian elephant cows a calf was still-borne. Thereafter, the animals reassumed ovarian activity after approximately 8 and 13 weeks, respectively. In one animal estradiol implants for hormonal contraception caused a down regulation of the ovarian function as demonstrated by an irregular pattern of DHP secretion over a period of 48 weeks. We propose the direct DHP-EIA as a suitable method for reproductive monitoring in elephants, as it can be easily established in laboratories.

Animals↗
PubMed1988

Use of halothane to maintain anesthesia induced with etorphine in juvenile African elephants.

Sixteen 3- to 5-year-old African elephants were anesthetized one or more times for a total of 27 diagnostic and surgical procedures. Xylazine (0.1 +/- 0.04 mg/kg of body weight, mean +/- SD) and ketamine (0.6 +/- 0.13 mg/kg) administered IM induced good chemical restraint in standing juvenile elephants during a 45-minute transport period before administration of general anesthesia. After IM or IV administration of etorphine (1.9 +/- 0.56 micrograms/kg), the mean time to lateral recumbency was 20 +/- 6.6 and 3 +/- 0.0 minutes, respectively. The mean heart rate, systolic blood pressure, and respiration rate during all procedures was 50 +/- 12 beats/min, 106 +/- 19 mm of Hg, and 10 +/- 3 breaths/min, respectively. Cardiac arrhythmias were detected during 2 procedures. One elephant with hypotension responded to a decrease in the concentration of halothane and IV infusion of dobutamine HCl. Alterations in systolic blood pressure, ear flapping, and trunk muscle tone were useful for monitoring depth of anesthesia. Results indicated that halothane in oxygen was effective for maintenance of surgical anesthesia in juvenile African elephants after induction with etorphine.

Anesthesia↗
PubMed1985

Resonance Raman studies of CO and O2 binding to elephant myoglobin (distal His(E7)----Gln).

Carbon monoxide and dioxygen were employed as resonance Raman-visible ligands for probing the nature of the heme-binding site in elephant myoglobin, which has glutamine in the distal position (E7) instead of the usual histidine. The distal histidine (E7) residue has been thought to be responsible for weakening carbon monoxide binding to hemoproteins. It is of interest to see how the His(E7)----Gln replacement affects such parameters as nu(Fe-N epsilon), nu(Fe-CO), delta(Fe-C-O), nu(C-O), delta(Fe-O-O), and nu(O-O) vibrational frequencies and relative intensities. Elephant myoglobin has a CO affinity approximately 6 times higher than that for human/sperm whale myoglobin (Mb). If this enhanced affinity were solely due to the removal of some of the steric hindrance that normally tilts the CO off the heme axis, one would expect the nu(Fe-CO) frequency to decrease and the nu(C-O) frequency to increase relative to the corresponding values in sperm whale Mb. However, the opposite was found. In addition, strong enhancement of the Fe-C-O bending mode was observed. These results suggest that the Fe-C-O linkage remains distorted. In elephant Mb, new interactions resulting from the conformational change accompanying ligand binding may be responsible for the increased CO binding. Similar spectra were obtained for elephant and sperm whale oxymyoglobin. This suggests that the interactions of bound O2 are not markedly affected by the glutamine replacement.

Animals↗