Agnew, D.W., L. Munson, and E.C. Ramsay (2004). Cystic endometrial hyperplasia in elephants. Veterinary Pathology 41(2): 179-83.
NAL Call Number: 41.8 P27
Abstract: Most captive female elephants are nulliparous and aged and many have endometrial disease, factors that may hinder fertility. This study characterized the pathologic features and demographic distribution of endometrial lesions from 27 captive Asian (Elephas maximus) and 13 African elephants (Loxodonta africanus), 12- to 57-years of age. The principal lesion was marked cystic and polypoid endometrial hyperplasia (CEH), present in 67% of Asian and 15% of African elephants ranging from 26 to 57 years. The lower prevalence in African elephants likely reflects their younger age range in this study. Fourteen of 15 affected elephants with breeding information were nulliparous. These results suggest that CEH and polyps are common in aged nulliparous elephants, and the severity of these lesions may impair fertility. These findings will be useful in the interpretation of ultrasonographic findings during reproductive examinations of potential breeding cows. Also, breeding programs should focus on younger animals.
Descriptors: zoo animals, endometrial hyperplasia, endometrium pathology, fertility physiology, polyps, endometrial hyperplasia pathology, histological techniques, polyps pathology, species specificity.
Ball, R.L., J.L. Brown, J. Meyer, J. St. Leger, and J.H. Olsen (2004). Treatment of anestrus due to hyperprolactinemia with cabergoline in a captive Asian elephant (Elephas maximus). Proceedings: American Association of Zoo Veterinarians, American Association of Wildlife Veterinarians, Wildlife Disease Association: Health and Conservation of Captive and Free-Ranging Wildlife. Joint Conference,August 28, 2004-September 3, 2004, San Diego, California, American Association of Zoo Veterinarians: p. 363-365. 660 p.
Descriptors: Asian elephant, anestrus, treatment, hyperprolactinemia, Elephas maximus, cabergoline, plasma, serum prolactin levels, hormones, prolactin, ovary.
Belterman, R., T. Dorresteyn and M. van Wees (Editors) (2005). Asian Elephant Studbook Elephas Maximus. Europe Regional EAZA - EEP, Rotterdam Zoo: Rotterdam, 76 p.
Descriptors: Asian elephant, Elephas maximus, Europe, studbook.
Brown, J.L., F. Goritz, N. Pratt Hawkes, R. Hermes, M. Galloway, L.H. Graham, C. Gray, S.L. Walker, A. Gomez, and R. Moreland (2004). Successful artificial insemination of an Asian elephant at the National Zoological Park. Zoo Biology 23(1): 45-63. ISSN: 0733-3188.
NAL Call Number: QL77.5.Z6
Descriptors: Asian elephant, successful artificial insemination, National Zoo, reproduction.
Brown, J.L., D. Olson, M. Keele, and E.W. Freeman (2004). Survey of the reproductive cyclicity status of Asian and African elephants in North America. Zoo Biology 23(4): 309-321. ISSN: 0733-3188.
NAL Call Number: QL77.5.Z6
Descriptors: reproductive cyclicity, status, survey, African elephant, Asian elephant, North America.
Brown, J.L., S.L. Walker, and T. Moeller (2004). Comparative endocrinology of cycling and non-cycling Asian (Elephas maximus) and African (Loxodonta africana) elephants. General and Comparative Endocrinology 136(3): 360-70.
NAL Call Number: 444.8 G28
Abstract: Up to 14% of Asian and 29% of African elephants in captivity are not cycling normally or exhibit irregular cycles based on progestin profiles. To determine if ovarian acyclicity is related to other disruptions in endocrine activity, serum pituitary, thyroid, adrenal, and ovarian hormones in weekly samples collected for 6-25 months were compared between normal cycling (n=22 each species) and non-cycling (n=6 Asian; n=30 African) elephants. A subset of cycling females (n=4 Asian, 7 African) also were blood sampled daily during the follicular phase to characterize the peri-ovulatory period. In normal cycling females, two leutinizing hormone (LH) surges were observed 3 weeks apart during a normal follicular phase, with the second inducing ovulation (ovLH). Serum FSH concentrations were highest at the beginning of the non-luteal phase, declining 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. A species difference was noted in prolactin secretion. In the African elephant, prolactin was increased during the follicular phase, but in Asian elephants concentrations remained stable throughout the cycle. Patterns of thyroid hormones (thyroid-stimulating hormone, TSH; free and total thyroxine, T4; free and total triiodothyronine, T3) and cortisol secretion were not affected by estrous cycle stage or season in cycling elephants. In non-cycling elephants, there were no fluctuating patterns of LH, FSH, or prolactin secretion. Overall mean concentrations of all hormones were similar to those in cycling animals, with the exception of FSH, prolactin, and estradiol. Mean serum FSH concentrations were lower due to females not exhibiting normal cyclic increases, whereas serum estradiol was higher overall in most acyclic females. Prolactin concentrations were significantly increased in 11 of 30 non-cycling females, all of which were African elephants. In sum, while there were no consistent endocrine anomalies associated with ovarian acyclicity, hyperprolactinemia may be one cause of ovarian dysfunction. The finding of elevated estrogens in some acyclic females also deserves further investigation, especially determining how it relates to reproductive tract pathologies.
Descriptors: physiology, estrous cycle physiology, ovary physiology, blood, estradiol blood, estrous cycle blood, follicle stimulating hormone blood, hydrocortisone blood, luteinizing hormone blood, prolactin blood, seasons, species specificity, thyrotropin blood, thyroxine blood, triiodothyronine blood.
Brown, J.L. and T.B. Hildebrandt (2003). The science behind elephant artificial insemination. Biology of Reproduction 68(Supplement 1): 95-96. ISSN: 0006-3363.
NAL Call Number: QL876.B5
Descriptors: reproduction, artificial insemination, clinical techniques, captive breeding, sperm cryopreservation, transrectal ultrasound, diagnostic techniques, imaging, estrous cycle, ovulation, parturition, pregnancy.
Czekala, N.M., E.A. MacDonald, K. Steinman, S. Walker, N.W.I. Garrigues, D. Olson, and J.L. Brown (2003). Estrogen and LH dynamics during the follicular phase of the estrous cycle in the Asian elephant. Zoo Biology 22(5): 443-454. ISSN: 0733-3188.
NAL Call Number: QL77.5.Z6
Descriptors: Asian elephant, estrogen, LH, dynamics, follicular phase, estrus cycle, reproduction.
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.
Dahl, N.J., D.L. Schmitt, D.R. Blasko, and J.F. Roser (2004). A progesterone (p4) rise prior to and during the ovulatory luteinizing hormone (ovlh) peak may facilitate fertile ovulations in the African and Asian elephant (Loxodonta africana and Elephas maximus). Biology of Reproduction(Special Issue): 102-103. ISSN: 0006-3363.
NAL Call Number: QL876.B5
Descriptors: reproduction, infertility, disease, reproductive system disease, fertile, ovulation, progesterone rise, ovulatory luteinizing hormone, peak.
Dehnhard, M., J.M. Hatt, K. Eulenberger, A. Ochs, and G. Strauss (2003). Headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) for the determination of 5alpha-androst-2-en-17-one and -17beta-ol in the female Asian elephant: application for reproductive monitoring and prediction of parturition. Journal of Steroid Biochemistry and Molecular Biology 84(2-3): 383-91.
NAL Call Number: QD426.A1J6
Abstract: Asian elephants are not self-sustaining in captivity. The main reasons for this phenomenon are a low birth rate, an aging population, and poor calf-rearing. Therefore, it is essential that reproductive rates had to be improved and there is need for rapid quantitative measures to monitor reproductive functions focussing on estrous detection and the prediction of the period of parturition. The objective of this study was to develop a method which combines headspace solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) for analyses of 5alpha-androst-2-en-17beta-ol and -17-one to prognose estrous and to predict the period of parturition. SPME was carried out with a CTC Combi Pal system.The course of the luteal phase-specific substance 5alpha-androst-2-en-17beta-ol and -17-one followed a cyclic pattern in which the follicular and luteal phases could be clearly distinguished (mean estrous cycle length, 15+/-1.4 weeks). Based on daily urine samples, estrous prognosis might be possibly based on the initial 5alpha-androst-2-en-17beta-o1 increase at the end of the follicular phase. Parturition prognosis was performed in three elephant cows based on the 5alpha-androst-2-en-17beta-o1 drop to baseline levels 5-4 days prior parturition. Experiments revealed that 5alpha-androst-3alpha-ol-17-one and probably 5alpha-androst-3alpha-ol-17beta-ol are generated from sulfate conjugates by a thermal process.
Descriptors: androstane 3,17 diol blood, androsterone blood, chemistry, clinical methods, mass fragmentography methods, parturition blood, chromatography, gas, estrous cycle, pregnancy, animal blood, temperature, time factors.
Duer, C., M. Carden, and T. Tomasi (2007). Detection of fetal gender differences in maternal serum progesterone concentrations of Asian elephants (Elephas maximus). Animal Reproduction Science 97(3/4): 278-283. ISSN: 0378-4320.
Abstract: Previous studies have analysed total testosterone concentrations in maternal serum for a reliable method of fetal gender determination in Asian elephants (Elephas maximus). The present study investigated the possibility that progesterone concentrations in maternal serum may reflect these testosterone patterns. Weekly serum samples were collected from 17 pregnancies in captive Asian elephants and analysed via radioimmunioassy (RIA) for progesterone concentrations. Nine and eight cows carried male and female calves, respectively. Mean progesterone concentrations in maternal serum of elephants carrying male calves were greater than in those carrying female calves (P<0.01). Mean progesterone concentrations (based on 5-week means) in maternal serum were greater at weeks 20-55 (P<0.01) and 60-65 (P<0.05) for elephants carrying male calves. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, pregnancy, progesterone, sex determination, sex differences, testosterone.
Freeman, E.W., E. Weiss, and J.L. Brown (2004). Examination of the interrelationships of behavior, dominance status, and ovarian activity in captive Asian and African elephants. Zoo Biology 23(5): 431-448. ISSN: 0733-3188.
NAL Call Number: QL77.5.Z6
Descriptors: ovarian activity, Asian elephants, African elephants, dominance status, behavior, interrelationships.
Graham, L.H., J. Bando, C. Gray, and M.M. Buhr (2004). Liquid storage of Asian elephant (Elephas maximus) sperm at 4 degrees C. Animal Reproduction Science 80(3-4): 329-40.
NAL Call Number: QP251.A5
Abstract: The Asian elephant (Elephas maximus) population in the wild has been in decline for several decades and breeding in captivity has not been self-sustaining. The use of artificial insemination (AI) can help overcome many of the difficulties associated with breeding elephants in captivity; however, the ability to store semen for extended periods of time is critical to the successful application of AI to elephants. The objective of the present study was to assess the effects of four different semen extenders and the presence of egg yolk on the viability and motility of Asian elephant semen stored at 4 degrees C. High quality ejaculates (n=4) were collected from two Asian elephant bulls by rectal massage. Aliquots of each ejaculate were extended in four different diluents (Beltsville thawing solution (BTS); Tris-citric acid (TCA)/fructose-based; Beltsville F5 (BF5); dextrose-supplemented phosphate-buffered saline (PBS)) with or without egg yolk then cooled and stored at 4 degrees C. The percentages of viable (viability) and motile (motility) sperm were evaluated at 8, 24 and 48 h following collection. The addition of egg yolk significantly reduced the percentage loss in viability from initial collection to 48 h compared to extenders without egg yolk (17.0 +/- 8.2 versus 32.6 +/- 8.9 decline in percent viable sperm in the population, respectively; P<0.05). Extender and egg yolk affected (P<0.005) total motility and percent progressively motile sperm at all evaluation times during incubation. TCA + egg yolk maintained higher (P<0.05) levels of progressive motility compared to other extenders supplemented with egg yolk. These results indicate that Asian elephant semen extended in TCA diluent supplemented with egg yolk can maintain at least 50% viability and motility when stored at 4 degrees C for 48 h.
Descriptors: semen preservation, spermatozoa physiology, breeding, buffers, cell survival, cold, egg yolk, ejaculation, artificial insemination, semen preservation methods, sperm motility, tissue and organ harvesting methods.
Graham, L.H., C. Gray, and M.M. Buhr (2004). Influence of cryoprotectant type and concentration on post-thaw characteristics of cryopreserved Asian elephant (Elephas maximus) semen. Biology of Reproduction(Special Issue): 236. ISSN: 0006-3363.
NAL Call Number: QL876.B5
Descriptors: semen, cryopreservation, Asian elephant, post thaw, characteristics, cyroprotectant, influence.
Hama, N., A. Yamada, A. Noda, K. Murata, Y. Shimada, M. Ashida, K.M.Y. Ishikawa, and K. Okuno (2003). Serum hormonal changes in a female Asian elephant (Elephas maximus) with stillbirth. Japanese Journal of Zoo and Wildlife Medicine 8(2): 109-113. ISSN: 1342-6133.
Descriptors: Asian elephant, female, hormonal changes, seasonal, stillbirth, serum, progesterone, estradiol, prolactin, radioimmunoassay, RIA.
Language of Text: Japanese, with English summary.
Hermes, R., B. Behr, T.B. Hildebrandt, S. Blottner, B. Sieg, A. Frenzel, A. Knieriem, J. Saragusty, and D. Rath (2009). Sperm sex-sorting in the Asian elephant (Elephas maximus). Animal Reproduction Science 112(3/4): 390-396. ISSN: 0378-4320.
Abstract: In captive Asian elephants, there is a strong need for production of female offspring to enhance reproduction, counter premature aging processes in female animals and reduce challenging management situations derived from husbandry of several bulls in one institution. Artificial insemination of flow cytometrically sex-sorted spermatozoa offers the possibility to predetermine the sex of offspring with high accuracy. The aims of this study were to determine a suitable semen extender and basic parameters for flow cytometrical sex-sorting of Asian elephant spermatozoa. In total 18 semen samples were collected by manual rectal stimulation from one bull. Sperm quality parameters and sex sortability of spermatozoa were evaluated after dilution in three semen extenders (MES-HEPES-skim milk, MES-HEPES, TRIS-citric acid) and DNA staining. MES-HEPES-skim milk was the only semen extender found suitable to sex Asian elephant spermatozoa. From 18 ejaculates collected, 12 were successfully sorted with a purity of 94.5+or-0.7% at an average sort rate of 1945.5+or-187.5 spermatozoa per second. Sperm integrity, progressive and total motility were 42.6+or-3.9%, 48.1+or-3.3%, 59.4+or-3.8% after DNA labelling, and 64.8+or-3.2%, 58.0+or-5.0%, 70.8+or-4.4% after sorting, respectively. After liquid storage of sorted spermatozoa for 12 h at 4 degrees C, sperm integrity, progressive and total motility were 46.4+or-5.2%, 32.2+or-4.2% and 58.2+or-3.9%, respectively. The obtained results provide a promising base to inseminate Asian elephants with sexed semen. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, artificial insemination, bulls, semen, sexual reproduction, spermatozoa, storage.
Kirtland, J. (2003). Dreams and false promises: Asian elephant reproduction in North America. American Zoo and Aquarium Association Annual Conference Proceedings 2003: 49-54.
NAL Call Number: QL76.5.U6A472
Descriptors: Asian elephant, Elephas maximus, breeding programs, North America, reproduction.
Lazar, J., L.E. Rasmussen, D.R. Greenwood, I.S. Bang, and G.D. Prestwich (2004). Elephant albumin: a multipurpose pheromone shuttle. Chemistry and Biology 11(8): 1093-100.
Abstract: (Z)-7-dodecenyl acetate (Z7-12:Ac) is present in the urine of female Asian elephants (Elephas maximus) approaching ovulation and functions as a female-to-male sex pheromone. Here we show that a significant fraction of the pheromone in the urine is bound to a protein, elephant serum albumin (ESA), and provide evidence for key physiological functions of urinary ESA. Our biochemical and behavioral experiments suggest a three-fold role of ESA in pheromone signaling: (1) transporting Z7-12:Ac from serum into urine; (2) extending the presence of the pheromone in the environment without hampering detection; and (3) targeting pheromone delivery to chemosensory organs through localized release of the ligand induced by a pH change. The exploitation of albumin in pheromone transport clearly distinguishes the elephant from other mammals studied, and complements the uniqueness of elephant anatomy, physiology, and behavior.
Descriptors: acetates metabolism, albumins metabolism, pheromones metabolism, acetates urine, albumins chemistry, albumins genetics, biological availability, biological transport, cloning, molecular, hydrogen ion concentration, molecular structure, pheromones urine, substrate specificity, time factors, urine chemistry.
Meyer, J.M., S.L. Walker, E.W. Freeman, B.G. Steinetz, and J.L. Brown (2004). Species and fetal gender effects on the endocrinology of pregnancy in elephants. General and Comparative Endocrinology 138(3): 263-270.
NAL Call Number: 444.8 G28
Abstract: Quantitative and temporal progestin profiles vary during gestation in the elephant, sometimes making it difficult to determine if a pregnancy is progressing normally. The aim of the present study was to determine if circulating progestin variability was related to species or fetal gender effects. A similar comparison also was conducted for secretory profiles of prolactin, relaxin, and cortisol. Overall mean progestin concentrations during gestation in Asian (n = 19) and African (n = 8) elephants were similar; however, the temporal profiles differed (P < 0.001). Concentrations were higher in African elephants during the first half of pregnancy, but then declined to levels below those observed in Asian elephants (P < 0.05). There also was a fetal gender effect in Asian, but not African elephants. Progestin concentrations were higher in Asian cows carrying male calves (n = 9) as compared to those carrying females (n = 10) (P < 0.001). Overall prolactin concentrations were higher in Asian than in African elephants between 8 and 15 months of gestation ( P< 0.001). There were no species differences in the secretory patterns of relaxin. Cortisol was relatively stable until the end of gestation when significant surges were observed, mainly between 8 and 11 days before parturition, and again on the day of birth. In sum, a comparison of progestin patterns between Asian and African elephants identified notable differences related to species and fetal gender. A role for cortisol in the initiation of parturition also was inferred from these data. From a practical standpoint, understanding the factors affecting gestational hormone characteristics and recognizing what the species differences are will help ensure that data used in diagnosing and monitoring elephant pregnancies are properly interpreted.
Descriptors: blood, embryology, hydrocortisone in blood, maternal fetal exchange physiology, pregnancy, progestins in blood, analysis of variance, fetus, prolactin in blood, relaxin in blood, sex factors, species specificity.
Oliveira, C.A., E.C.G. Felippe, and M.O.M. Chelini (2008). Serum cortisol and progestin concentrations in pregnant and non-pregnant Asian elephants (Elephas maximus). Research in Veterinary Science 84(3): 361-363. ISSN: 0034-5288.
Abstract: Blood samples were collected during the estrous cycle (n=3), throughout gestation (n=3), and during the periparturient period (n=11) to assess serum concentrations of cortisol in pregnant and non-pregnant Asian elephants whose reproductive status was being monitored by serum progestin determination. While serum cortisol concentrations remained constant throughout gestation, progestin concentrations decreased significantly (p<0.05) in the second half of pregnancy, declining to undetectable levels by 3 days before calving. During the non-luteal phase of the estrous cycle serum progestins varied from undetectable levels to 100 pg/ml (53+or-10.7 pg/ml) then increased steadily during the luteal phase (322+or-207.5 pg/ml). There were no significant differences between serum cortisol concentrations during the luteal and those of the non-luteal phase (p>0.05). The mean cortisol concentration during the estrous cycle was about twice that during pregnancy (p>0.05). No substantial changes in maternal cortisol were found during the course of pregnancy or the periparturient period. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, blood chemistry, circus animals, hydrocortisone, estrous cycle, pregnancy, progesterone.
Portas, T.J., B.R. Bryant, F. Goritz, R. Hermes, T. Keeley, G. Evans, W.M.C. Maxwell, and T.B. Hildebrandt (2007). Semen collection in an Asian elephant (Elephas maximus) under combined physical and chemical restraint. Australian Veterinary Journal 85(10): 425-427. ISSN: 1751-0813.
Abstract: This article describes technique of manual stimulation for semen collection in a captive 50-year-old male Asian elephant (Elephas maximus) in New South Wales, Australia, physically restrained in a restraint chute and anesthetized with a combination of xylazine (Xylazil-100) and butorphanol (Torbugesic). This technique was effective for semen collection on the same animal for three occasions, but cannot be recommended for routine and repeated use due to the potential risk associated with anesthesia. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, anesthesia, anesthetics, butorphanol, restraint of animals, semen, techniques, xylazine, zoo animals.
Rasmussen, L., V. Krishnamurthy, and R. Sukumar (2005). Behavioural and chemical confirmation of the preovulatory pheromone, (Z) -7-dodecenyl acetate, in wild Asian elephants: its relationship to musth. Behaviour 142(3): 351-396. ISSN: 0005-7959.
NAL Call Number: 410 B393
Descriptors: Asian elephant, Elephas maximus, age, reproductive behavior, musth, mating strategies, female preovulatory hormone, pheromones, preovulatory urinary hormone, social behavior, India, preovulatory hormone identification, male chemosensory responses.
Rees, P.A. (2004). Some preliminary evidence of the social facilitation of mounting behavior in a juvenile bull Asian elephant (Elephas maximus). Journal of Applied Animal Welfare Science 7(1): 49-58.
NAL Call Number: HV4701.J68
Abstract: This study recorded sexual behavior within a captive herd of 8 Asian elephants for approximately 230 hr on 50 days over a period of 10 months. The study observed a single adult and a single juvenile bull mounting cows more than 160 times. When the juvenile bull was between 4 years, 2 months and 4 years, 8 months old, he exhibited mounting behavior only on days when adult mounting occurred. Adult mounting always occurred first. Beyond the age of 4 years, 8 months, the juvenile bull exhibited spontaneous mounting behavior in the absence of adult mounting. This suggests that mounting behavior may develop because of social facilitation. Determining the significance of the presence of sexually active adults in the normal development of sexual behavior in juveniles will require further studies. Encouraging the establishment of larger captive herds containing adults and calves of both sexes-if their presence is important-would improve the welfare of elephants in zoos and increase their potential conservation value.
Descriptors: sex behavior, social environment, zoo animals.
Sa Ardrit, M., J. Saikhun, N. Thongtip, M. Damyang, S. Mahasawangkul, T. Angkawanish, S. Jansittiwate, T. Faisaikarm, Y. Kitiyanant, K. Pavasuthipaisit, and A. Pinyopummin (2006). Ultrastructural alterations of frozen-thawed Asian elephant (Elephas maximus) spermatozoa. International Journal of Andrology 29(2): 346-52.
NAL Call Number: QP251.I55
Abstract: Intact plasma and acrosome membranes and functional mitochondria following cryopreservation are important attributes for the fertilizing ability of spermatozoa. In the present study, functional and ultrastructural changes of Asian elephant spermatozoa after cryopreservation either in TEST + glycerol or HEPT + dimethyl sulphoxide (DMSO) were evaluated by fluorescent techniques and electron microscopy. Sperm frozen in TEST + glycerol had higher proportion of sperm with intact plasma (49.1 +/- 9.2% vs. 30.9 +/- 3.9%) and acrosomal (53.7 +/- 4.9% vs. 35.8 +/- 6.1%) membranes, as well as active mitochondria (57.0 +/- 7.2% vs. 42.0 +/- 5.0%) than those cryopreserved in HEPT + DMSO. The results obtained from electron microscopy were similar to those obtained by fluorescence microscopy. The percentage of normal spermatozoa was higher when spermatozoa were frozen in TEST + glycerol than those frozen in HEPT + DMSO (31.8 +/- 5.6 vs. 28.5 +/- 6.4). The ultrastructural alterations revealed by transmission electron microscopy could be classified as (i) distension of plasma membrane, while the acrosome was swollen; (ii) disruption or loss of plasma membrane, while acrosome was swollen with distended outer acrosomal membrane; (iii) disruption or loss of plasma and outer acrosomal membrane with leakage of acrosome content; (iv) extensive vesiculation of plasma and outer acrosomal membrane and leakage of acrosome content; (v) a complete loss of both plasma membrane and outer acrosomal membrane; and (vi) swelling of mitochondria. These findings suggest that the freezing and thawing procedure caused structural damage to elephant spermatozoa, especially in the plasma membrane, acrosome and mitochondria. Fluorescence and electron microscopic evaluations are potentially a powerful tool in the analysis of elephant spermatozoa after freezing and thawing.
Descriptors: Asian elephant, spermatozoa, frozen, thawed, ultrastructural, alterations, cryopreservation, fertilizing ability.
Saragusty, J., T.B. Hildebrandt, B. Behr, A. Knieriem, J. Kruse, and R. Hermes (2009). Successful cryopreservation of Asian elephant (Elephas maximus) spermatozoa. Animal Reproduction Science 115(1/4): 255-266. ISSN: 0378-4320.
Abstract: Reproduction in captive elephants is low and infant mortality is high, collectively leading to possible population extinction. Artificial insemination was developed a decade ago; however, it relies on fresh-chilled semen from just a handful of bulls with inconsistent sperm quality. Artificial insemination with frozen-thawed sperm has never been described, probably, in part, due to low semen quality after cryopreservation. The present study was designed with the aim of finding a reliable semen freezing protocol. Screening tests included freezing semen with varying concentrations of ethylene glycol, propylene glycol, trehalose, dimethyl sulfoxide and glycerol as cryoprotectants and assessing cushioned centrifugation, rapid chilling to suprazero temperatures, freezing extender osmolarity, egg yolk concentration, post-thaw dilution with cryoprotectant-free BC solution and the addition of 10% (v/v) of autologous seminal plasma. The resulting optimal freezing protocol uses cushioned centrifugation, two-step dilution with isothermal 285 m Osm/kg Berliner Cryomedium (BC) with final glycerol concentration of 7% and 16% egg yolk, and freezing in large volume by the directional freezing technique. After thawing, samples are diluted 1:1 with BC solution. Using this protocol, post-thaw evaluations results were: motility upon thawing: 57.2+or-5.4%, motility following 30 min incubation at 37 degrees C: 58.5+or-6.0% and following 3 h incubation: 21.7+or-7.6%, intact acrosome: 57.1+or-5.2%, normal morphology: 52.0+or-5.8% and viability: 67.3+or-6.1%. With this protocol, good quality semen can be accumulated for future use in artificial inseminations when and where needed. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, artificial insemination, bulls, chilling, cryopreservation, cryoprotectants, dimethyl sulfoxide, egg yolk, eggs, endangered species, ethylene glycol, freezing, gametes, genomes, glycerol, incubation, infant mortality, insemination, mortality, propylene glycol, seminal plasma, sexual reproduction, spermatozoa, thawing.
Saragusty, J., T.B. Hildebrandt, Y. Natan, R. Hermes, S. Yavin, F. Goeritz, and A. Arav (2005). Effect of egg-phosphatidylcholine on the chilling sensitivity and lipid phase transition of Asian elephant (Elephas maximus) spermatozoa. Zoo Biology 24(3): 233-245. ISSN: 0733-3188.
NAL Call Number: QL77.5.Z6
Descriptors: semen extenders, cooling, liposomes artificial, cryopreservation, cryoprotectants, spermatazoa.
Saragusty, J., T.B. Hildebrandt, B. Behr, A. Knieriem, J. Kruse, and R. Hermes (2009). Successful cryopreservation of Asian elephant (Elephas maximus) spermatozoa. Animal Reproduction Science 115(1-4): 255-266. ISSN: 0378-4320.
NAL Call Number: QP251.A5
Abstract: Reproduction in captive elephants is low and infant mortality is high, collectively leading to possible population extinction. Artificial insemination was developed a decade ago; however, it relies on fresh-chilled semen from just a handful of bulls with inconsistent sperm quality. Artificial insemination with frozen-thawed sperm has never been described, probably, in part, due to low semen quality after cryopreservation. The present study was designed with the aim of finding a reliable semen freezing protocol. Screening tests included freezing semen with varying concentrations of ethylene glycol, propylene glycol, trehalose, dimethyl sulfoxide and glycerol as cryoprotectants and assessing cushioned centrifugation, rapid chilling to suprazero temperatures, freezing extender osmolarity, egg yolk concentration, post-thaw dilution with cryoprotectant-free BC solution and the addition of 10% (v/v) of autologous seminal plasma. The resulting optimal freezing protocol uses cushioned centrifugation, two-step dilution with isothermal 285mOsm/kg Berliner Cryomedium (BC) with final glycerol concentration of 7% and 16% egg yolk, and freezing in large volume by the directional freezing technique. After thawing, samples are diluted 1:1 with BC solution. Using this protocol, post-thaw evaluations results were: motility upon thawing: 57.2pl5.4%, motility following 30min incubation at 37pC: 58.5pl6.0% and following 3h incubation: 21.7pl7.6%, intact acrosome: 57.1pl5.2%, normal morphology: 52.0pl5.8% and viability: 67.3pl6.1%. With this protocol, good quality semen can be accumulated for future use in artificial inseminations when and where needed. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, spermatozoa, cryopreservation, artificial insemination, reproduction.
Slade, B.E., B. Schulte, and L.E.L. Rasmussen (2003). Oestrous state dynamics in chemical communication by captive female Asian elephants. Animal Behaviour 65(4): 813-819. ISSN: 0003-3472.
NAL Call Number: Film S-1802
Descriptors: reproductive status, urine, estrus, female, Asian elephants, chemical communication, social group dynamics, chemosensory responses.
Slade Cain, B.E., L.E.L. Rasmussen, and B.A. Schulte (2008). Estrous state influences on investigative, aggressive, and tail flicking behavior in captive female Asian elephants. Zoo Biology 27(3): 167-180. ISSN: 0733-3188.
NAL Call Number: QL77.5.Z6
Abstract: Females of species that live in matrilineal hierarchies may compete for temporally limited resources, yet maintain social harmony to facilitate cohesion. The relative degree of aggressive and nonaggressive interactions may depend on the reproductive condition of sender and receiver. Individuals can benefit by clearly signaling and detecting reproductive condition. Asian elephants (Elephas maximus) live in social matrilineal herds. Females have long estrous cycles (14-16 weeks) composed of luteal (8-12 weeks) and follicular (4-8 weeks) phases. In this study, we observed the behavior of four captive Asian elephant females during multiple estrous cycles over 2 years. We evaluated whether investigative, aggressive, and tail flicking behaviors were related to reproductive condition. Investigative trunk tip contacts showed no distinct pattern by senders, but were more prevalent toward female elephants that were in their follicular compared with their luteal phase. The genital area was the most frequently contacted region and may release reproductively related chemosignals. Aggression did not differ significantly with estrus; however, rates of aggression were elevated when senders were approaching ovulation and receivers were in the luteal phase. Females in the follicular phase may honestly advertise their condition. Contacts by conspecifics may serve to assess condition and reduce aggression. A behavior termed "tail flicking" was performed mainly during the mid-follicular phase when estrogen and luteinizing hormone levels are known to spike. Tail flicking may disperse chemical signals in urine or mucus as well as act as a tonic signal that could provide a means of anticipating forthcoming ovulation by elephants and also for human observers and caretakers. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, estrous cycle, estrus, ovulation, animal behavior, social behavior, aggression, tail, touch, animal communication, zoo animals, follicular phase, luteal phase, female behavior, investigative behavior, tactile behavior.
Teng MingSheng, Yang XiaoLi, and Wu DengHu (2003). Characteristics of reproductive biology of Asian elephants. Chinese Journal of Zoology 38(6): 86-90. ISSN: 0250-3263.
NAL Call Number: QL1.T8
Descriptors: reproductive biology, characteristics, Asian elephant, mating, estrus, parturition, pregnancy, reproduction, Elephas maximus, fetuses, gestation.
Language of Text: Chinese, with English summary.
Thitaram, C., J.L. Brown, P. Pongsopawijit, S. Chansitthiwet, W. Wongkalasin, P. Daram, R. Roongsri, A. Kalmapijit, S. Mahasawangkul, and S. Rojansthien (2008). Seasonal effects on the endocrine pattern of semi-captive female Asian elephants (Elephas maximus): Timing of the anovulatory luteinizing hormone surge determines the length of the estrous cycle. Theriogenology 69(2): 237-244. ISSN: 0093-691X.
NAL Call Number: QP251.A1T5
Abstract: Better breeding strategies for captive Asian elephants in range countries are needed to increase populations; this requires a thorough understanding of their reproductive physiology and factors affecting ovarian activity. Weekly blood samples were collected for 3.9 years from 22 semi-captive female Asian elephants in Thai elephant camps to characterize LH and progestin patterns throughout the estrous cycle. The duration of the estrous cycle was 14.6 pl 0.2 weeks (mean pl S.E.M.; n = 71), with follicular and luteal phases of 6.1 pl 0.2 and 8.5 pl 0.2 weeks, respectively. Season had no significant effect on the overall length of the estrous cycle. However, follicular and luteal phase lengths varied among seasons and were negatively correlated (r = -0.658; P < 0.01). During the follicular phase, the interval between the decrease in progestin concentrations to baseline and the anovulatory LH (anLH) surge varied in duration (average 25.9 pl 2.0 days, range 7-41, n = 23), and was longer in the rainy season (33.4 pl 1.8 days, n = 10) than in both the winter (22.2 pl 4.5 days, n = 5; P < 0.05) and summer (18.9 pl 2.6 days, n = 8; P < 0.05). By contrast, the interval between the anLH and ovulatory LH (ovLH) surge was more consistent (19.0 pl 0.1 days, range 18-20, n = 14). Thus, seasonal variation in estrous cycle characteristics were mediated by endocrine events during the early follicular phase, specifically related to timing of the anLH surge. Overall reproductive hormone patterns in Thai camp elephants were not markedly different from those in western zoos. However, this study was the first to more closely examine how timing of the LH surges impacted estrous cycle length in Asian elephants. These findings, and the ability to monitor reproductive hormones in range countries (and potentially in the field), should improve breeding management of captive and semi-wild elephants. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, anovulation, luteinizing hormone, progestational hormones, hormone secretion, temporal variation, seasonal variation, estrous cycle, duration , Thailand, follicular phase, luteal phase.
Thitaram, C., P. Pongsopawijit, S. Chansitthiwet, J.L. Brown, K. Nimtragul, K. Boonprasert, P. Homkong, S. Mahasawangkul, S. Rojanasthien, B. Colenbrander, G.C. van derWeijden, and F.J.C.M. van Eerdenburg (2009). Induction of the ovulatory LH surge in Asian elephants (Elephas maximus): a novel aid in captive breeding management of an endangered species. Reproduction, Fertility and Development 21(5): 672-678. ISSN: 1031-3613.
Abstract: A unique feature of the reproductive physiology of Asian elephants (Elephas maximus) is the occurrence of two LH surges before ovulation, instead of one. An anovulatory LH (anLH) surge, the function of which is unknown, occurs consistently 3 weeks before the ovulatory LH (ovLH) surge that induces ovulation. Thus, the ability to induce an ovLH surge would be useful for scheduling natural mating or artificial insemination. The present study tested the efficacy of a gonadotrophin-releasing hormone agonist (GnRH-Ag) to induce LH surges during the follicular phase of the estrous cycle, which resulted in varied LH responses, but generally none were as high as previously documented natural surges. Thus, for the ovulation-induction trials, nine females were administered 80 micro g GnRH-Ag intravenously at three time periods during the estrous cycle, namely the anovulatory follicular phase, the ovulatory follicular phase and the luteal phase. During the late anovulatory follicular phase, nine of 10 females (90%) responded with an immediate LH surge followed 15-22 days later by an ovLH surge or a post-ovulatory increase in progestagens. In contrast, despite responding to the GnRH-Ag with an immediate increase in LH, none of the females treated during other periods of the estrous cycle exhibited subsequent ovLH surges. One cow got pregnant from natural mating following the induced ovLH surge. In conclusion, ovLH induction is possible using a GnRH-Ag, but only during a specific time of the anovulatory follicular phase. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, animal breeding, breeding programmes, endangered species, gonads, estrous cycle, Hollyhock leaf crumple virus.
Thitaram, C., S. Chansitthiwet, P. Pongsopawijit, J.L. Brown, W. Wongkalasin, P. Daram, R. Roongsri, A. Kalmapijit, S. Mahasawangkul, S. Rojanasthien, B. Colenbrander, G.C. van der Weijden, and F.J.C.M. van Eerdenburg (2009). Use of genital inspection and female urine tests to detect estrus in captive Asian elephants. Animal Reproduction Science 115(1-4): 267-278. ISSN: 0378-4320.
NAL Call Number: QP251.A5
Abstract: Captive Asian elephant (Elephas maximus) populations are decreasing due to low birth rates compared to wild elephants. Improving estrous detection in female elephants is required to ensure successful mating in captive and semi-captive herds. Responsive behaviours of eight semi-captive bull elephants to the uro-genital area (genital inspection test) or urinary pheromones (urine test) of 14 female elephants throughout the estrous cycle were evaluated. Weekly blood samples were collected for 27 consecutive months (14 months for the genital inspection test and 13 months for the urine test) from female elephants to characterize the patterns of circulating progestagen. Responsive behaviours of bulls were compared between females in the follicular versus the luteal phase of the cycle. The sensitivity and specificity of the genital inspection test were 65% and 68%, while those of the urine test were 52% and 61%, respectively. The bulls showed significantly higher genital inspection, flehmen from genital area and trunk on back behaviours during the genital inspection test, and flehmen behaviours during the urine test in oestrous than in non-estrous females. In sum, this study showed that monitoring sexual behaviours of Asian elephant bulls towards females or their urine can be used to detect the estrous period. Although the sensitivity and specificity of both tests were not as high as expected, still, these methods appear to be more efficient at detecting estrous than traditional methods based on mahout estimations of female receptivity. The use of genital inspection and urine tests may lead to more successful matings and thus to creating self-sustaining populations of captive elephants in range countries. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, genital inspection, urine tests, estrus detection, female, captive, matings.
Thongtip, N., M. Damyang, S. Mahasawangkul, A. Kongsila, T. Angkawanich, S. Jansittiwate, C. Thitaram, and P. Phongsopawijit (2003). Frozen semen artificial insemination in Asian elephants (Elephas maximus) using endoscope and ultrasound guide. Proceedings of 41st Kasetsart University Annual Conference, Subject: Animals and Veterinary Medicine,February 3, 2003-February 7, 2003, Bangkok, Thailand: Kasetsart University, Bangkok, Thailand, p. 652-657.
Descriptors: Asian elephant, frozen semen, artificial insemination, endoscopy, cervix, thawed semen, ultrasonography, Elephas maximus.
Language of Text: Thai, with English summary.
Thongtip, N., J. Saikhun, M. Damyang, S. Mahasawangkul, P. Suthunmapinata, M. Yindee, A. Kongsila, T. Angkawanish, S. Jansittiwate, and W. Wongkalasin (2004). Evaluation of post-thaw Asian elephant (Elephas maximus) spermatozoa using flow cytometry: the effects of extender and cryoprotectant. Theriogenology 62(3-4): 748-760. ISSN: 0093-691X.
NAL Call Number: QP251.A1T5
Abstract: Although the development of semen cryopreservation in the African elephants (Loxodonta africana) has been accomplished, effective procedures for cryopreservation of Asian elephant (Elephas maximus) spermatozoa have not been established. In the present study, we investigate the freezing methods for conservation of Asian elephant spermatozoa under field conditions and identify the most suitable freezing protocols which provide acceptable post-thaw semen quality. Semen was collected from two Asian elephant bulls (EM1 and EM2, 10 ejaculates from each bull) by manual manipulation and were assessed for volume, pH, sperm cell concentration, and progressive motility. Eight out of 20 ejaculates were of acceptable quality (progressive motility greater than or equal to 60%), and were used for cryopreservation studies. Semen were frozen in TEST+glycerol, TEST+DMSO, HEPT+glycerol, or HEPT+DMSO. The post-thaw progressive sperm motilities were assessed, and sperm cells were stained with PI and FITC-PNA for membrane and acrosomal integrity assessment using flow cytometry. Post-thaw progressive motility of spermatozoa (EM1: 42.0½4.3%; EM2: 26.0½17.3%) and the percentage of membrane and acrosome intact spermatozoa (EM1: 55.5½8.1%; EM2: 46.3½6.4%) cryopreserved in TEST+glycerol were significantly higher than (P<0.05) those frozen in the other medium investigated choices for cryopreservation of Asian elephant spermatozoa. The data support the use of TEST+glycerol as an acceptable cryopreservation media of Asian elephant semen for the establishment of sperm banks.
Descriptors: Elephas maximus, spermatozoa, cryopreservation, semen extenders, cryoprotectants, flow cytometry, freezing, thawing, sperm motility, glycerol, dimethyl sulfoxide, plasma membrane, membrane permeability, acrosome reaction, male fertility, membrane integrity.
Thongtip, N., J. Saikhun, S. Mahasawangkul, K. Kornkaewrat, P. Suthanmapinanh, and A. Pinyopummin (2008). Effect of pentoxifylline on the motility characteristics and viability of spermatozoa in Asian elephants (Elephas maximus) with low semen quality. Thai Journal of Veterinary Medicine 38(3): 37-45. ISSN: 0125-6491.
Abstract: To investigate the effects of pentoxifylline (PTX) to enhance the motility and fertilization capacity of semen samples with the low-motile sperm in Asian elephants (Elephas maximus), 14 semen collection attempts in 9 elephant bulls in Thailand by manual stimulation were undertaken and eleven ejaculates fitted the criteria of investigation (0-30% motility). These were divided into poor-motile (0-9% motility) and low-motile (10-30% motility) sperm groups. Fresh semen samples were divided as a control group and 3 experimental groups that were supplemented with PTX at a final concentration of 0.5, 1.0 and 2.0 mg/ml. The semen samples were incubated at 37 degrees C for 15 and 30 min and stained with VIADENT media for viability assessment. Sperm motility and viability were tested using computer-assisted semen analysis. PTX added to the semen did not significantly improve the percentage of the total and progressive motility, motility characteristics and viability of sperm in either the poor-or low-motile groups. However, at 30 min, in the low-motile sperm group, PTX treatment maintained the percentage of total and progressive motility, path velocity and progressive velocity at a higher level than the control group. The present study indicates that PTX added to low motility semen does not increase elephant semen quality. However, it may partially have a tendency to maintain sperm motility and sperm movement characteristics. Reproduced with Permission from CAB Abstracts.
Descriptors: Asian elephant, Elephas maximus, male fertility, motility, pentoxifylline, semen, semen characters, spermatozoa, velocity.
Language of Text: Thai.
Vandebona, H., N.C.W. Goonesekere, W.D. Ratnasooriya, J. Alahakoon, and M.B. Gunasekera (2005). Using dna fingerprinting to establish paternity of Asian elephants, Elephas maximus, born at Pinnawela Elephant Orphanage, Sri Lanka. Annales Academiae Regiae Scientiarum Upsaliensis 39: 214-221. ISSN: 0504-0736.
Descriptors: Asian elephants, paternity identification, DNA fingerprinting, blood samples, genetic diversity, breeding programs, estrus, mating, Sri Lanka.
Yon, L., S. Kanchanapangka, N. Chaiyabutr, S. Meepan, F.Z. Stanczyk, N. Dahl, and B. Lasley (2007). A longitudinal study of LH gonadal and adrenal steroids in four intact Asian bull elephants (Elephas maximus) and one castrate African bull (Loxodonta africana) during musth and non-musth periods. General and Comparative Endocrinology 151(3): 241-245. ISSN: 0016-6480; Online: 1095-6840.
Descriptors: African elephant, Loxodonta africana, Asian elephant, Elephas maximus, endocrine system, reproduction, castration, musth cycle.