Comparative Reproductive Biology of Elephants

Brown, Janine L.

doi:10.1007/978-1-4939-0820-2_8

Cited by 32 publications

(29 citation statements)

References 154 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ovarian acyclicity Reproductive problems of captive elephants are well documented and for African elephants, in particular, a high rate of ovarian acyclicity across age categories thwarts population sustainability (Brown, ). In North America, 52% of female African elephants exhibit abnormal cycles, with 38% not cycling at all (Brown et al ., ).…”

Section: Reproductionmentioning

confidence: 99%

Zoo elephant research: contributions to conservation of captive and free‐ranging species

Bechert

Brown

Dierenfeld

et al. 2019

International Zoo Yearbook

View full text Add to dashboard Cite

African elephants Loxodonta africana and Asian elephants Elephas maximus are not thriving in many captive settings and are threatened throughout their native ranges. Many zoos support in situ conservation projects and provide opportunities to conduct ex situ research in controlled settings with comparably approachable animals. Zoo elephant projects may facilitate fieldwork with free‐ranging elephants (e.g. development of non‐invasive sampling and analytical tools), which may then also improve the husbandry of elephants in human care. Free‐ranging elephants also benefit from drug therapies and veterinary care when they are orphaned, kept as working elephants or brought in as rehabilitation cases – especially as human–elephant conflicts become more common as a result of ever‐expanding human populations. Much has been learned about the basic biology and husbandry needs of elephants but, often, the more we learn, the more questions arise. There are physiological differences between African and Asian elephants, and this should affect the management of these animals. This paper will provide brief overviews of the current state of knowledge regarding the pharmacology, nutrition, reproduction, sensory biology and diseases (primarily elephant endotheliotropic herpesvirus infections) relevant to elephants with recommendations for future research.

show abstract

Section: Reproductionmentioning

confidence: 99%

Zoo elephant research: contributions to conservation of captive and free‐ranging species

Bechert

Brown

Dierenfeld

et al. 2019

International Zoo Yearbook

View full text Add to dashboard Cite

show abstract

“…Captive propagation is one strategy to ensure species survival [ 3 ], especially when conducted in range countries [ 4 ]. However, many Asian elephant ( Elephas maximus ) populations ex situ are not self-sustaining due to poor reproduction [ 5 ] or health problems [ 6 – 8 ].…”

Section: Introductionmentioning

confidence: 99%

Body condition and adrenal glucocorticoid activity affects metabolic marker and lipid profiles in captive female elephants in Thailand

et al. 2018

Self Cite

View full text Add to dashboard Cite

Studies in western zoo elephants have found relationships between body condition and physiological function, and identified mitigating management strategies to optimize health and welfare. A similar methodological approach was used in this study, which evaluated a body condition score (BCS; 1 = thinnest, 5 = fattest) every other month and fecal glucocorticoid metabolite (FGM) concentrations twice monthly in 33 tourist camp elephants in Thailand for a 1-year period to assess seasonal variations, and determine how lipid profiles [total cholesterol (TC), low density lipoproteins (LDL), high density lipoproteins (HDL), triglycerides (TG)] and metabolic parameters [insulin, glucose, fructosamine, glucose to insulin ratio (G:I)] related to measures of body condition and adrenal function. The most prevalent BCS was 3–3.5 (60.6%), with 27.3% at BCS = 4 (overweight) and 12.1% at BCS = 4.5–5 (very overweight); no elephants had a BCS <2. BCSs were higher in rainy and winter seasons compared to summer, with FGM, TG, HDL, LDL, and insulin also higher in the rainy and/or winter seasons (p<0.05). By contrast, TC and glucose were lowest in the rainy season. FGM measures were negatively associated with two environmental factors: temperature and rainfall, but not humidity. Positive correlations were found between BCS and TC, LDL, and HDL, and between FGM and TC, HDL, glucose, and insulin (p<0.05), whereas BCS and FGM were both negatively associated with the G:I (p<0.05). However, there was no relationship between BCS and FGM among the camp elephants. Using BCS and FGM measures as outcome variables in separate regression models, this study found high BCS and elevated FGM concentrations were associated with altered lipid profiles and metabolic status in elephants. Furthermore, more work hours/day was associated with better body condition and health measures. Thus, being overweight and exposed to factors that increase adrenal activity could adversely affect health status, requiring alterations in management for some individuals, whereas exercise appears to have a protective effect.

show abstract

“…Hormone monitoring in particular can be used to assess physiological health, and is increasingly used to enhance reproduction and welfare of ex-situ and in-situ populations of various taxa [1]. Through longitudinal measures of hormones in elephants in western zoos, we have characterized basic endocrine function and determined how environmental factors (e.g., social structures, life events, climate, feeding strategy) affect gonadal and adrenal function [2,3]. We have used this information to improve captive management through better timing of breeding (both natural and assisted), providing more social opportunities, and improving exhibit design and husbandry to enhance elephant welfare.…”

Section: Introductionmentioning

confidence: 99%

Effects of physiological changes and social life events on adrenal glucocorticoid activity in female zoo-housed Asian elephants (Elephas maximus)

et al. 2020

Self Cite

View full text Add to dashboard Cite

Ensuring good health and welfare is an increasingly important consideration for conservation of endangered species and includes breeding of individuals managed under human care. Understanding how factors in the captive environment affect individual animal wellbeing can be aided by long-term monitoring of biological functioning. This study involved longitudinal assessments (4 to 28 years) of reproductive and adrenal hormones in zoo-housed female Asian elephants (Elephas maximus) (age range 4 to ~71 years) to elucidate patterns in adrenal glucocorticoid (GC) activity in association with reproductive and demographic factors, and examine individual response to major social changes. Concentrations of serum and urinary cortisol covaried more consistently with physiological changes (ovarian cycle phase, puberty, pregnancy, lactational anestrus, and age) than with social life events (births, deaths, and facility transfers). Cortisol fluctuated across the ovarian cycle with mean concentrations being higher in the follicular than in the luteal phase, and concentrations were highest in lactational anestrous compared to all other reproductive states. The elephants in this study exhibited substantial individuality in adrenal GC response to major social change, reinforcing the need to assess welfare on an individual basis and to consider factors influencing the impact of perceived stressors, such as social relationships, social support, temperament, and life history. Outcomes from this study deepen our understanding of Asian elephant physiology and highlight the importance of taking intrinsic patterns of hormone secretion into account when evaluating the impact of external factors. Finally, a better understanding of the impact of social change and resiliency in response to real and perceived stressors allows us to improve social management to enhance welfare in both captive settings and free-ranging environments.

show abstract

Comparative Reproductive Biology of Elephants

Cited by 32 publications

References 154 publications

Zoo elephant research: contributions to conservation of captive and free‐ranging species

Zoo elephant research: contributions to conservation of captive and free‐ranging species

Body condition and adrenal glucocorticoid activity affects metabolic marker and lipid profiles in captive female elephants in Thailand

Effects of physiological changes and social life events on adrenal glucocorticoid activity in female zoo-housed Asian elephants (Elephas maximus)

Contact Info

Product

Resources

About