geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Chemical signals in the reproduction of Asian and African elephants


, : Chemical signals in the reproduction of Asian and African elephants. Animal Reproduction Science 53(1-4): 19-34, Oct

Asian (Elephas maximus) and African (Loxodonta africana) elephants exhibit polygynous mating that involves female choice of mates and male-male competition for access to females. Chemical signals mediate intersexual and intrasexual interactions associated with reproduction. The need for reliable and honest signals is accentuated by the markedly different social structure of adult males and females. Adult female elephants live in matriarchal herds consisting of a dominant female and several generations of offspring. Adult males are solitary or travel with other males except during breeding periods. Because females have a long 16-week oestrous cycle with a brief 1-week receptive period and a 4-5 year interval between births, a sexually active female is a limited resource. Asian elephant females advertise a forthcoming ovulation by releasing (Z)-7-dodecen-1-yl acetate in their urine during the preovulatory period. African elephants probably produce a sex pheromone as well. Females regularly contact the ano-genital region of other females and show heightened chemosensory responsiveness to urine during the follicular phase. The physiological impacts of this ability to detect reproductive condition (e.g. possible synchronizing or suppressing of oestrus) are uncertain. Males experience an annual period of heightened aggressiveness and highly elevated testosterone concentrations known as musth. Males secrete fluid copiously from their temporal gland and dribble strongly odoriferous urine during musth. Females appear to prefer musth males as mates, and captive Asian females exhibit greater chemosensory responses to urine from males in musth than not. Males in musth are competitively dominant to all other males, even those larger than themselves. Nonmusth males avoid males in musth, and captive Asian bulls show greater interest in musth than nonmusth urine. In captivity subordinate Asian females back away from musth secretions, and females with calves sometimes display protective behaviour. Clearly, chemical signals play an important role in communication by elephants between and within the sexes. Further work is needed to identify more of these chemical messengers and to understand their complete function in mediating reproductive interactions in the elephant social system.

US$29.90


Other references

Lombardi, M.C.C.; Nobrega, J.A.; Nogueira, A.R.A., 2002: Focused microwave-assisted procedure for micronutrient extraction from soil samples with DTPA solution. This study presents an alternative procedure for the extraction of micronutrients from soil samples for fertility evaluation. Samples from an interdisciplinary programme for soil analysis with different physical and chemical characteristics were s...

Williams, J.M.; Adewunmi, A.; Schek, R.M.; Flanagan, C.L.; Krebsbach, P.H.; Feinberg, S.E.; Hollister, S.J.; Das, S., 2005: Bone tissue engineering using polycaprolactone scaffolds fabricated via selective laser sintering. Polycaprolactone (PCL) is a bioresorbable polymer with potential applications for bone and cartilage repair. In this work, porous PCL scaffolds were computationally designed and then fabricated via selective laser sintering (SLS), a rapid prototyp...

Motisuki, C.; Monti Lima, L.; Emi Sanabe, M.; Jacques, P.; Santos-Pinto, L., 2007: Evaluation of the microtensile bond strength of composite resin restoration in dentin prepared with different sizes of aluminum oxide particles, using the air abrasion system. The purpose of this in vitro study was to evaluate the influence of the abrasive technique on the microtensile bond strength of composite resin restorations. In addition, any differences in the microtensile bond strength were observed when differe...

Goyert, K., 1942: Experimental investigations on the iodine content of the skin of humans and animals under normal conditions and in inflammation. The method used was a modification of Leipert's technique. Normal skin contains considerably more I than blood: 150-200 [gamma] % (post mortem investigations of skin taken from the trunk). In the rabbit, the blood-I has the same concn. as in...

Tedgui, A.; Mallat, Z., 2003: Balance inflammatoire et atherosclerose. Atherosclerosis is a vascular pathology in which inflammation plays a major role at every stage of the disease. The inflammatory process develops in response to abnormal cholesterol deposits in the intima of large arteries. The inflammatory reacti...

Lyashenko, N.I.; Kulinich, M.A., 1986: Chemical systematics of hop in relation to the composition of the essential oils and bitter substances. The composition of essential oils was shown to be specific to a variety and did not change with growing conditions. The hydrocarbon composition of these oils was considered a useful criterion for varietal identification. Resin production and the q...

Porter, H.J.; Heryet, A.; Quantrill, A.M.; Fleming, K.A., 1990: Combined non-isotopic in situ hybridisation and immunohistochemistry on routine paraffin wax embedded tissue: identification of cell type infected by human parvovirus and demonstration of cytomegalovirus DNA and antigen in renal infection. A method for combined immunohistochemistry using alkaline phosphatase antialkaline phosphatase (APAAP) and in situ hybridisation using biotinylated probes was developed. The method requires no change to either technique and no additional procedure...

Matsubara, N.; Uemura, H.; Fukui, I.; Niwakawa, M.; Yamaguchi, A.; Iizuka, K.; Akaza, H., 2014: Phase-1 study of abiraterone acetate in chemotherapy-naïve Japanese patients with castration-resistant prostate cancer. Persistent androgen synthesis under castration status in adrenal gland, testes and tumor cells is thought to be one of the major causes of development and progression of castration-resistant prostate cancer (CRPC). Abiraterone acetate (AA), the pr...

Chaube, S.; Kronick, S.A.; Katz, A.D.; Karnofsky, D.A., 1961: Behavior of transplantable rodent and human tumors when introduced by various routes into the fertile chick egg. Proc Amer Assoc Cancer Res 3(3): 215

Maskina, M.S.; Power, J.F.; Doran, J.W.; Wilhelm, W.W., 1993: Residual effects of no-till crop residues on corn yield and nitrogen uptake. The residual effects of crop residues on N availability and crop growth are largely unknown. A field experiment was conducted from 1986 through 1988 at Lincoln, NE, to determine the residual effects on no-till corn (Zea mays L.) production and N u...