Temporal gland secretions Asian elephant

Frontalin in the temporal gland secretion of Asian elephants is bound to elephant albumin (Schulte etal, 2005). The bulk of the secretion of the chin gland of the rabbit is protein (Goodrich and Mykytowycz, 1972). 

The Asian elephant has farnesol, 4-ethylphenol and 4-methylphenol in its temporal gland secretion while the African elephant has only 4-methylphenol. Farnesol levels are inversely related to testosterone levels (Rasmussen and Perrin, 1999). Preovulatory female urine contains (Z)-7-dodecen-l-yl acetate (Rasmussen etal, 1996). 

Even adults can still develop olfactory preferences that contravene those acquired before sexual maturity. Female laboratory mice imprinted by the odor of one mouse strain will prefer this odor even more if they are exposed to males of this strain as adults. However, if they are exposed to males of a different strain when sexually mature, their original odor preference will be reversed (Albonetti and D Udine, 1986). Naturally occurring sex or body odors may assume their sexual significance after association with sexual activity male mice were aroused by a perfume that they had experienced earlier on scented females they had interacted with (Nyby etal., 1978). Practitioners have known that adult mammals can acquire responses after exposure to certain animals. For instance, bulls of the Asian elephant that had been housed near African elephant bulls respond to temporal gland secretion and its three components phenol, 4-methylphenol, and (E)-farnesol from the latter species. Asian bulls thathad not been associated with African bulls did not respond (Rasmussen, 1988). 

Rasmussen, L. E. L., Hess, D. L., and Haight, J. D., 1990, Chemical analysis of temporal gland secretions collected from an Asian bull elephant during a four-month musth episode, J. Chem. Ecol. 16(7) 2I67-2181. 

Rasmussen, L. E. L., Perrin, T. E., and Ounawardena, R., 1994, Isolation of potential musth-alerting signals from temporal gland secretions of male Asian elephants (Elephas maximus), a new method, Chem. Senses 19(5) 540. 

TEMPORAL GLAND SECRETION SIGNALS DURING MUSTH IN MALE ASIAN ELEPHANTS... 

Table II. Temporal properties and chemical identities of potential chemical signals from temporal gland secretions of Asian male elephants in musth...

Easa, PS. 1987. Chemical composition of the temporal gland secretion of an Asian elephant Elephas maximus). Elephant, 2, 67—68. 

Figure 1. Deviant behavior (O) and serum testosterone concentration ( ) of a captive Asian bull elephant (Packy, 32 years old) throughout a musth episode (premusth through postmusth). Deviant behavior was the weekly mean of five individual behaviors each graded on a 0-4 scale daily. Serum testosterone (ng/ml) was measured weekly. Solid arrows indicate start and end of temporal gland secretion (TGS), which was delineated as the musth period. The dashed arrow indicates the beginning of urine dribbling (cessation was simultaneous with end of TGS).

Figure 4. Testosterone concentration (ng/ml) in temporal gland secretion and relative abundance of four groups (I-IV) of compounds present in TGS over the course of musth in Tunga, an Asian bull elephant (a different elephant from the previous figures). Group I cyclohexanone, benzoic acid, phenylacetic acid, phenylpropanoic acid, octanoic acid, 3-octen-2-one and4-n-nonylphenol. Group II 5-nonanol, 2-hydroxyacetophenone, 1,3 dihydro-2H-indol-2-one, 2-nonanone, unidentified and 3-nonen-2-one. Group III phenol, decanoic acid and famesol. Group IV 4-hexenoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid and dotriacontanol.

Fig, 5. Chemical communication mediated via the flehmen response in Asian elephants. Urine and temporal gland secretions both elicit flehmen responses. Emphasis of the diagram is on sex state information. 

First identified in Asian elephants during a headspace analysis of volatiles collected from secretions of the musth temporal gland of adult males,156 frontalin (52) is a bicyclic ketal, which is structurally reminiscent of the male mouse priming pheromone component 3,4-dehydro-ara-brevicomin (37). Frontalin (52), Z-7-dodecen-l-yl acetate (51), was already known because of its chemosensory role in the insect world it is an aggregation pheromone in bark beetles.157 Interestingly, the ratio of the two enantiomers of frontalin (52) changes with age and stage of musth and elicits different behavioral responses.158... 

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