Preorbital secretions

Burger, B.V., Tien, F.-C., LeRoux, M. and Mo, W.-P. (1996) Mammalian exocrine secretions X. Constituents of preorbital secretion of grysbok, Raphicerus melanotis. J.Chem.Ecol. 22, 739-764. 

Chemical work on the exocrine secretions of African antelope has concentrated on the interdigital secretions of members of the subfamily Alcelaphinae and the preorbital secretions of members of the subfamilies Antilopinae and Cephalo-phinae. 

Members of the subfamily Antilopinae, known as dwarf antelope, have well-developed preorbital glands. In both sexes the preorbital gland is a thin-walled pocket anterior to the forward corner of the eye, the secretions of which are used for territorial marking. It would be impossible to present and discuss in detail the enormous volume of chemical information on the preorbital secretions of these animals that has been accumulated over more than 30 years (e.g. [8, 17, 18, 136, 140-143]). The compounds identified in the preorbital secretion of the Cape grysbok, Raphicerus melanotis, are, however, listed in Table 8 [18] to exemplify the compounds that are typically found in these secretions, with one notable exception (see below). 

Table 8 Compounds identified in the preorbital secretion of the grysbok, Raphicerus melanotis [18]... 

The results of the chemical characterization of the preorbital secretions of these dwarf antelope are summarized in Table 9 [140]. Due to the large number of double-bond positional isomers in the secretions of some of the members of the tribe, it is impossible to include all the relevant information in the table. 

Table 9 Compound types3 identified in the preorbital secretions from antelope of the subfamily Antilopini [ 140]... 

Table 10 Compoundsidentified in the mucous and wax phases of the preorbital secretion of the redduiker, Cephalophus natalensis[22, A ]... 

The anal gland secretion of beaver, C. canadensis, differs between the sexes (Gr0nneberg, 1978-79). The male grey duiker, Sylvicapra grimmia, has more 2-heptanone and 2-nonadecanone in its preorbital secretion than the female. Two thiazoles (2-isobutyl-1,3-thiazole and 2-isobutyl-4,5-dihydro-l,3-thiazole) and an epoxy ketone (3,4-epoxy-2-dodecanone) are also more abundant in the male s secretion. Correlated with these chemical differences is the fact that only males scent mark with the preorbital gland (Burger etal., 1990). 

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