Gas-Chromatographic Analyses of the Subcaudal Gland Secretion of the European Badger (Meles meles) Part I: Chemical Differences Related to Individual Parameters

In many species, chemical signals are important in the context of intraspecific communication. European badgers (Meles meles) use the secretion of their subcaudal gland to mark both the environment and conspecifics. In this paper, we investigated the chemical composition of subcaudal gland secretions and how it varies among individuals according to group membership, season, sex, age, body condition, and reproductive status. We analyzed 66 samples by gas chromatography using a mass-spectrometer as detector. We found 110 different components, of which 21 were present in every profile. The chemical composition of the secretions proved to be highly individual-specific, but no single peak was found to be typical for one of the investigated categories (season, sex, etc.). Analyses of the relative area (% area) that every peak contributed to the overall profile area showed that, in general, group members have more similar profiles than do badgers from different groups. Composition varied over seasons and between sexes and was influenced by age, body condition, and reproductive status. We, therefore, conclude that the secretion not only encodes group membership and individuality as previously assumed, but might also convey information about fitness-related parameters.     

Volatile Compounds from Anal Glands of the Wolverine, <Emphasis Type="Italic">Gulo gulo</Emphasis>

Dichloromethane extracts of wolverine (Gulo gulo, Mustelinae, Mustelidae) anal gland secretion were examined by gas chromatography–mass spectrometry. The secretion composition was complex and variable for the six samples examined: 123 compounds were detected in total, with the number per animal ranging from 45 to 71 compounds. Only six compounds were common to all extracts: 3-methylbutanoic acid, 2-methylbutanoic acid, phenylacetic acid, α-tocopherol, cholesterol, and a compound tentatively identified as 2-methyldecanoic acid. The highly odoriferous thietanes and dithiolanes found in anal gland secretions of some members of the Mustelinae [ferrets, mink, stoats, and weasels (Mustela spp.) and zorillas (Ictonyx spp.)] were not observed. The composition of the wolverine’s anal gland secretion is similar to that of two other members of the Mustelinae, the pine and beech marten (Martes spp.).     

Volatile components in defensive spray of the hog-nosed skunk,Conepatus mesoleucus

GC-MS analysis of the anal sac secretion from the hog-nosed skunk,Conepatus mesoleucus, showed two major volatile components, (E)-2-butene-1-thiol and (E)-S-2-butenyl thioacetate. Minor volatile components identified from this secretion were phenylmethanethiol, 2-methylquinoline, 2-quinolinemethanethiol, and bis[(E)-2-butenyl] disulfide. 3-Methyl-1-butanethiol, a major component in the defensive spray of the striped skunk,Mephitis mephitis, and the spotted skunk,Spilogale putorius, was absent from this secretion.     

Volatile components in defensive spray of the spotted skunk,Spilogale putorius

GC-MS analysis of the anal sac secretion from the spotted skunk,Spilogale putorius, showed three major volatile components: (E)-2-butene-1-thiol, 3-methyl-1-butanethiol, and 2-phenylethanethiol. Minor volatile components identified from this secretion were: phenylmethanethiol, 2-methylquinoline, 2-quinolinemethanethiol, bis[(E)-2-butenyl] disulfide, (E)-2-butenyl 3-methylbufyl disulfide, bis(3-methylbutyl) disulfide. All of these compounds except 2-phenylethanethioi have been identified previously from the striped skunk,Mephitis mephitis. The thioacetate derivativesS- (E)-2-butenyl thioacetate,S-3-methylbutanyl thioacetate, andS-2-quinolinemethyl thioacetate found in the striped skunk were not seen in this species.     

Gas-Chromatographic Analyses of the Subcaudal Gland Secretion of the European Badger (Meles meles) Part II: Time-Related Variation in the Individual-Specific Composition

Individuality in body odors has been described in a variety of species, but studies on time-related variation in individual scent are scarce. Here, we use GC-MS to investigate how chemical composition of subcaudal gland secretions of European badgers (Meles meles) varies over days, seasons, and from year to year, and how secretions change with the length of time for which they are exposed to the environment. Samples were divided into subsamples—one was frozen immediately and the remaining ones frozen after 2, 6, 12, 24, and 48 hr, respectively—and many individual-specific characteristics of the scent-profiles remained stable over time. However, two components were negatively correlated with time, thus providing the possibility to determine the age of scent marks. The low variation found in scent profiles of samples collected from the same individual three days apart showed that the individual-specific scent is a true characteristic of the respective badger, and that trapping and subsequent sampling have little effect on the composition of subcaudal gland secretions. Long-term variation (i.e., over one year) in individual subcaudal scent profiles is not continuous, but periods of relative stability are followed by periods of rapid change, that can be related to badger biology. Annual variation between samples collected from the same individuals in winter 1998 and winter 1999, and in spring 1998 and spring 1999 was lower than seasonal variation. Therefore, the results of this study indicate the potential of an individual-specific scent signature in the subcaudal gland secretions of badgers evidencing that individual recognition is of high importance in this species.