Abstracts - Association for Chemoreception Sciences

P O S T E R S
#P122 POSTER SESSION III: OLFACTORY
PERCEPTION, HUMAN PSYCHOPHYSICS &
ANIMAL BEHAVIOR; PERIPHERAL TASTE
DEVELOPMENT & SIGNALING
Newly Discovered Specific Anosmias
Charles J. Wysocki 1 , Jennifer Louie 1 , Lisa Oriolo 1 , Angelica Au 1 ,
Edward Strojan 1 , Makoto Emura 2 , Michael Lankin 3
1
Monell Chemical Senses Center Philadelphia, PA, USA,
2
TAKASAGO International Corporation Hiratsuka-shi,
Kanagawa, Japan, 3 TAKASAGO International Corporation
Rockleigh, NJ, USA
Specific anosmia is an inability to perceive an odor when others
can readily detect such although the general sense of smell is
intact. To date, specific anosmias for only a handful of odorants
have been described. We explored human responses to 10
compounds. Herein, we note that some human subjects could not
smell some of the odorants, viz., 3-hydroxy-3-methylhexenoic
acid, 2-nonenal, skatole and geosmin, malodorants commonly
encountered by people. We determined olfactory detection
thresholds for these compounds by using triangle tests (2 blanks
versus the target) beginning at the lowest concentration of each
(n of human subjects = 99, 177, 174 and 134, respectively). The
highest concentrations were 0.1%, 0.01%, 0.01% and 0.067% and
9 subsequent dilutions were 3-, 5-, 3- and 3-fold, respectively. For
each triangle test the subject had to choose the odorant-containing
plastic squeeze bottle (270 ml capacity containing 10 ml of diluted
odorant or diluent [mineral oil]) and provide a confidence rating
for the choice (3=certain; 2=possible; 1=guess). Each series was
subjected to an ascending method of limits, which terminated
when four correct steps were satisfied with a confidence rating
summed across the last four trials of at least 7). We defined
specific anosmia as reaching the highest concentration without
meeting the criteria or at least 3 standard deviations above the
mean. The percentage of people with specific anosmias was
14.1%, 6.2%, 2.3% and 6.0% respectively. These data suggest that
there may be far more specific anosmias than previously reported:
In the 10 selected for in-depth study, 40% could not be detected
by a subset of those tested. Perhaps these result from altered or
absent gene expression. Acknowledgements: Supported by NIH
RO1 DC00298 to CJW and support from TAKASAGO.
#P123 POSTER SESSION III: OLFACTORY
PERCEPTION, HUMAN PSYCHOPHYSICS &
ANIMAL BEHAVIOR; PERIPHERAL TASTE
DEVELOPMENT & SIGNALING
Early Odor Learning in Tree Swallows (Tachycineta bicolor)
Meredyth P. Duncan, Ashley A. Miniet, Julie C. Hagelin
Department of Biology, Swarthmore College Swarthmore, PA,
USA
Perching birds (Passerines) have exceedingly small olfactory bulbs
and their chemosensory abilities are only minimally studied. We
investigated the Tree Swallow (Tachycineta bicolor), a common
migratory passerine that breeds in North America. We tested:
(1) whether swallow chicks could detect odors, and (2) whether
exposure to an experimental odor early in life would alter a
chick’s response. Our field-study involved chicks from two nest
types. In experimental nests (n = 15) all chicks were exposed to
the scent of peppermint oil during incubation and chick rearing,
whereas those in control nests (n = 31) were not. At nine days of
age we tested chicks for their reaction to peppermint oil, fox urine
(a putative predator scent), and an odorless control using the
Porter method (Porter et al. 1999). Chicks from both treatments
detected test odors relative to the odorless control (2.28 ≤ t ≤ 3.39,
0.004 ≤ P ≤ 0.031). Next, we compared the degree with which
birds from each treatment discriminated between our two test
scents by subtracting a chick’s response to mint from its response
to fox. Chicks reared in mint odor exhibited values that were
nearly twice that of controls (t = 2.05, df = 44, P = 0.046),
suggesting that early exposure to mint altered a bird’s ability to
differentiate between mint and fox odors. Birds in experimental
boxes appeared more familiar with mint in that they reacted less
strongly to mint than to the unfamiliar odor of fox. By contrast,
birds from control boxes reacted similarly to mint and fox, both
of which were unfamiliar odors. Our results suggest that
chemosensory learning can occur early on in passerine
development and we suspect this may be true of other birds.
Studies of odor imprinting are a promising future step for avian
research. Acknowledgements: An HHMI Undergraduate Summer
Research stipend was granted to AAM. MPD was supported by a
summer research grant from the Natural Sciences Division of
Swarthmore College.
#P124 POSTER SESSION III: OLFACTORY
PERCEPTION, HUMAN PSYCHOPHYSICS &
ANIMAL BEHAVIOR; PERIPHERAL TASTE
DEVELOPMENT & SIGNALING
Exploring the Olfactory Ability of the Kea (Nestor notabilis),
an Endangered Parrot from New Zealand
Kimberly F. Kramer 1 , Regina L. Kukola 2 , Christine Q. Ernst 1 ,
Julie C. Hagelin 1
1
Department of Biology, Swarthmore College Swarthmore, PA,
USA, 2 Department of Biology, Bryn Mawr College Bryn Mawr,
PA, USA
The Kakapo (Strigops habroptilis) is a critically endangered,
endemic parrot of New Zealand known for its nocturnal habit and
olfactory ability (Hagelin 2004). Most parrots, however, are
diurnal and their chemosensory abilities are practically unstudied.
The Kea (Nestor notabilis) offers a particularly interesting
comparison, because this endangered species is a diurnal relative
of the Kakapo. We studied two captive Keas at the Philadelphia
Zoo to determine whether birds could detect amyl acetate (banana
odor). As part of an enrichment regimen birds were given either
toy balls of perforated plastic that had been internally treated with
scent or identical balls that were unscented. Pilot testing led us to
focus on an unusual behavior, “face rubbing,” in which a bird
wipes its cheeks, nostrils or beak against the outside of balls. Over
60-minute trials the behavior of each bird was scored by an
observer blind to the toy treatment. Face-rubbing was more likely
to occur when birds played with scented balls (N = 21 trials,
Fisher’s exact P = 0.03). Our result indicates that Keas can detect
and react differently to toys treated with banana odor. Scented
toys are a practical means of providing base-line information
about the chemosenses for many avian species. We also suggest
that this method may be a potentially useful but overlooked
means of enrichment for captive birds.
68 | AChemS Abstracts 2010 Abstracts are printed as submitted by the author(s)