Attractive Odor Research Articles

Alterations in the odor profile of plants in cultivar mixtures affect aphid host-location behavior.

The effect of cultivar mixtures on aphid control is attributed to the masking or alteration of host-preferred cultivar odor cues. However, the underlying physiological mechanism remains unclear. This study assessed alterations in the volatile emissions of wheat cultivars grown together (Florence-Aurora and Forment; Florence-Aurora and Montcada) and the consequences for the olfactory preference of aphids. Volatile organic compounds were collected from wheat plants grown in a laboratory under mixed or monoculture conditions and subsequently analyzed. The odor profiles of Florence-Aurora and Montcada were indistinguishable from each other. However, the odors of Florence-Aurora and Forment grown in monocultures differed significantly from those emitted by their mixture. The Florence-Aurora and Forment mixture induced plant physiological responses that affected the emission of single volatile compounds and, consequently, altered volatile organic compound ratios. English grain aphids (Sitobion avenae) were less attracted to the odors of Florence-Aurora and Forment when grown as a mixture than the combination of the odors from Florence-Aurora and Forment monocultures. Moreover, aphids preferred clean air over the odor from the Florence-Aurora and Forment mixture but preferred the odor from the Florence-Aurora and Montcada mixture over clean air. This study highlights the beneficial effects of intraspecific plant diversity on aphid control by altering plant odors in response to plant-plant interactions. The emission of less attractive odor cues consequently affects plant-aphid interactions; hence, less attractive odors are likely to impair aphid host-locating behavior. This effect was exclusive to certain cultivar mixtures, which supports the "right neighbor" concept.

A test of multimodal communication in humans using 881 judgements of men and women's physical, vocal, and olfactory attractiveness

Human mate value is assessed on numerous variables including, reproductive potential and disease resistance. Many of these variables have been correlated with judgments of physical, vocal, and odor attractiveness. While some researchers posit that attractiveness judgments made across different sensory modalities reflect the same underlying variable(s) (i.e., the information is redundant), others suggest that judgments made in different modalities reflect different variables. Previous studies of human attractiveness indicate that attractiveness judgments of others’ faces, bodies, and voices are intercorrelated, which is suggested to support the redundancy hypothesis. Less is known about body odor attractiveness. Only one study has simultaneously investigated the relationships between judgments of body odor, face, and voice attractiveness finding weak positive associations, but small effect sizes. In this study, we empirically investigate the correlation between different modalities of attractiveness in men and women in the largest sample to date (N = 881 ratings). For men, we find no correlations between modalities of attractiveness. However, for women we find odor, face, and voice attractiveness are weakly correlated. Moreover, a general attractiveness factor (i.e., a common underlying variable) modestly contributed to the observed correlations between modality-specific attractiveness judgments, providing some evidence for the redundancy hypothesis.

Infection of Trichinella spiralis Affects the Reproductive Capacity of ICR/CD-1 Male Mice by Reducing the Urine Pheromone Contents and Sperm Quality.

Female mice can discriminate the urinary odors of male mice due to their olfactory acuity. Parasitic infection or subclinical infection can decrease the odor attractiveness of male mice and finally lead to aversion or avoidance responses in odor selection for female mice. Trichinella spiralis is a kind of tissue-parasitizing nematode that causes trichinellosis, a zoonotic parasitic disease that spreads throughout the world. However, the reproductive injury caused by Trichinella spiralis infection was not fully revealed. In this study, we explored the effect of Trichinella spiralis infection on the reproductive capacity in ICR/CD-1 male mice. We identified eight volatile compounds in urine by GC-MS analysis, and the results indicated that the contents of dimethyl sulfone, Z-7-tetradecen-1-ol, 6-Hydroxy-6-methyl-3-heptanone and (S)-2-sec-butyl-4,5-dihydrothiazole were significantly downregulated after parasitic infection, which might lead to the reduction of attractiveness of male mice urine to females. On the other hand, parasitic infection decreased sperm quality and downregulated the expression levels of Herc4, Ipo11, and Mrto4, and these genes were strongly related to spermatogenesis. In summary, this study revealed that the reproductive injury caused by Trichinella spiralis infection in ICR/CD-1 male mice could be associated with a decrease in urine pheromone content and sperm quality.

Infection with Cryptosporidium parvum Affects Secondary Sexual Characteristics of Male Mice by Altering the Pheromone Content in Preputial Gland

The olfactory acuity of female mice allows them to discriminate the urinary odors of males. Parasitic infection can reduce the odor attractiveness of male mice to females and result in female aversion or avoidance responses in odor selection. However, the chemical signaling changes in the pheromone contents produced by the foreskin gland were not fully revealed after parasitic infection. Cryptosporidium parvum (C. parvum) is a common zoonotic intestinal parasite and has a wide range of hosts, including human, domestic animals, and wild animals. In this study, we immunosuppressed ICR/CD-1 male mice by dexamethasone sodium phosphate treatment. After C. parvum infection, physiological indexes such as body weight and organ weight were significantly decreased. Furthermore, the gene expression level of MUP (major urinary protein) in liver and urine were significantly down-regulated, which could be the reason for the decrease in urine attractiveness to females. GC-MS was performed to analyze the changes in the pheromone produced by the preputial gland before and after parasitic infection, and the results indicated that the levels of different pheromones were significantly reduced after parasitic infection. In summary, this study reveals that C. parvum infection damages the secondary sexual characteristics of male ICR/CD-1 male mice and decreases the pheromone content produced by the foreskin gland.

Active antennal movements in Drosophila can tune wind encoding

Insects use their antennae to smell odors,1,2 detect auditory cues,3,4 and sense mechanosensory stimuli such as wind5 and objects,6,7,8 frequently by combining sensory processing with active movements. Genetic access to antennal motor systems would therefore provide a powerful tool for dissecting the circuit mechanisms underlying active sensing, but little is known about how the most genetically tractable insect, Drosophila melanogaster, moves its antennae. Here, we use deep learning to measure how tethered Drosophila move their antennae in the presence of sensory stimuli and identify genetic reagents for controlling antennal movement. We find that flies perform both slow adaptive movements and fast flicking movements in response to wind-induced deflections, but not the attractive odor apple cider vinegar. Next, we describe four muscles in the first antennal segment that control antennal movements and identify genetic driver lines that provide access to two groups of antennal motor neurons and an antennal muscle. Through optogenetic inactivation, we provide evidence that antennal motor neurons contribute to active movements with different time courses. Finally, we show that activation of antennal motor neurons and muscles can adjust the gain and acuity of wind direction encoding by antennal displacement. Together, our experiments provide insight into the neural control of antennal movement and suggest that active antennal positioning in Drosophila may tune the precision of wind encoding.

A comparison of odor plume-tracking behavior of walking and flying insects in different turbulent environments.

Many animals locate food, mates and territories by following plumes of attractive odors. There are clear differences in the structure of this plume-tracking behavior depending on whether an animal is flying, swimming, walking or crawling. These differences could arise from different control rules used by the central nervous system during these different modes of locomotion or one set of rules interacting with the different environments while walking on the surface versus flying or swimming. Flow speeds and turbulence that characterize the environments where walking and flying insects track plumes may alter the structure of odor plumes in an environment-specific way that results in the same control rules generating behaviors that appear quite different. We tested these ideas by challenging walking male cockroaches, Periplaneta americana, and flying male moths, Manduca sexta, to track plumes of their species' sex pheromones in low wind speeds characteristic of cockroach experimental environments, higher wind speeds characteristic of moth experimental environments, and conditions ranging from low to high turbulence. Introducing a turbulence-generating structure into the flow significantly improved the flying plume tracker's ability to locate the odor source, and changed the structure of the behavior of both flying and walking plume trackers. Our results support the idea that plume trackers moving slowly along the substrate may use the spatial distribution of odor, while faster moving flying plume trackers may use the timing of odor encounters to steer to locate the source.

Cross-modal associations of human body odour attractiveness with facial and vocal attractiveness provide little support for the backup signals hypothesis: A systematic review and meta-analysis

Cross-modal associations of human body odour attractiveness with facial and vocal attractiveness provide little support for the backup signals hypothesis: A systematic review and meta-analysis

Machine learning-based clustering and classification of mouse behaviors via respiratory patterns.

Breathing is dynamically modulated by metabolic needs as well as by emotional states. Even though rodents are invaluable models for investigating the neural control of respiration, current literature lacks systematic characterization of breathing dynamics across a broad spectrum of rodent behaviors. Here we uncover a wide diversity in breathing patterns across spontaneous, attractive odor-, stress-, and fear-induced behaviors in mice. Direct recordings of intranasal pressure afford more detailed respiratory information than more traditional whole-body plethysmography. K-means clustering groups 11 well-defined behavioral states into four clusters with distinct key respiratory features. Furthermore, we implement RUSBoost (random undersampling boost) classification, a supervised machine learning model, and find that breathing patterns can separate these behaviors with an accuracy of 80%. Taken together, our findings highlight the tight relationship between breathing and behavior and the potential use of breathing patterns to aid in distinguishing similar behaviors and inform about their internal states.

Glial regulators of ions and solutes required for specific chemosensory functions in Caenorhabditis elegans.

Glia and accessory cells regulate the microenvironment around neurons and primary sensory cells. However, the impact of specific glial regulators of ions and solutes on functionally diverse primary cells is poorly understood. Here, we systemically investigate the requirement of ion channels and transporters enriched in Caenorhabditis elegans Amsh glia for the function of chemosensory neurons. Although Amsh glia ablated worms show reduced function of ASH, AWC, AWA, and ASE neurons, we show that the loss of glial enriched ion channels and transporters impacts these neurons differently, with nociceptor ASH being the most affected. Furthermore, our analysis underscores the importance of K+, Cl-, and nucleoside homeostasis in the Amphid sensory organ and uncovers the contribution of glial genes implicated in neurological disorders. Our findings build a unique fingerprint of each glial enriched ion channel and transporter and may provide insights into the function of supporting cells of mammalian sensory organs.

Insulin/IGF signaling regulates presynaptic glutamate release in aversive olfactory learning.

Insulin/insulin-like growth factor (IGF) receptor signaling (IIS) supports context-dependent learning in vertebrates and invertebrates. Here, we identify cell-specific mechanisms of IIS that integrate sensory information with food context to drive synaptic plasticity and learning. In the nematode Caenorhabditis elegans, pairing food deprivation with an odor such as butanone suppresses attraction to that odor. We find that aversive olfactory learning requires the insulin receptor substrate (IRS) protein IST-1 and atypical signaling through the insulin/IGF-1 receptor DAF-2. Cell-specific knockout and rescue demonstrate that DAF-2 acts in the AWCON sensory neuron, which detects butanone, and that learning preferentially depends upon the axonally localized DAF-2c isoform. Acute food deprivation increases DAF-2 levels in AWCON post-transcriptionally through an insulin- and insulin receptor substrate-1 (ist-1)-dependent process. Aversive learning alters the synaptic output of AWCON by suppressing odor-regulated glutamate release in wild-type animals, but not in ist-1 mutants, suggesting that axonal insulin signaling regulates synaptic transmission to support aversive memory.

Internal state affects local neuron function in an early sensory processing center to shape olfactory behavior in Drosophila larvae

Crawling insects, when starved, tend to have fewer head wavings and travel in straighter tracks in search of food. We used the Drosophila melanogaster larva to investigate whether this flexibility in the insect’s navigation strategy arises during early olfactory processing and, if so, how. We demonstrate a critical role for Keystone-LN, an inhibitory local neuron in the antennal lobe, in implementing head-sweep behavior. Keystone-LN responds to odor stimuli, and its inhibitory output is required for a larva to successfully navigate attractive and aversive odor gradients. We show that insulin signaling in Keystone-LN likely mediates the starvation-dependent changes in head-sweep magnitude, shaping the larva’s odor-guided movement. Our findings demonstrate how flexibility in an insect’s navigation strategy can arise from context-dependent modulation of inhibitory neurons in an early sensory processing center. They raise new questions about modulating a circuit’s inhibitory output to implement changes in a goal-directed movement.

A dopamine-gated learning circuit underpins reproductive state-dependent odor preference in Drosophila females.

Motherhood induces a drastic, sometimes long-lasting, change in internal state and behavior in many female animals. How a change in reproductive state or the discrete event of mating modulates specific female behaviors is still incompletely understood. Using calcium imaging of the whole brain of Drosophila females, we find that mating does not induce a global change in brain activity. Instead, mating modulates the pheromone response of dopaminergic neurons innervating the fly's learning and memory center, the mushroom body (MB). Using the mating-induced increased attraction to the odor of important nutrients, polyamines, we show that disruption of the female fly's ability to smell, for instance the pheromone cVA, during mating leads to a reduction in polyamine preference for days later indicating that the odor environment at mating lastingly influences female perception and choice behavior. Moreover, dopaminergic neurons including innervation of the β'1 compartment are sufficient to induce the lasting behavioral increase in polyamine preference. We further show that MB output neurons (MBON) of the β'1 compartment are activated by pheromone odor and their activity during mating bidirectionally modulates preference behavior in mated and virgin females. Their activity is not required, however, for the expression of polyamine attraction. Instead, inhibition of another type of MBON innervating the β'2 compartment enables expression of high odor attraction. In addition, the response of a lateral horn (LH) neuron, AD1b2, which output is required for the expression of polyamine attraction, shows a modulated polyamine response after mating. Taken together, our data in the fly suggests that mating-related sensory experience regulates female odor perception and expression of choice behavior through a dopamine-gated learning circuit.

Ophiostomatoid fungi synergize attraction of the Eurasian spruce bark beetle, Ips typographus to its aggregation pheromone in field traps.

Eurasian spruce bark beetle, Ips typographus is a destructive pest of the Norway spruce (Picea abies). Recent outbreaks in Europe have been attributed to global warming and other anthropogenic impacts. Bark beetles are guided by multiple complex olfactory cues throughout their life cycle. Male-produced aggregation pheromones, comprising 2-methyl-3-buten-2-ol and cis-verbenol, have been identified as the most powerful attractants for dispersing conspecifics. In addition to host trees, bark beetles interact with multiple organisms, including symbiotic ophiostomatoid fungi, which may promote beetle colonization success and offspring development. Previously, in a short-distance laboratory assay, we demonstrated that I. typographus adults are attracted to the volatile organic compounds (VOCs) produced by three symbiotic fungi: Grosmannia penicillata, Endoconidiophora polonica, and Leptographium europhioides. Furthermore, the abundant fusel alcohols and their acetates were found to be the most attractive odorants in the fungal VOC profile. In this study, using a long-distance field-trapping experiment, we analyzed the role of fungal VOCs as attractants for dispersing I. typographus. Two types of fungal lures were tested in combination with pheromones in traps: (1) live cultures of fungi grown on potato dextrose agar (PDA) and (2) dispensers containing synthetic fusel alcohols and their acetates in equal proportions. Subsequently, the composition of VOCs emitted from live fungal lures were analyzed. We found that the symbiotic fungi synergistically increased the attraction of beetles to pheromones in field traps and the attractiveness of live fungal lures depended on the fungal load. While one Petri dish with E. polonica, when combined with pheromones synergistically increased trapping efficiency, three Petri dishes with L. europhioides were required to achieve the same. The synthetic mix of fungal fusel alcohols and acetates improved the catch efficiency of pheromones only at a low tested dose. VOC analysis of fungal cultures revealed that all the three fungi produced fusel alcohols and acetates but in variable composition and amounts. Collectively, the results of this study show that, in addition to pheromones, bark beetles might also use volatile cues from their symbiotic fungi to improve tree colonization and reproductive success in their breeding and feeding sites.

Regulation of Diacylglycerol Content in Olfactory Neurons Determines Forgetting or Retrieval of Olfactory Memory in Caenorhabditis elegans.

Proper management of memories by forgetting and retrieval is essential for animals to adapt their behavior to changing environments. To elucidate the mechanisms underlying forgetting, we use olfactory learning to an attractive odorant, diacetyl, in Caenorhabditis elegans hermaphrodites as a model. In this learning paradigm, the TIR-1/JNK-1 pathway in AWC sensory neurons accelerates forgetting of the olfactory memory, which is stored as a sensory memory trace in AWA sensory neurons. Our genetic screening revealed that increased neuronal diacylglycerol in the olfactory neuronal circuit, by mutations in diacylglycerol kinase-1, egl-30 or goa-1, Gq and Go type G-proteins, suppresses the forgetting defect in the behavior of tir-1 mutants, although the calcium imaging analyses of the olfactory neurons revealed that the sensory memory trace to the odorant was maintained. In contrast, the expression of a gain-of-function goa-1 gene exclusively in AWC neurons caused a forgetting defect in behavior, although their sensory memory trace declined. Furthermore, the behavioral analysis of animals applied with diacylglycerol analog and measurement of diacylglycerol content by fluorescent imaging suggested that diacylglycerol content in AWC is important for the proper forgetting. These findings raise a possibility that diacylglycerol signaling plays a crucial role in determining whether to forget or to recall in olfactory learning.SIGNIFICANCE STATEMENT Forgetting and retrieval are important processes for proper management of memories, although the mechanisms underlying these processes remain largely unclear. We found that, in Caenorhabditis elegans, diacylglycerol signaling works in a forgetting mechanism downstream of TIR-1/JNK-1 pathway. Mutations that change diacylglycerol content in the olfactory neurons affect behavioral forgetting, although they did not alter the sensory memory trace. This suggests that diacylglycerol in specific neurons may determine the occurrence of retrieving, rather than modifying, the memory traces. Consistent with this hypothesis, application of diacylglycerol analog to animals suggests that diacylglycerol content until memory acquisition decides whether to retrieve or to forget the memory.

Developmental history modulates adult olfactory behavioral preferences via regulation of chemoreceptor expression in Caenorhabditiselegans.

Developmental experiences play critical roles in shaping adult physiology and behavior. We and others previously showed that adult Caenorhabditiselegans which transiently experienced dauer arrest during development (postdauer) exhibit distinct gene expression profiles as compared to control adults which bypassed the dauer stage. In particular, the expression patterns of subsets of chemoreceptor genes are markedly altered in postdauer adults. Whether altered chemoreceptor levels drive behavioral plasticity in postdauer adults is unknown. Here, we show that postdauer adults exhibit enhanced attraction to a panel of food-related attractive volatile odorants including the bacterially produced chemical diacetyl. Diacetyl-evoked responses in the AWA olfactory neuron pair are increased in both dauer larvae and postdauer adults, and we find that these increased responses are correlated with upregulation of the diacetyl receptor ODR-10 in AWA likely via both transcriptional and posttranscriptional mechanisms. We show that transcriptional upregulation of odr-10 expression in dauer larvae is in part mediated by the DAF-16 FOXO transcription factor. Via transcriptional profiling of sorted populations of AWA neurons from control and postdauer animals, we further show that the expression of a subset of additional chemoreceptor genes in AWA is regulated similarly to odr-10 in postdauer animals. Our results suggest that developmental experiences may be encoded at the level of olfactory receptor regulation, and provide a simple mechanism by which C. elegans is able to precisely modulate its behavioral preferences as a function of its current and past experiences.

A neural circuit for wind-guided olfactory navigation

To navigate towards a food source, animals frequently combine odor cues about source identity with wind direction cues about source location. Where and how these two cues are integrated to support navigation is unclear. Here we describe a pathway to the Drosophila fan-shaped body that encodes attractive odor and promotes upwind navigation. We show that neurons throughout this pathway encode odor, but not wind direction. Using connectomics, we identify fan-shaped body local neurons called h∆C that receive input from this odor pathway and a previously described wind pathway. We show that h∆C neurons exhibit odor-gated, wind direction-tuned activity, that sparse activation of h∆C neurons promotes navigation in a reproducible direction, and that h∆C activity is required for persistent upwind orientation during odor. Based on connectome data, we develop a computational model showing how h∆C activity can promote navigation towards a goal such as an upwind odor source. Our results suggest that odor and wind cues are processed by separate pathways and integrated within the fan-shaped body to support goal-directed navigation.

Evaluation of tick control tube month of placement and modifications to increase visitation by small mammals

AbstractTick control tubes are a host‐targeted tick control method targeting immature Ixodes scapularis ticks attached to mice or found within mouse burrows and nests. Tick control tubes contain permethrin‐treated cotton inside cardboard tubes that mice use as nesting material. Ticks attached to mice or present in their burrows are exposed to the treated cotton. However, there have been variable results using these tubes for tick control. Rodent visitation and use of these tubes may influence their effectiveness. The aim of this study was to evaluate small mammal use of tick control tube cotton and to evaluate whether cotton size or odor attractants changed small mammal tube visitations and cotton removal. For the cotton size experiment, three different cotton sizes were used. In the odor attractant experiment, three different odor attractants were used (peanut butter, safflower oil, and vanillin) along with a commercially available tube as a control. A negative control group that had no cotton present in the tube was used for both experiments. Cotton loss was determined by weighing cotton in deployed tubes weekly, and mouse and nontarget species interactions were evaluated using camera‐trap data collected at each site. While the tested cotton sizes and odor attractants did not affect cotton use, mice did increasingly use cotton during cooler fall months, with the highest use of cotton in October and least use in July. These results suggest that mouse use of cotton was not related to cotton size or odor attractants but was dependent on season. This warrants future research on temporal small mammal use of tick control tubes to determine optimal deployment times for tick control.

Regulation of Sexually Dimorphic Expression of Major Urinary Proteins.

Male house mice excrete large amounts of protein in their urinary scent marks, mainly composed of Major Urinary Proteins (MUPs), and these lipocalins function as pheromones and pheromone carriers. Here, we review studies on sexually dimorphic MUP expression in house mice, including the proximate mechanisms controlling MUP gene expression and their adaptive functions. Males excrete 2 to 8 times more urinary protein than females, though there is enormous variation in gene expression across loci in both sexes. MUP expression is dynamically regulated depending upon a variety of factors. Males regulate MUP expression according to social status, whereas females do not, and males regulate expression depending upon health and condition. Male-biased MUP expression is regulated by pituitary secretion of growth hormone (GH), which binds receptors in the liver, activating the JAK2-STAT5 signaling pathway, chromatin accessibility, and MUP gene transcription. Pulsatile male GH secretion is feminized by several factors, including caloric restriction, microbiota depletion, and aging, which helps explain condition-dependent MUP expression. If MUP production has sex-specific fitness optima, then this should generate sexual antagonism over allelic expression (intra-locus sexual conflict) selectively favoring sexually dimorphic expression. MUPs influence the sexual attractiveness of male urinary odor and increased urinary protein excretion is correlated with the reproductive success of males but not females. This finding could explain the selective maintenance of sexually dimorphic MUP expression. Producing MUPs entails energetic costs, but increased excretion may reduce the net energetic costs and predation risks from male scent marking as well as prolong the release of chemical signals. MUPs may also provide physiological benefits, including regulating metabolic rate and toxin removal, which may have sex-specific effects on survival. A phylogenetic analysis on the origins of male-biased MUP gene expression in Mus musculus suggests that this sexual dimorphism evolved by increasing male MUP expression rather than reducing female expression.

Does scent attractiveness reveal women's ovulatory timing? Evidence from signal detection analyses and endocrine predictors of odour attractiveness.

Odour cues associated with shifts in ovarian hormones indicate ovulatory timing in females of many nonhuman species. Although prior evidence supports women's body odours smelling more attractive on days when conception is possible, that research has left ambiguous how diagnostic of ovulatory timing odour cues are, as well as whether shifts in odour attractiveness are correlated with shifts in ovarian hormones. Here, 46 women each provided six overnight scent and corresponding day saliva samples spaced five days apart, and completed luteinizing hormone tests to determine ovulatory timing. Scent samples collected near ovulation were rated more attractive, on average, relative to samples from the same women collected on other days. Importantly, however, signal detection analyses showed that rater discrimination of fertile window timing from odour attractiveness ratings was very poor. Within-women shifts in salivary oestradiol and progesterone were not significantly associated with within-women shifts in odour attractiveness. Between-women, mean oestradiol was positively associated with mean odour attractiveness. Our findings suggest that raters cannot reliably detect women's ovulatory timing from their scent attractiveness. The between-women effect of oestradiol raises the possibility that women's scents provide information about overall cycle fecundity, though further research is necessary to rigorously investigate this possibility.

Body Odours as Lures for Stoats Mustela erminea: Captive and Field Trials.

Simple SummaryThe stoat (Mustela erminea) is invasive in New Zealand and has a serious impact on native biota. Trapping is the most common technique used to control stoats, but efforts to eradicate them or to improve control efficiency will require a range of different techniques. We examined the use of mustelid body odours as lures to attract stoats to traps or monitoring devices. Stoats were attracted to stoat urine, scats, and bedding, and to ferret (M. furo) bedding in captive and field trials. The use of odour lures may be particularly useful when the usual food-based lures are ineffective.Eradication and control methods to limit damage caused to native biota in New Zealand by the stoat (Mustela erminea) rely on effective lures for trapping and detection devices, such as cameras. Long-life semiochemical lures have the potential for targeting stoats in situations where food-based lures are of limited success. The attractiveness of body odours of captive stoats was tested in a series of captive animal and extensive field trials to investigate their potential as trapping and monitoring lures. Stoats approached and spent significantly more time sniffing stoat urine and scats and bedding from oestrous female stoats than a non-treatment control. The bedding odours were attractive in both the breeding and the non-breeding season. Stoats also spent significantly more time sniffing oestrous stoat bedding than female ferret bedding, but the ferret odour also produced a significant response by stoats. In the field trials, there were no significant differences between the number of stoats caught with food lures (long-life rabbit or hen eggs) compared with oestrous female or male stoat bedding lures. These results indicate the potential of both stoat bedding odour and the scent of another mustelid species as stoat trapping lures that likely act as a general odour attractant rather than a specific chemical signal of oestrus.