Shared volatile organic compounds between camel metabolic products elicits strong Stomoxys calcitrans attraction.

The sources of animal odours are highly diverse, yet their ecological importance, in host-vector communication, remains unexplored. Here, using the camel (host)-Stomoxys calcitrans (vector) interaction, we collected and analyzed the Volatile Organic Compounds (VOCs) of camels from four of its different odour sources: breath, body (skin), urine, and dung. On non-metric model multivariate analyses of VOCs we show that substantial chemo-diversity exists between metabolic products associated with an individual camel. VOCs from the four metabolic products were distinct and widely segregated. Next, we show electrophysiologically, that VOCs shared between metabolic products activated more Olfactory Sensory Neurons (OSNs) and elicited strong behavioural attractive responses from S. calcitrans under field conditions independent of geography. In our extended studies on house flies, the behavioural response to these VOCs appears to be conserved. Overall, our results establish that VOCs from a range of metabolic products determine host-vector ecological interactions and may provide a more rigorous approach for discovery of unique and more potent attractants.