What is a semio-chemical ?

What is a semio-chemical ?

Semiochemistry is the chemical means of communication used by living species.

The identification of chemical signals used by animals throughout their life has allowed scientists to develop and perfect new therapeutic and zootechnical instruments that respect man, animals and the environment.

Research carried out by IRSEA (Institute of Research in Semiochemistry and Applied Ethology), as evidenced by the 79 international patents filed since the founding of the institute, has been the subject of numerous international publications and communiqués.

There are several categories of semiochemicals :

Pheromones: Chemical substances that create a specific behavioral response in a fellow creature when emitted into the environment in infinitesimal doses.
Pheromones may be contained in urine, sweat or excrement, or emitted by specialized glands. Disseminated in the air (female peacock at night) or affixed on a support (wolf urine on a tree), they are detected in infinitesimal doses by an animal of the same species, who will often track down the source of the chemical signal from a distance. The main functions of pheromones are to mark territory, attract creatures of the opposite sex, or send out an alert signal in the event of attack (minnow). Pheromones are also used as a biological weapon to fight harmful insects.

The existence of pheromones in the vegetal world has also been proven (reproduction pheromones in algae, alert pheromones in trees that have been defoliated by herbivorous animals).

Allelochemicals (allomones and kairomones) are a means of communication between individuals of different species.

Allomones are chemical substances which provide an advantage for animals that produce them. A remarkable allomone is secreted by the Coleoptera Staphylinidae Pella laticolis, which presents a particular predation behavior towards ants of the species Lasius fuliginosus. At the sight of an ant, the Coleoptera moves forward and shows its secretory glands. These glands secrete a substance inhibiting the ant’s combativeness. The Coleoptera takes advantage of this hesitation time to jump on its prey and kill it.

Kairomones are chemicals substances which provide an advantage to individuals that intercept them. Many parasites, such as ticks, use kairomones to locate their host. The female tick, settled on branches of bushes or at the extremity of tall weeds, waits for a mammal to pass by. As soon as it perceives butyric acid emanating from the sebaceous glands of the mammal’s skin, it lets itself fall onto its future host, moves towards the epiderm and perforates it. Then the tick puts its head in the epiderm and gorges itself with warm blood.

Semiochemicals (pheromones, allomones and kairomones) are thus essential for number of arthropods in order to communicate
during reproduction, during the localization and the capture of their prey or during the detection of their host. The IRSEA develops analogs of semiochemicals, which confuse this communication to fight against parasites or so-called “harmful” animals. This strategy prevents the use of commonly utilized toxic chemical products and provides, as required, preventive or curative solutions.