"In order to control the calving interval, and therefore to optimise milk production and maximise offspring in dairy cattle, artificial insemination (AI) is widely used. Currently, the conception rate of AI varies from 30% to 70%, the most critical aspect of successful conception being the timing of the insemination. Highest conception rates are achieved when the insemination is done 8 to 12 hours after the start of estrus (also known as “standing heat”). The right timing of AI, therefore, is related to detection of estrus in a cow. The BOVINOSE project aims to develop an “electronic nose” to detect estrus in a dairy cow, and thus to determine the optimal timing of artificial insemination. The physical principle is based on detection of sex pheromones that are exclusively secreted by the cow during estrus. These pheromones are the natural olfactory signal for the bull that the cow is in heat. Simply put, in essence, the device to be developed will mimic the bull’s nose. To this end the info-chemicals that make up the sex pheromones in cows will be investigated, a set of sensors for detection of these sex pheromones (or mix thereof) will be researched, and a functional prototype, consisting of a probe, an array of sensors and dedicated, integrated software for control and user-interaction will be developed and tested in field trials. The impact of the project is high, tapping the dairy farming market, which consists of some 1,700,000 farmers in the EU-27, producing about 135 Billion Kg milk annually. Preliminary investigations show that a selling price of € 1,800 would be economically attractive to the entire SME supply chain, providing an overall estimated profit of 10%-25% (depending on batch size). A sales price of € 1,800 would imply an attractive 15 months payout time for the dairy farmer (end user) with a herd of 60 cows, based on costs savings related to higher AI conception rate from 50% average to 60% (conservative estimation)."