The estrous cycle of the cow is driven by complex hormonal changes that manifest in organs, glands, and behavior. This material explains the physiological processes, illustrates them with diagrams of follicle and corpus luteum development, and describes the typical signs of estrus. Practical guidelines help determine the optimal time for insemination. In addition, factors influencing the success of artificial insemination are highlighted – from careful observation of heat symptoms to overall management conditions. With comments by Helmut Demmelhuber on a professional article from “Guide: Cattle Insemination” by Elite/top agrar (2025): https://www.elite-magazin.de