Anoestrus in dairy cows: causes and solutions

Anoestrus is a commonly found symptom in dairy cows caused by physiological and pathological factors. As to the latter, one can differentiate between acyclicity (ovarian dystrophy, ovarian cysts, endometritis/pyometra with a persistent corpus luteum) and silent heat (anaphrodisia). Numerous underlying factors for anoestrus have been described such as severe negative energy balance postpartum, high milk yield, age, breed, season, stress, other diseases, i.e. endometritis and lameness. Analysis of anoestrus as a herd problem is challenging as it is not only influenced by cow related factors but also by the quality of oestrus detection and housing (i.e. type of floor). Therapeutic measures in terms of hormonal treatment are possible. However, treatment success is very variable from farm to farm and from animal to animal, and therefore, is often not satisfactory and a solution for the problem. In conclusion, in order to control anoestrus as a herd problem, a systematic analysis of underlying factors for anoestrus is necessary with respective corrective measures.