The impact of pre-dry-off weather patterns on subsequent lactation udder health in dairy cows, and their comparison with milkability, milk quality and udder health parameters - A pilot study

Environmental conditions are known toinfluence the dairy cow health, with most research focusing onthe detrimental effects ofheat stress. However, the impact ofnon-summer weather patterns intemperate climates onudder health carry-over between lactations isnot well understood. This pilot study evaluated the effect ofvarious weather factors (temperature, humidity, precipitation, sunshine) during 1-day to90-day periods before dry-off onudder health inthe first month post-calving (represented bysomatic cell count, conductivity, lactose, and mastitis incidence) in199 Holstein cows inCentral Europe. The scope ofthe experiment was limited toone farm and one year ofobservations. Moreover, wealso evaluated milk quality, milkability, and udder health parameters during the same periods before dry-off onudder health after calving. Weaimed toidentify viable indicators across available automatically collected data from weather stations and milking parlour analysers. Wefound that the long-term (30- to90-day) exposure tocolder temperatures, high humidity, and low sunshine duration before dry-off was significantly associated with worse udder health after calving. Incontrast, short-term weather conditions (1- to7-day) had nosignificant effect. Monitored milk quality and udder health parameters showed asignificant relation toudder health after calving during the immediate periods before dry-off, while milkability parameters were insignificant. If lactose was decreased orprotein content, conductivity, and somatic cell count were elevated during the 1- and 7-day period before dry-off, cows after calving showed worse udder health. These findings identify prolonged cold and damp conditions asasignificant environmental risk factor for poor udder health inthe subsequent lactation, expanding our understanding beyond the conventional focus onheat stress.