Prevalence and preliminary analisys of severe Udder Edema occurrence in Italian Friesian cows

Udder edema is caused by an excessive accumulation of lymphatic fluid in the interstitial spaces of udder, leading to alterations of appearance, consistency and flexibility and increasing the risk of physical damage. The present study aimed to investigate the prevalence of severe udder edema (SUE) in Italian Friesian cows and to analyse the relevance of some possible risk factors of SUE occurrence. Data were from a program currently running in cooperation with some breeder associations and aimed to control dairy cows for functional and health traits. A total of 8,734 udder edema observations was evaluated after calving on 4,666 cows in 46 herds of northern Italy as alternatively severe (all quarters and navel and extending to the upper half of udder over the midline) or not severe. Overall prevalence of SUE approached 9,1% and appeared higher in primiparous than in multiparous cows (11,4 vs 8,5%, respectively). Risk of occurrence of SUE was investigated using logistic regression analysis and considering the role of herd, calving year and season, parity, cow genetic merit and the concurrent occurrence of retained placenta. To be in the first parity and to have a high genetic merit for milk yield appeared associated with an increased risk of SUE. Further research is needed for better understanding the genetic aspects of such disorder.