Method to monitor the precision of milk yields recorded at individual milking stalls on a daily basis

Automated systems to record individual milk weights of cows at each milking are now common on dairy farms. These data are used by Dairy Herd Improveme nt Association (DHIA) for testing purposes and by farmers to monitor herd p erformance. Despite the importance of these data, little effort has been ma de to monitor the function and reliability of milking stalls and recording equipment on a daily basis. Described is an algorithm that allows for conti nuous monitoring of the function of individual milking stalls. The basis of the algorithm is the comparison of milk yield of individual cows over a pe riod of days. For each cow, milk production at a selected Stall is compared with production of that same cow when milked at any other stall. These rat ios are averaged across all cows milked at least once in the selected stall and once at any other stall. Ideally, the mean ratio for each stall should be 1. Stalls where the mean ratio deviates from I by more than 5% are assu med to be malfunctioning. This algorithm was implemented as a computer prog ram and was used to identify 3 malfunctioning stalls out of 12 at the USDA dairy facility (Beltsville, MD). The algorithm can easily be incorporated i nto existing management programs or used as a separate program. In either c ase, routine use of this algorithm can improve the reliability of DHIA test programs and potentially reduce the incidence of new mastitis infections b y enabling detection of malfunctioning milking equipment.