Method to monitor the precision of milk yields recorded at individual milking stalls on 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 Improvement Association (DHIA) for testing purposes and by farmers to monitor herd performance. Despite the importance of these data, little effort has been made to monitor the function and reliability of milking stalls and recording equipment on a daily basis. Described is an algorithm that allows for continuous monitoring of the function of individual milking stalls. The basis of the algorithm is the comparison of milk yield of individual cows over a period 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 ratios 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 1 by more than 5% are assumed to be malfunctioning. This algorithm was implemented as a computer program and was used to identify 3 malfunctioning stalls out of 12 at the USDA dairy facility (Beltsville, MD). The algorithm can easily be incorporated into existing management programs or used as a separate program. In either case, routine use of this algorithm can improve the reliability of DHIA test programs and potentially reduce the incidence of new mastitis infections by enabling detection of malfunctioning milking equipment.
Lefcourt
A M
AM
Agricultural Research Service, USDA, Livestock and Poultry Sciences Institute, Beltsville, MD 20705, USA.
D000818:Animals; D001322:Autoanalysis; D002417:Cattle / Q000502:physiology*; D003612:Dairying / Q000379:methods*; D005260:Female; D007774:Lactation; D011996:Records; D012680:Sensitivity and Specificity