Estimates from BP methods and TIM were compared with actual milk yields for a wide range of milk recording frequencies to determine which method was more accurate for estimating lactation yield. Measures of accuracy were correlations between actual and estimated yields and standard deviations of differences between actual and estimated yields. Of particular interest was the determination of the accuracy of the methods for test plans in which milk weights or component samples were not collected on each milking on the test day or were recorded less frequently than once per month. This study included testing environments for cows on 1) traditional monthly( MN) testing (i.e., herds for which milk weights are taken approximately 1 d/mo), 2) a.m.–p.m. ( AP)testing (i.e., herds for which only one of the two milk weights is recorded on the monthly test date), and 3)trimonthly ( TRI) testing (i.e., herds for which weights are taken 1 d every 3 mo). The estimates from the TIM and BP methods were compared with two measures of actual milk yield within each testing environment
Comparison of Test Interval and Best Prediction Methods for Estimation of Lactation Yield from Monthly, a.m.–p.m., and Trimonthly Testing (PDF Download Available). Available from: https://www.researchgate.net/publication/13221765_Comparison_of_Test_Interval_and_Best_Prediction_Methods_for_Estimation_of_Lactation_Yield_from_Monthly_am-pm_and_Trimonthly_Testing [accessed May 8, 2016].