Projection Factors for Goat Lactation Records

Abstract

Projection factors based on production on the last day of sampling were developed for dairy goat milk and fat records. The 305-day lactation was divided into 13 stages varying from 10 to 40 days. The shortest stages were in early lactation. Sets of factors were developed for four ages at freshening, two seasons, two levels of herd production, and two breed groups. These classifications were necessary to avoid bias and improve accuracy. Cumulative yield factors also were developed with the same grouping of records. These factors are used when production for the last sample day is not available © 1979, American Dairy Science Association. All rights reserved.