Accuracy of Part-Time Trapnesting on an Individual and Family Basis

PART-TIME trapnesting is a laborsaving practice of considerable importance to the poultry industry. Although the practice is economical, its widespread adoption and value are dependent primarily upon the accuracy with which it measures the actual daily trapnest record of the birds. Most previous publications have dealt with the accuracy of estimating yearly egg records for individual pullets from samples of their production during periods which included 1 to 6 days per week. The report of Nordskog and Crump (1948), however, shows that the dependability of such part-time records differs according to the number of days trapnesting is practiced and the size of family groups under test. Nordskog (1948) also has contributed valuable computations showing the relative breeding progress to be expected with different combinations of variations in (1) family size, (2) proportion of time trapnested, and (3) degree of heritability of egg production. He stated that “little is gained from . . .