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Five methods of adjusting the sire's daughter average, namely: (I) the actual herd average and herd-mate averages for (II) annual lactation, (III) six-month season, (IV) seven-month rolling season, and (V) annual actual age group, were compared with the simple daughter average (VI). Measures II, III, and IV were the ME averages of all nonpaternal herd-mates freshening in the designated periods. The highest six-month period based on month of freshening was November through April.
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Gaunt et al. (1964) studied this question.
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