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Heritabilities for egg number, egg weight, and eggshell color (percentage light absorbance) at 39 wk of age, and the genetic correlations between them were estimated by restricted maximum likelihood in three Catalan poultry breeds: Penedesenca Negra (PN), Prat Lleonada (PL), and Empordanesa Roja (ER). Additive genetic differences between these breeds were also estimated. Data were from the IRTA Poultry Genetic Conservation Program and consisted of records from 1,309 PN, 1,466 PL, and 1,440 ER hens, which were obtained from 80 contemporary batches per breed hatched between 1987 and 1992. Estimates of heritability for egg number, egg weight, and eggshell color were, 0.20, 0.59, and 0.49 for PN, 0.31, 0.48, and 0.53 for PL; and 0.33, 0.50, and 0.27 for ER. Estimated genetic correlations between egg number and egg weight, egg number and shell color, and egg weight and shell color were, for …