Production records of 15 374 Holstein animals including pregnant heifers imported from several countries were analysed. The performance of imported heifers (a=5738) and their contemporaries (a=7967) was compared. The production of milk and protein of impo
Production records of 15 374 Holstein animals including pregnant heifers imported from several countries were analysed. The performance of imported heifers (a=5738) and their contemporaries (a=7967) was compared. The production of milk and protein of impo (en)