| The objective of this work was to evaluate milk production of a Holstein × Zebu herd managed on a semiintensive system at Estação Experimental Joaquim Távora, IAPAR, in the northeastern region of Paraná - Brazil. Two hundred and seventeen records on milk production per lactation period (MY), milk production up to 305 days of lactation (MY305) and length of lactation period (LL) of 82 crossbred cows varying in breed composition were analyzed according to a linear statistical model that included the fixed effects of breed composition, season and year at onset of lactation, order of parturition and place of birth, in addition to the experimental error. Cows born in Joaquim Távora had longer lactation periods and produced more milk than cows born in Ibiporã.... |
