Crossbreeding in dairy cattle – Results from a practical farm

Crossbreeding was practised in an originally purebred Holstein (HOL) dairy herd on an organic farm in Brandenburg. Bulls of the breeds Swedish Red (SRB) and Brown Swiss (BS) were used. Data made available covered calving years 2003 till June 2008. Data on first lactations originated from 481 HOL purebreds, 117 SRB x HOL crosses, 99 BS x HOL crosses, as well as 56 HOL x (SRB x HOL) and 28 HOL x (BS x HOL) back-crosses. For the second lactation 429 HOL, 94 SRB x HOL, 74 BS x HOL, and 31 HOL x (SRB x HOL) could be included. Back-crosses with Brown Swiss were not available for second lactations since this cross had been carried out at a later stage. The results for production traits (protein yield per day) showed highest values for the two first crosses SRB x HOL and BS x HOL (0.72 kg per day). However, SRB x HOL crosses had the highest cell counts. For second lactations, production was highest for BS x HOL while SRB x HOL trailed BS crosses as well as HOL purebreds. An analysis with respect to individual bulls revealed drastic differences in rank when comparing the estimated breeding values on the purebred basis with the average of the daughters on the farm. For functional traits, especially for those measured within first lactation, crosses were superior in fertility. For SRB crosses, also stillbirth rates were lower than for all other genotypes while survival was higher. However, BS crosses equalled Holsteins for stillbirths and survival. Although the data analysed here originates from a practical farm and does not stem from a planned experiment, the data appears to be useful to point to tendencies. Further analyses, especially with respect to a possible specific combining ability of individual bulls, seem to be necessary.

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