Abstract #278

# 278
Estimation of genetic parameters for young stock survival in Danish beef × dairy crossbred calves.
R. B. Davis*1, E. Norberg3,2, A. Fogh1, 1SEGES, Aarhus N, Denmark, 2Aarhus University, Tjele, Denmark, 3NMBU (Norwegian University of Life Sciences), Ås, Norway.

Calf mortality leads to economic losses for the farmer and is an animal welfare issue. Currently, only calf mortality within the first 24 h is accounted for in the Danish breeding goal for beef x dairy calves. However, survival throughout the rearing period is also of upmost importance. Therefore, the aim of this study was to estimate genetic parameters for young stock survival, to evaluate if it is feasible to implement such a trait. Data on 90,926 crossbred calves was extracted from the Danish Cattle Database and was provided by the Danish research center, SEGES. Two traits were defined, young stock survival from 1 to 30 d and 31–200 d after birth. The traits were analyzed with a univariate animal model using the AI-REML algorithm in the DMU package. The model contained a fixed effect of year × month of birth, herd, sex, breed combination, parity of the dam, transfer and a random effect of the calf and herd × year. The pedigree was traced back 5 generations, for both the sires and dams. Results showed low but significant heritabilities (0.045–0.075) for both survival traits. Breeding values were calculated using DMU4. Breed combinations with Belgium Blue cattle sires outperformed all other sire breeds. The lowest survival rates were found for breed combinations with Jersey dams or Blonde d’Aquitaine sires. Sufficient genetic variation between sires for young stock survival was found. The breeding values of the sires had an effect on young stock survival that ranged from −2.5 to 3.5% and −5.4 to 4.7% for survival from 1 to 30 d and 31–200 respectively. It is therefore feasible to implement young stock survival traits in a genetic evaluation for beef × dairy crossbred calves. This will increase the survival rate of the calves and hereby increase animal welfare and decrease economic loss for the farmers.

Key Words: young stock survival, beef × dairy, genetic parameter