BLUP Base for Dairy Cattle Genetic Improvement in Thailand

The breeding value was estimated from grade Holstein Friesian for milk yield at 305 days (305MY), percent fat (FP), and total fat yield (FY) in kilogram. Animals were raised under Thai small farm conditions each of 10 to 30 heads per household. The data were collected during the years 1972 to 1998 from the joint cooperation between Kasetsart University (KU) and the Dairy Farming Promotion Organisation of Thailand (DPO). The BLUP procedure was employed through sire model, animal model and repeatability models. The data analysis in each trait was made for only additive gene effect by univariate basis. The first phase of analysis (1972-1991) used sire and animal model whereas the second phase (1991-1998) used animal and repeatability models. The phenotypic correlation between 305MY and FP, and 305MY and FY were found to be between .80 to .99 and –.11 to .13. The corresponding genetic correlation of these three traits were ranged between .40 to .70 and .09 to .15, accordingly. The phenotypic and genetic trend were analysed by regressing the solutions of year of calf birth and year of sire birth on year. The phenotypic trend of 305MY, FP, and FY were ranged between 31.3 to 33.4 kg, -.002 to -.012 %, and 1.12 to 2.40 kg per year per. The genetic trend of the corresponding traits were ranged between –88.02 to 45.6 kg, -.06 to -.02 %, and -1.03 to .29 kg per year, accordingly.