Simultaneous estimation of the covariance structure of field and station test traits in Slovakian pig populations

The (co)variance matrices and genetic parameters for five production traits in pigs were estimated for breeds White Improved (WI) and White Meaty (WM) in Slovakia. The field test traits ultrasonic backfat (BFFT) and average d aily gain (ADGFT) measured oil boars and gilts at farms (1992-1995) and ave rage daily gain at station (ADGST), percentage of valuable cuts (VC) and ba ckfat thickness (BFST) measured at the stations during the period 1986-1995 were used in this analysis. A completely random animal model (except the f ixed SEX effect) with different models for different traits was used to est imate 48 (co)variance components using VCE program separately for each bree d. The heritabilities calculated as ratios of variance estimations were 0.3 3 (BFFT), 0.13 (ADGFT), 0.23 (ADGST), 0.50 (VC). 0.39 (BFST) for WI breed a nd 0.26 (BFFT), 0.16 (ADGFT), 0.19 (ADGST), 0.43 (VC), 0.28 (BFST) for the smaller breed WM. The genetic correlations between daily gain at field and station were 0.42 and 0.67 for WI and WM breed and 0.53 and 0.49 for backfa t at the field and station test. Rather high values (around 0.30) of valian ce ratios for herd x year x season for field test traits BFFT and ADGFT wer e found.