The estimated genetic parameters and their standard deviations (SD) under different models*.

*All the models are performed with original hip score and different transformations of the elbow score. The transformations include Log, square root (SQRT) and inverse (INV). In each transformation of elbow score, the hip score remains the status of original score. The model of Original (O) was performed on the original scores on both hip and elbow. BLM (O) means the bi-variate linear model with original hip and elbow conformation scores as observations; BLM (LOG) means the bi-variate linear model with original hip conformation scores and log transformations for elbow scores as observations; BLM (SQRT) means the bi-variate linear model with original hip scores and square root transformations for elbow scores as observations; BLM (INV) means the bi-variate linear model with original hip scores and inverse transformations for elbow scores as observations. is the additive genetic variance, is the variance of combination effects of test year and test month, is the residual variance, is the phenotypic variance, is the heritability, subscript 1 means the trait of hip joint conformation scores, subscript 2 means the trait of elbow joint conformation scores. is the additive genetic covariance between these two traits, is the residual covariance between them, is the additive correlation between them, is the residual correlation between them.