SPP1 and Osteochondrosis: In this study, a significant association of sequence variants of CALCR, PTH1R, SPP1, and VDR with serum parameters was not observed, even though CALCR has been associated with leg locomotion traits (Fan et al. 2009) and bone integrity (Alexander et al. 2010), and PTH1R has been associated with osteochondrosis lesions in pigs (Rangkasenee et al. 2013).