Table 3.

Significance tests for fixed sources of variation for carcass traits in feedlot cattle by type of bovine respiratory disease (BRD) measurement used

Item1	n	Feedlot cattle–model fixed effect2
TRT	CG	SD(CG)	Sex	AgeS
BRD incidence
HCW	3,184	<0.01	<0.01	<0.01	<0.01	<0.01
LMA	3,184	0.22	<0.01	<0.01	<0.01	<0.01
Fat	3,184	<0.01	<0.01	<0.01	<0.01	0.02
MarbS	3,184	0.04	<0.01	<0.01	<0.01	<0.01
NoTrt
HCW	3,184	<0.01	<0.01	<0.01	<0.01	<0.01
LMA	3,184	0.13	<0.01	<0.01	<0.01	<0.01
Fat	3,184	<0.01	<0.01	<0.01	<0.01	0.02
MarbS	3,184	<0.01	<0.01	<0.01	<0.01	<0.01

¹BRD incidence = untreated (100) vs. treated (200); NoTrt (number of treatments): 100 = nontreated cattle, 200 = cattle treated once, 300 = cattle treated twice, 400 = cattle treated 3 or more times; LMA = LM area; fat = subcutaneous fat cover; and MarbS = marbling score.

²TRT = BRD incidence or NoTrt; CG = contemporary group; SD(CG) = final slaughter date within contemporary group; sex = steer or heifer; and AgeS = day of age at slaughter.