Table 2.

Summary of feed intake and performance data for high and low RFI animals (n = 9 bulls, n = 8 heifers)

Trait	Bulls			Heifers			P d
	High RFIa	Low RFI	SDf	High RFI	Low RFI	SD	RFI	Ge	RFI × G
DMI, kg/d	10	8.9	1.08	9.4	8.8	0.6	0.0025	0.28	0.309
RFI, kg DM/d	0.59	−0.5	0.58	0.42	−0.55	0.5	< 0.0001	0.29	0.34
MMBW0.75, kgb	97.01	97.04	8.64	93.39	93.5	4.06	0.87	0.2	0.79
Initial BW, kg	388.5	382.16	54.91	375.8	364.5	32	0.5	0.62	0.95
Final BW,kg	516.05	508.6	54.28	460.8	458.4	36.1	0.75	0.011	0.82
ADG, kg	1.82	1.8	0.33	1.2	1.3	0.4	0.68	0.001	0.62
Backfatchangec, mm	1.45	2.01	0.69	1.17	1.46	0.72	0.18	0.14	0.62

DMI Dry matter intake, RFI Residual feed intake, ADG Average daily gain, MMBW Midtest metabolic body weight

^aHigh RFI is feed inefficient and low RFI is feed efficient

^bMetabolic BW^0.75, kg is determined as BW^0.75 in the middle of the RFI measurement period which was estimated from the intercept and slope of the regression line after fitting a linear regression line through all metabolic BW (BW^0.75) observations

^cBack fat change is mean of fat depth at endminus mean of fat depth at start of the feed intake recording period

^dP P-value

^eG Gender

^fSD Standard Deviation