Table 5.

Blood analytes of newly received feedlot calves-fed diets containing different roughage levels (wheat hay; 30% or 60%; DM basis) and supplemental fat (yellow grease; 0 [−FAT] or 3.5% [+FAT]; DM basis)

Item1	Roughage level		Supplemental fat		SEM2	P-value
	30%	60%	−FAT	+FAT		Roughage	Fat	Roughage × Fat
Pens (steers)	12 (36)	12 (36)	12 (36)	12 (36)	-	-	-	-
Days on feed	58	58	58	58	-	-	-	-
Blood analytes
Plasma cortisol, ng/mL	17.1	18.5	16.2	19.5	1.58	0.42	0.07	0.23
Plasma haptoglobin, ng/ mL	0.44	0.33	0.33	0.43	0.050	0.09	0.13	0.92
Plasma immunoglobulin-G, g/L	28.0	29.2	27.1	30.0	1.20	0.49	0.09	0.70
Plasma tumor necrosis-α, pg/ mL	67.2	70.5	68.0	70.0	1.75	0.13	0.44	0.38
Plasma interleukin-6, pg/mL	7.30	7.23	7.50	7.06	0.31	0.86	0.37	0.84
Plasma glucose, mg/dL	81.3	79.5	81.1	79.7	2.82	0.57	0.65	0.97
Plasma urea nitrogen, mg/dL	11.0	11.1	11.1	10.9	0.20	0.73	0.57	0.30
Serum antibody titers
Bovine viral diarrhea virus-1	0.875	0.845	0.870	0.851	0.113	0.84	0.90	0.30

¹ Plasma Immunoglobulin-G, plasma tumor necrosis-α, and plasma interleukin-6 were analyzed on days 0 and 7. Plasma cortisol, haptoglobin, glucose, and urea nitrogen, and serum antibody titers were analyzed on days 0, 7, 14, 28, and 58. Serum concentrations of antibodies against bovine viral diarrhea virus (BVDV) were reported as sample:positive control ratio (Gonda et al., 2012).

² Standard error of the mean.