Table 5.

Nitrogen balance in pigs fed diets with either antibiotics or increasing levels of BA^1,2

		BA, %				P value
Item3	PC4	0.00	0.50	1.00	SEM	PC vs. 0.00	Linear5	Quadratic6
Initial BW, kg	12.6	11.9	12.2	11.9	0.7	0.464	0.962	0.704
ADFI, g/d	602	575	587	576	26	0.461	0.958	0.715
Dry matter
Intake, g/d	540	515	526	517	23	0.461	0.958	0.715
Fecal output, g/d	78	81	77	72	10	0.645	0.240	0.908
Digestibility, %	85.6	84.1	85.3	86.0	1.8	0.309	0.177	0.877
Nitrogen
Intake, g/d	18.3	17.4	17.8	17.5	0.8	0.451	0.954	0.695
Fecal output, g/d	3.4	3.6	3.3	3.0	0.5	0.619	0.124	0.907
Urine output, g/d	4.6	4.2	4.1	3.3	0.6	0.584	0.306	0.621
Digestibility, %	81.3	79.1	81.5	82.6	2.8	0.308	0.096	0.710
Retention, %	55.6	54.2	57.9	63.4	3.4	0.764	0.046	0.812

¹The experimental unit was a pig, and each least squares mean represents 10 observations, except for 1.00% BA, which have 11 observations.

²Pigs were housed individually in metabolism crates for this study.

³BW = body weight; ADFI = average daily feed intake.

⁴PC = a basal diet with antibiotics (chlortetracycline at 100 mg/kg [450 mg/kg of Aureomycin 100] during phases 1 to 3, and tylosin at 44 mg/kg [200 mg/kg of Tylan 100] during phases 4 to 6).

⁵Linear = linear effect of increasing levels of BA.

⁶Quadratic = quadratic effect of increasing levels of BA.