TABLE 2.

Performance of broiler chickens fed diets containing antimicrobials^a

Parameter	Period (days)	Value for control	Value for treatment with:					SEM	P valueb
			BBM	PEN	SAL	BAC	SAL + BAC
Body wt (g)	Initial	40.69	40.76	40.64	40.71	40.67	40.40	0.232	0.91
	0-14	457.31	459.89	462.87	441.32	451.67	458.77	7.224	0.38
	15-28	1,252.02	1,265.29	1,267.10	1,209.64	1,224.63	1,255.29	14.605	0.09
	29-35	1,815.09	1,811.42	1,805.12	1,783.69	1,776.75	1,825.11	27.805	0.80
Feed intake (g)	0-14	365.90	373.21	363.39	361.82	360.72	368.93	6.272	0.72
	15-28	896.23	906.58	868.70	861.47	870.33	901.47	15.969	0.27
	29-35	1,288.22	1,280.62	1,223.70	1,263.36	1,264.54	1,329.18	23.142	0.12
	0-35	3,215.03	3,237.87	3,084.20	3,118.83	3,125.57	3,239.98	47.916	0.14
Feed efficiency	0-14	1.21	1.22	1.17	1.24	1.21	1.20	0.014	0.09
(g of feed/g body wt gain)	15-28	1.78	1.77	1.69	1.76	1.76	1.77	0.018	0.06
	29-35	2.29	2.35	2.28	2.17	2.30	2.34	0.060	0.37
	0-35	1.78	1.79	1.72	1.75	1.77	1.78	0.015	0.04*
Total mortality (%)	0-35	5.48	12.64	7.12	12.77	7.65	4.47	2.682	0.26

^aValues indicate performance parameters of broiler chickens fed diets containing bambermycin (BBM), penicillin (PEN), salinomycin (SAL), bacitracin (BAC), and a salinomycin-bacitracin combination (SAL + BAC) at concentrations specified in Materials and Methods.

^bP values were obtained by analysis of variance. *, values are statistically different (P < 0.05).