Table 2.

Effect of betaine (Bet) supplementation on growth performance in broilers.¹

	Low CP		High CP			CP		Bet		P-value
Items	Bet 0	Bet 0.12%	Bet 0	Bet 0.12%	SEM2	Low	High	0%	0.12%	CP	Bet	CP × Bet
1–21 d
BWG3, g	682	680	695	704	9.25	681	688	689	692	0.2059	0.2059	0.1960
FI4, g	1098	1093	1101	1102	8.42	1096	1097	1100	1098	0.2342	0.3533	0.7899
FCR5	1.61	1.61	1.58	1.57	0.02	1.61	1.60	1.60	1.59	0.5268	0.4411	0.1055
22–42 d
BWG, g	1913	1941	2203	2109	18.15	1927	2156	2058	2025	0.0187	0.7128	0.2666
FI, g	3789	3851	3849	3726	16.75	3820	3788	3869	3789	0.4096	0.4875	0.6261
FCR	1.98	1.98	1.75	1.77	0.02	1.98	1.76	1.88	1.87	0.0048	0.3753	0.5353
1–42 d
BWG, g	2595	2621	2898	2813	20.48	2608	2856	2747	2717	0.0062	0.8540	0.1094
FI, g	4887	4944	4950	4828	21.76	4916	4889	4919	4886	0.3126	0.4080	0.8011
FCR	1.88	1.89	1.71	1.72	0.02	1.89	1.71	1.79	1.80	0.0002	0.1583	0.1539
Mortality, %	6.3	6.8	7.4	6.7	1.26	6.6	7.1	6.9	6.8	0.4595	0.7725	0.6258

¹Low crude protein (CP) diet, 21 and 18% CP, 0.45 and 0.34% methionine for starter and finisher periods; high CP diet, 23 and 20% CP, 0.50 and 0.38% methionine.

²Standard error of means.

³Body weight gain.

⁴Feed intake.

⁵Feed conversion ratio.