Table 2.

Effect of dietary keratinase on growth performance of broilers.¹

Items	Control	100,000 U/kg keratinase	200,000 U/kg keratinase	P valuelinear	P valuequadratic
Day 1–21
Body weight gain, g	743 ± 60	758 ± 63	785 ± 46	0.123	0.304
Feed intake, g	1055 ± 61	1066 ± 56	1051 ± 49	0.887	0.830
Feed conversion ratio, g/g	0.70 ± 0.21b	0.71 ± 0.26b	0.75 ± 0.24a	0.002	0.003
Day 22–42
Body weight gain, g	1621 ± 58a	1635 ± 80ab	1680 ± 51b	0.061	0.151
Feed intake, g	2825 ± 173	2868 ± 132	2894 ± 92	0.625	0.342
Feed conversion ratio, g/g	0.58 ± 0.02	0.57 ± 0.02	0.58 ± 0.02	0.528	0.521
Day 1–42
Body weight gain, g	2364 ± 04a	2393 ± 23ab	2465 ± 68b	0.042	0.116
Feed intake, g	3880 ± 225	3934 ± 181	3945 ± 117	0.443	0.717
Feed conversion ratio, g/g g/g	0.61 ± 0.01b	0.61 ± 0.01b	0.62 ± 0.01a	0.026	0.036

¹Values are means ± SD, n = 9. Means in a row with different superscript letters are different, P < 0.05.