Table 4.
Multiple linear regression equations adjusted with body weight at d 7, 21, and 28-d-old broilers to predict the days to achieve 1.5 kg body weight^1,2

Item	Prediction equation	Predicted days to achieve 1.5 kg BW
C	y = 1.3189x2 + 24.295x — 52.51	26.34
T1	y = 1.1581x2 + 27.487x — 66.18	26.79
T2	y = 1.2529x2 + 26.229x — 62.64	26.39
T3	y = 1.2056x2 + 25.734x — 55.90	26.83
T4	y = 1.1687x2 + 27.152x — 64.57	26.84
SEM3		0.239
P-value		0.255

Data are expressed as means of six replicates per dietary group.
Control diet, balanced diet; T1, diet with reduction of 100 kcal ME/kg and 1% of CP and addition of 4,000 μ/g xylanase, 400 μ/g α-amylase, and 8,000 μ/g protease; T2, diet with reduction of 100 kcal ME/kg and 1% of CP and addition of 800 μ/g β-mannanase; T3, diet with reduction of 100 kcal ME/kg and 1% of CP and addition of 2,200 μ/g xylanase and 200u/g β-glucanase; T4, diet with reduction of 100 kcal ME/kg and 1% of CP and addition of 1,000 μ/g xylanase.
SEM, standard error of the mean.