Table 4. Effect of a multi-protease in the diet on carcass trait of broiler chickens1),2)

PC PC-150 NC NC-150 NC-300 ENC ENC-150 ENC-300 SEM p-value
Crude protein (%) - - −0.5 −0.5 −0.5 −1 −1 −1
Amino acid3) (%) - - −2 −2 −2 −4 −4 −4
Day 21
 Empty BW (%) 89.63 89.75 89.47 89.35 86.86 89.33 90.01 89.51 0.300 0.409
 Drumstick (%) 8.37 8.47 8.07 8.65 8.14 8.66 8.22 8.36 0.077 0.475
 Breast meat (%) 21.09abc 21.63ab 20.69bc 21.24ab 21.88a 20.16c 21.37ab 21.69ab 0.115 0.006
Day 35
 Empty BW (%) 91.49 90.87 91.08 91.08 91.05 91.8 91.39 91.70 0.135 0.756
 Drumstick (%) 8.49 8.13 8.44 8.53 8.09 8.30 8.40 8.56 0.098 0.945
 Breast meat (%) 24.82b 26.01a 24.54b 24.88b 26.06a 24.74b 25.94a 26.11a 0.114 < 0.001
The eight dietary treatments were: positive control (PC), negative control (NC: minus 0.5% from PC, and minus 2% of lysine, methionine, threonine and methionine plus cysteine), extreme negative control (ENC: minus 1% from PC, minus 4% of lysine, methionine, threonine and methionine plus cysteine), and plus multi-protease 150 or 300 g per ton (e. g., PC-150); PC, PC-150, NC, NC-150, NC-300, ENC, ENC-150, ENC-300.
Values are the mean of eight replicates per treatment.
List of amino acids: lysine, methionine, threonine and methionine + cystine.
Means with different superscripts in the same row were significantly different (Turkey’s multiple range test, p < 0.05).
BW, body weight.