The objective of this study was to determine whether there are differences in prececal amino acid digestibility between commonly used slow- and fast-growing broiler strains when the regression approach is applied. A slow- and fast-growing broiler strain was selected and provided experimental diets with soybean meal included at levels of 0, 100, and 200 g/k ad libitum consumption. Each treatment was tested with six pens comprising 10 birds each. Digesta samples were collected on a pen basis and prececal amino acid digestibility of soybean meal was calculated by linear regression.

The results indicated that the prececal crude protein and amino acid digestibility of soybean meal did not differ significantly between strains; the values were numerically almost identical. The results of this study provide evidence of the transferability between broiler strains of prececal amino acid digestibility data, determined using the regression approach, thus improving the accuracy of diet formulation without drawbacks.