By regression analysis of data from 80 check samples from the Associat
ion of American Feed Control Officials and applying the least-squares
cubic method to the problem of statistical errors in both variables, i
t was determined that the best linear relation between the percent cru
de fiber value of a feed and the corresponding percent acid-detergent
fiber value is crude fiber (%) = 0.77 x acid-detergent fiber (%) - 0.4
9.