Dietary factors, in addition to type of grain, include
energy density and fiber concentration. Paulicks et al.
(2000) found that ADG increased and feed conversion
improved in response to K-diformate on lower-energy
diets compared with diets approximately 5% greater in
energy density. Improved apparent ileal digestibility of
Lys, due to decreased endogenous Lys flow, was observed
in growing pigs on by-product-based diets (219
g of NDF/kg of DM) but not on barley-based diets (188
g of NDF/kg of DM; Partanen et al., 1998). The differing
fiber content of the diets could be a factor; however, the
difference was small. A later study by Partanen et al.
(2002) using high- (240 g of NDF/kg of DM) or medium-
(188 g of NDF/kg of DM) fiber diets in growing-finishing
pigs showed no effect of dietary fiber on performance
response to additives. In this study, feed conversion
ratio was improved in the growing and finishing period
for pigs on formic acid-ammonium formate-treated
diets.