Two hundred ten weanling pigs (initially 12.4 lb and 18 ± 2 d of age) were used in a
14-d growth assay to determine the influence
of various lactose sources and levels on nursery pig performance. From d 0 to 14,
the mean ADG and ADFI of pigs fed additional
lactose, regardless of source, was greater and tended to be greater compared to those fed no supplemental lactose. Pigs fed
edible grade whey had increased ADFI and
tended to have increased ADG as lactose
increased from 9 to 18%. When Dairylac
80 or granular whey was included in the
diet, ADG and ADFI were increased over the
control, but no further improvement above
the 9% level was observed. However, pigs
fed 9% granular whey and Dairylac 80 had
similar performance to those fed 18% edible
grade whey. For pigs fed Dairylac 80, F/G
also improved linearly as lactose increased to 18% in the diet. No differences in growth
performance were observed among lactose
sources used in this study.