There were 8 replications at each station for a total of 24 replications per treatment with 5 or 23 pigs per pen
As expected, ADG,ADFI, and G:F were not affected (P = 0.10) during theinitial 2-wk period when all pigs received the same diet.
During wk 3 and 4 (phase 3) when the 5 levels of lactose
were fed, ADG and ADFI increased linearly (P < 0.01)
with increasing levels of lactose, but G:F was not affected
(P = 0.10). Although the quadratic component
was not significant, ADG and ADFI reached a numerical
plateau at the 7.5% inclusion level of lactose during
phase 3. Compared with pigs fed the diet without lactose,
the 7.5% level of lactose resulted in 350 g of additional
BW gain coupled with 420 g of additional feed
consumed per pig during phase 3, and most of the additional
BW gain (294 g) was maintained through the
end of the 5- to 6-wk study. These results suggest that
pigs respond to dietary lactose during the mid to latter
phase of the nursery period and that the response was
obtained under different management and facility conditions.