The scores of footpad and hock burns were increased
by stocking density and increased with age (Table 5).
This result is in line with previous works of Dozier et al.
(2005), who reported that stocking density increased
the footpad burn score and the response was more pronounced
if stocking density increased to 40 and 45 kg
of BW m-2 of floor space. It is reported that there is a
correlation between footpad burn and litter quality
(Haslam et al. 2006, 2007). The increase in footpad
lesion scores is probably a reflection of the poor litter
quality associated with high stocking density (Dozier
et al. 2006).
Litter moisture is suggested to be associated with
the incidence of footpad burn (Imaeda 2000). In line
with the previous result of Do et al. (2005), alum treatment
had no significant influence on litter moisture during
the whole experimental period (49 d), though the litter
moisture tended to be increase in the period of the 1st 3
wk of age. In contrast, litter moisture was increased
with stocking density, which was believed to be related
to the increased amount of excreta. The result suggests
that litter moisture is responsible, at least partially,
for the development of footpad and hock lesions. Alum
treatment had no significant influence on footpad and
hock burns, indicating that alum-treated litter had no
negative effect on incidence of footpad and hock lesions.
Furthermore, alum treatment resulted in decreased litter
pH (Table 3), suggesting that litter pH has no unfavorable
effect on development of footpad and hock