4. Discussion
Clay minerals have been used as an antidiarrheal drug in pigs because
of their absorption properties (Phillips, 1999). In this study, dietary
supplementation with palygorskite decreased the rate of diarrhea,
which indicates that palygorskite was effective in protecting weaned
piglets from diarrhea. A previous study has shown that clay supplementation
decreased the colonization and shedding of E. coli by
experimental weaned pigs, and the duration of infection was shorter
(Trckova et al., 2009). In addition, the superior growth performance
shown by the palygorskite groups in this study was in agreement with
previous results, which demonstrated that dietary supplementation
with palygorskite could improve growth performance as a result of the
absorption of adverse factors in the feed and a reduction in intestinal
impairment in weaned piglets (Guangmin et al., 1992). Also, it has
been reported that the adhesion of palygorskite to heavy metals could
inhibit the growth of bacteria (Lavie and Stotzky, 1986). Therefore, the
improvement of growth performance shown by the palygorskite groups
in this study can be attributed to the protective effect of palygorskite
against diarrheal infection.