Effects Of Fusarium Toxins On Injuries Of Liver And Spleen In Weaned Gilts

The objective of the study was to systematically investigate the effects of Fusarium toxins on injuries of liver and spleen in weaned gilts, as well as the natural recovery after stopping supply of the Fusarium toxins. The study was based on the determination of serum liver function indices and antioxidant indices, expressions of inflammatory cytokines, histological observations of liver and spleen.To investigate the effects of Fusarium toxins on injuries of liver and spleen in weaned gilts, total of 50 weaned gilts(Duroc × Landrace × Yorkshire) aged at 35 d with body weight of 8.45 ± 0.94(mean ± SD) kg were randomly allocated into 2 groups with 20 in Control group and 30 in Fusarium toxins group, and one gilt was a replicate. Gilts in Control group were fed a basal diet, and gilts in Fusarium toxins group were fed a Fusarium toxins-contaminated diet(0.90 mg/kg ZEN, 1.43 mg/kg DON, 5.85 mg/kg FUM) made by replacing 50% of corn and corn gluten meal in the basal diet with moldy corn and moldy corn gluten meal. The trial lasted for 35 d after 7 d adaptation. At the end of the experiment, 10 gilts per group were slaughtered and sampled. The main results showed that, 1) Compared with Control group, Fusarium toxins significantly increased serum enzyme activities and decreased liver protein synthesis ability and antioxidant capacity(P<0.05), and the changes of serum antioxidant indices were in accordance with those of liver. Relative weights of liver were significantly decreased, and expressions of inflammatory cytokines IL-1β and IL-6 were significantly increased(P<0.05) with a different distribution. Histological examination of liver in Fusarium toxins group revealed a certain degree of damage, with obvious inflammatory cell infiltration partly at the margin of hepatic lobule and vacuoles degeneration of local hepatic cells. 2) Fusarium toxins significantly reduced spleen antioxidant capacity(P<0.05) in accordance with the changes of serum and liver. Compared with Control group, there were no significant changes in relative weights of spleen(P>0.05), and expressions of inflammatory cytokines IL-1β and IL-6 were significantly increased(P<0.05) in Fusarium toxins group with a different distribution. Histological examination of spleen in Fusarium toxins group revealed a certain degree of damage, with white pulp area decreased significantly, red pulp area expanded and vacuoles degeneration of local splenic cells.To investigate the natural recovery to liver and spleen injury of weaned gilts after stopping supply of Fusarium toxins-contaminated diet, 10 gilts were randomly selected from Fusarium toxins group in the previous trial for Natural recovery group, in which the Fusarium toxins-contaminated diet was changed by the basal diet. And the rest of the gilts is still in the original group with one gilt per replicate. This trial lasted for. All gilts were slaughtered and sampled after 21 d feeding. Results showed that after stopping supply of Fusarium toxins-contaminated diet, serum enzymes activities were significantly decreased, and liver protein synthesis ability were significantly improved(P<0.05) compared to Fusarium toxins group, but they were still significantly different from the Control group(P<0.05). The antioxidant capacity of liver and spleen were improved to some extent, and was consistent with changes of serum antioxidant indices. Expressions of inflammatory cytokines IL-1β and IL-6 were significantly decreased in Fusarium toxins group(P<0.05), with no significant differences with Control group(P>0.05).These results indicated that Fusarium toxins(0.90 mg/kg ZEN, 1.43 mg/kg DON, 5.85 mg/kg FUM) could induce changes of serum liver function indices, impair the antioxidant ability of liver and spleen, cause the abnormal gene expression of inflammatory cytokines, and thus result in liver and spleen injuries. After stopping supply of Fusarium toxins-contaminated diet, the injuries to liver and spleen of weaned gilts could recover to some extent, but could not return to normal levels yet.