Influence of dietary nivalenol exposure on gross pathology and selected immunological parameters in young pigs

Abstract

Young pigs were fed diets to which 0, 2.5, or 5 mg/kg of purified nivalenol (NIV) had been added. The exposure continued for 3 weeks without any signs of feed refusal, vomiting, or change in clinical appearance, and there were no changes in body or organ weights due to the exposure. However, the concluding macroscopic examination revealed gastrointestinal erosions and signs of nephropathy in most of the exposed pigs. There were no differences in total or differential blood leukocyte counts between control and exposed pigs in blood samples collected after 0, 1, or 3 weeks, nor in the number of thymocytes at the end of the trial. Spleen cell numbers showed a dose‐dependent decrease after 3 weeks of exposure that was statistically different from controls in pigs exposed to 5 mg NIV/kg. Flow cytometric analysis of lymphocytes revealed decreased numbers of both the CD4+ and the CD8+ subpopulations in the spleen at this point in time, reflecting the lower numbers of splenocytes; but no proportional changes were seen. In blood, exposure to NIV caused a transient decrease in the proportion of CD4+ cells after 1 week of exposure. Analysis of IgG and IgA in plasma showed a time‐dependent tendency of increasing plasma concentrations of IgA and decreasing concentrations of IgG in the 2.5 mg/kg group, but differences in Ig levels between experimental groups and controls were not observed at any time. No differences were seen in the mitogen‐induced proliferation by lymphocytes from blood, spleen, or thymus. In conclusion, exposure of young pigs to NIV in the diet caused pathological alterations in the kidneys and gastrointestinal tract and reduced the number of splenocytes. The results also indicated that exposure to NIV caused a time‐dependent increase in IgA production in the 2.5 mg/kg group. Nat. Toxins 5:238–246, 1997. © 1998 Wiley‐Liss, Inc.

Meta-analytical study of productive and nutritional interactions of mycotoxins in growing pigs

“…Some substances, such as alimentary toxins, can also act as limiting factors in the diet selection, as animals may relate the consumption of contaminated feed with discomfort sensations (Hedman et al, 1997;Forbes, 2007). In naturally contaminated diets, a reduced consumption can also be related to organoleptic changes caused by fungal contaminants (Akande et al, 2006).…”

Meta-analysis of individual and combined effects of mycotoxins on growing pigs

“…Some theories assert that alimentary toxins may act as limiting factors in diet selection, because animals relate their consumption to the metabolic consequences of discomfort or specific clinical signs (Hedman et al, 1997). Diets produced with naturally-contaminated grains may also be refused by the animals due to the organoleptic changes caused by fungal contaminants (Akande et al, 2006).…”

Effect of subacute oral doses of nivalenol on immune and metabolic defence systems in mice

“…The simultaneous changes in plasma urea levels and alkaline phosphatase activity reflect a hepatotoxicity in mice receiving the highest dose of NIV. Due to the well-established isotypespecific dysregulation of immunoglobulin production in pigs exposed to NIV [8], the effects of various doses of this toxin were compared on plasma immunoglobulin profiles of mice. NIV treatments did not alter the plasma levels of both IgA and IgM, independently of the dose.…”

“…When administered in short-term assays, at doses higher than 6 ppm in animal feeds, NIV has been described to cause feed refusal, decrease in weight gain, increase in serum alkaline phosphatase activity and elevation of serum IgA level and mesangial IgA deposits in mice [9,22]. Doses of 2.5 or 5 mg/kg of pure NIV added to the diet of young pigs, caused pathological alterations in the kidneys and gastrointestinal tract and reduced the number of splenocytes [8]. The results also indicated that exposure to NIV causes a time-dependent increase in IgA production in the 2.5 mg/kg group.…”