Lactational passage of fusaric acid from the feed of nursing dams to the neonate rat and effects on pineal neurochemistry in the F1 and F2 generations at weaning.

Fusaric acid is produced by several species of Fusarium and is found in corn, corn-based foods and feeds, wheat, barley, and other cereal grains. Given parenterally to rats, the mycotoxin affects neurochemical parameters in the pineal gland associated with growth and maturation. Since little information exists concerning the dietary effects of fusaric acid, the mycotoxin was mixed with feed at 10, 75, and 200 ppm and fed ad libitum to pregnant rats (F0 dams) from d 11-12 of gestation, through parturition and weaning (F1 generation). On d 4 postpartum, F1 pups were culled to 9-10 pups/litter; the stomach colostrum was collected from the culls and analyzed for fusaric acid. The mycotoxin in the colostrum (ng fusaric acid/100 mg colostrum) was directly related to the amount consumed by the nursing dams (i.e., 200 ppm pups, 3547 ng; 75 ppm pups, 1449 ng; 10 ppm pups, 80 ng; controls pups, 18 ng). All other animals survived, and appeared normal, healthy, and in good pelage. F0 dam feed consumption and dam and pup weights were not statistically different, but there was an inverse relation between pup average weight gain and amount of fusaric acid in the diets (i.e., weight gains: control pup > 10 ppm pup > 75 ppm pups > 200 ppm pups). At weaning, the F1 pups were randomly assigned to two groups per treatment: one group (F1A) for reproduction and fusaric acid effects on the F2 generation, and another group (F1B) for neurochemical comparisons. The F1A rats were maintained on their respective diets to age 13-14 wk; animals were bred (i.e., control males x control females, 10 ppm x 10 ppm, etc.) and the F1A dams and F2 pups were monitored as already described. Weight gains and fusaric acid in stomach colostrum from the F2-culls were analogous to the F1 generation. On d 5-6 and 7-8 postpartum, using litter weight gains as an indication of milk production in the F1A dams (controls vs. 200 ppm), the controls gained 32.5% (p < .01) and 13.3% (p < .02), respectively, more than 200 ppm F2 pups. At weaning, no differences were observed in neurochemicals in the pineal gland for the F1 generation. However, in the F2 200 ppm male and female weanlings, fusaric acid decreased pineal serotonin (males, p < or = .001; females, p < or = .15) and tyrosine (males, p < or = .04; females, p < or = .07). The results indicate fusaric acid in diets at < or = 0.3 ppm (i.e., background control diet) lactationally passes from nursing dams to the neonate; in weanlings, at 200 ppm, fusaric acid decreases pineal serotonin and tyrosine. The data also suggest limited neonate weight gains may be related to either decreased milk production in dams or mycotoxin effects on the neonate. This is the first report of fusaric acid's lactational passage from the feed of nursing dams to neonates and the oral suppression of pineal serotonin and tyrosine in offspring.

Immunosuppressive effects of Fusarium moniliforme corn cultures in chickens.

In the present study, the toxic and immunosuppressive effects of three isolates of Fusarium moniliforme (MRC 826, MRC 1069, and RRC 408) in male White Leghorn chickens were investigated. Chickens were fed diets containing .5, 5.0, or 25% of F. moniliforme corn cultures for 6 wk. About 30% of the chickens fed RRC 408 had leg weakness. Relative weights of bursae of Fabricius were lower in birds fed all doses of MRC 826. Birds fed 5.0 or 25% MRC 1069 had lower relative spleen weights. Thymus weights were lower in birds fed .5 and 5.0% RRC 408, but not in those fed 25%. Immunosuppressive effects were determined by measuring serum levels of primary and secondary agglutinin responses to SRBC and Brucella abortus. Birds fed 5.0 or 25% MRC 826 were immunosuppressed, as shown by low antibody titers to B. abortus in both the primary and secondary responses. Isolate MRC 1069 caused a decrease in secondary response to SRBC at 25% and B. abortus at the 5.0 and 25% of culture material. The RRC 408 isolated reduced the secondary response to SRBC at all doses and response to B. abortus at 5.0 and 25% of culture material. These results appear to be the first report that feed contaminated with F. moniliforme can produce deficiencies in the immune system of chickens.