EFFECTS OF FEEDING FUMONISIN B-1 IN LACTATING AND THEIR SUCKLING PIGS

The mycotoxin fumonisin B-1 (FB1) produced by Fusarium moniliforme in corn causes pulmonary edema in finishing swine. Effects of lower nonle thal amounts and effects in lactating sows with suckling pigs are unkn own. An initial study was conducted to determine a nonlethal concentra tion of FB1 for lactating sows; whether ingested FB1 could be detected in the milk; and whether toxicosis could be detected in the pigs, as determined by necropsy. Another study was conducted to determine toxic osis in the pigs by measuring liver sphinganine-to-sphingosine ratio, and whether ingested FB1 affected T-lymphocyte function in sows and th eir pigs. Furthermore, sows of this study were maintained in controlle d hot (27 to 32 C, 50 to 70% relative humidity) and thermoneutral (21 C, 55% relative humidity) environments to determine whether high tempe rature exacerbated the effects of FB1. In the first study, 100 mu g of FB1/g of corn soybean meal diet was found to be nonlethal when fed fo r 14 days. Fumonisin B-1 was not detected in the milk at 30 ppb and le sions were not found in the necropsied pigs, including 1 from a sow th at died of porcine pulmonary edema syndrome after ingesting FB1 at a c oncentration of 175 ppm. In the second study, differences in liver sph inganine-to-sphingosine ratio of pigs were not found. Expressions of c ell surface antigens on blood lymphocytes and lymphocyte proliferation response to various mitogens were not affected by FB1 or high tempera ture in sows or their pigs. The results indicated that when sows inges ted nonlethal concentrations of FB1 for 17 days, there were no detecta ble amounts of FBI in the sows' milk and no evidence of toxicosis in t heir pigs; no significant effect of FB1 on T-lymphocyte function in so ws and pigs; and no enhanced toxic effects of FB1 attributable to high temperatures.