Fumonisin B1 Accumulates in Chicken Tissues over Time and This Accumulation Was Reduced by Feeding Algo-Clay

Abstract

The toxicokinetics of the food and feed contaminant Fumonisin B (FB) are characterized by low oral absorption and rapid plasma elimination. For these reasons, FB is not considered to accumulate in animals. However, recent studies in chicken and turkey showed that, in these species, the hepatic half-elimination time of fumonisin B1 (FB1) was several days, suggesting that FB1 may accumulate in the body. For the present study, 21-day-old chickens received a non-toxic dose of around 20 mg FB1 + FB2/kg of feed to investigate whether FB can accumulate in the body over time. Measurements taken after four and nine days of exposure revealed increased concentrations of sphinganine (Sa) and sphingosine (So) over time in the liver, but no sign of toxicity and no effect on performances were observed at this level of FB in feed. Measurements of FB in tissues showed that FB1 accumulated in chicken livers from four to nine days, with concentrations of 20.3 and 32.1 ng FB1/g observed, respectively, at these two exposure periods. Fumonisin B2 (FB2) also accumulated in the liver, from 0.79 ng/g at four days to 1.38 ng/g at nine days. Although the concentrations of FB found in the muscles was very low, an accumulation of FB1 over time was observed in this tissue, with concentrations of 0.036 and 0.072 ng FB1/g being measured after four and nine days of exposure, respectively. Feeding algo-clay to the chickens reduced the accumulation of FB1 in the liver and muscle by , approximately 40 and 50% on day nine, respectively. By contrast, only a weak non-significant effect was observed on day four. The decrease in the concentration of FB observed in tissues of chickens fed FB plus algo-clay on day nine was accompanied by a decrease in Sa and So contents in the liver compared to the levels of Sa and So measured in chickens fed FB alone. FB1 in the liver and Sa or So contents were correlated in liver tissue, confirming that both FB1 and Sa are suitable biomarkers of FB exposure in chickens. Further studies are necessary to determine whether FB can accumulate at higher levels in chicken tissues with an increase in the time of exposure and in the age of the animals.

Strong Alterations in the Sphingolipid Profile of Chickens Fed a Dose of Fumonisins Considered Safe

“…This observation is in agreement with studies in mammals [8]. This is of particular interest because the effects were observed at a nontoxic dose of FB in feed [1,23]. The sphingoid bases are membrane-permeable, but changes in Sa and So were not observed in plasma in the present study, confirming that effects of FB on the liver are easier to characterize [16,24,32].…”

“…The effects of FB on sphingolipids in plasma are reported in Table 4. No effect of FB on Sa and So was observed in this study, in agreement with the literature data on this level of FB in feed [23,25]. Interestingly, a significant increase in Sa1P (d18:0P) occurred, while a weak, nonsignificant increase in So1P (d18:1P) was also observed.…”

“…Because d18:0 is known to be the best biomarker of an effect of FB, the high recovery observed for d18:0 could be problematic when detecting an effect of FB in chickens. Consequently, the methods were compared to reveal whether similar results would be obtained with the method developed in this study and an older method in which d18:0 contents were measured by fluorescence detection after derivatization with orthophtalaldehyde [23]. As shown in Figure 2A, Passing and Bablok regression revealed a very strong linear correlation between the two methods (R² = 0.9841).…”

“…As most of these RSD were close to 20% and below 30%, they were considered as acceptable to reveal effects of FB on sphingolipids in chickens. Indeed, a strong effect of FB on sphingolipids was expected because a two-fold increase or more in SB content is generally reported at the level of 20 mg FB1+ FB2/kg feed used in this assay [23].…”

“…For the investigation, a highly sensitive method of quantification of 82 sphingolipids based on the optimized separation of the analytes by UHPLC-MS/MS was first developed. Next, the consequences of feeding FB for the sphingolipid profile were investigated in the liver of chickens in which an alteration in the Sa and So contents measured by HPLC with fluorescence detection had already been observed [23]. The method was also used in plasma to see whether alterations in the sphingolipid profile could be observed in the absence of an effect of FB on the Sa:So ratio, which is commonly used to characterize exposure to these mycotoxins.…”