We always through that the r-epimer was more active than the s-epimer, so more toxic than the s and there's some evidence that with processing the s-epimer is becoming more and the r-epimer is becoming less, so we hypothesised that processing with pelleting, steam explosion, extrusion would decrease the overall toxicity of the ergot alkaloids by changing the epimer ratios.
So, we conducted feeding trials with pigs at the Prairie Swine center and we fed them diets with zero to four parts per million ergot alkaloids with or without processing.
We did indeed see effects of ergot but we saw no effect of processing on these results.Whether the feed had been processed by extrusion or pelleted, it did not effect the toxicity.4 ppm ergot had the same effect regardless of processing.
Dr. Beaulieu says, since the epimer profile was changed with processing but we saw no effect on toxicity, researchers have concluded that the r-epimer and s-epimer have equal toxicity.
Source : Farmscape.ca