AN OUTBREAK OF EQUINE LEUKOENCEPHALOMALACIA AT OAXACA, MEXICO, ASSOCIATED WITH FUMONISIN B1

Equine leukoencephalomalacia (ELEM), swine pulmonary oedema and human oesophageal cancer have been associated with fumonisine B1 (FB1) inges tion. For the first rime in this study it is reported that FB1 was ide ntified as being associated with an outbreak of ELEM at Oaxaca, Mexico . Symptoms of ELEM and Equine Venezuelan Encephalitis (EVE) are simila r and a different diagnosis is obligatory. In the geographical area (O axaca, Mexico) where donkeys died showing a neurological syndrome, 14 corn samples were collected. With the use of TLC (Thin layer chromatog raphy) and HPLC (High performance liquid chromatography) all collected samples resulted positive to FB1. In the area of study, this syndrome was reported to be the cause of death of 100 donkeys, after 3 postmor tem examinations in which macroscopic and microscopic cerebral white m atter liquefactive necrosis were observed, when FB1 concentration was determined in the samples collected, using HPLC and TLC. It was conclu ded that HPLC is a highly sensitive method for the detection of FB1 th rough the formation of an OPA derivative. However, the reverse phase T LC plate nad the visualisation of the coloured reaction with the vanil lin acidic solution is more objective. FB1 concentration in the studie d samples ranged from 0.67 to 13.3 ppm. It was concluded that FB1 was the causae of leukoencephalomalacia reported in donkeys in the slate o f Oaxaca, Mexico.