Mycotoxicological investigations on maize and groundnuts from the endemic area of Mseleni joint disease in Kwazulu

Abstract

Samples of home-grown maize and groundnuts from the endemic area of Mseleni joint disease (MJD) during four seasons (1980-1983) were examined mycologically. The mycoflora of these dietary staples included Fusarium poae and F. oxysporum, which have been implicated in the aetiology of Kashin-Beck or Urov disease, another osteo-arthrosis endemic in Siberia and China. Two other species of Fusarium, i.e. F. moniliforme and F. equiseti, implicated in syndromes of abnormal bone development in animals, were also present. The predominant fungus associated with maize kernels was F. moniliforme; two other fungi relatively frequently isolated from Mseleni maize, i.e. F. compactum and Lasiodiplodia theobromae, have not previously been reported in maize in southern Africa. The predominant fungi associated with groundnut kernels were Penicillium spp., L. theobromae, Macrophomina phaseolina and F. oxysporum. The incidence of certain fungi, particularly F. compactum, F. oxysporum and L. theobromae, appeared to be higher in dietary staples from households affected by MJD than from non-affected ones. The numbers of samples examined were, however, small and these findings need to be confirmed. Cultures of 120/322 isolates of fungi from Mseleni dietary staples proved toxic to ducklings, the most toxic species being F. compactum, F. moniliforme, F. oxysporum and Phomopsis sp. The characteristic pathological changes of MJD have, however, not been induced in experimental animals with cultures of any of these fungi. A diet containing maize and groundnuts from households affected by MJD also failed to induce the characteristic osteo-arthritic changes of MJD in rats. The dietary staples used in this experiment were, however, collected during seasons of abnormally low rainfall at Mseleni.(ABSTRACT TRUNCATED AT 250 WORDS)