Epsilon Archive for Student Projects

Abstract

Ataxia, tremors and even death are the possible consequences for both horses and cattle when their feed contains endophyte-derived toxins from Epichloë spp. In Sweden and elsewhere, the dangers of the toxins lolitrem B and ergovalin derived from Epichloë spp. are not fully understood. In pregnant mares, toxin-contaminated feed can cause hormonal imbalances affecting progesterone, prolactin, and relaxin, which can be a serious health risk for the animal since these hormones are critical for healthy foaling. Besides the animal perspective, Epichloë spp. can also be of major concern in seed crop production, as the visible symptoms of fungal stromata inhibit host inflorescence, ultimately resulting in seed yield losses of 9-100%.
In order to increase the knowledge about Epichloë spp. in Sweden, molecular diagnostics and consultations with the agricultural sector were carried out. By isolation and molecular diagnosis using ITS primers, one Epichloë sp. was identified from a total of 82 isolates. The cultivated isolates originated from known hosts of Epichloë spp. such as timothy, meadow fescue and cocksfoot. The sampling sites were located in the counties of Uppland and Västmanland. Apart from one Epichloë sp., 25 fungal isolates remain as no hits, unclassified or uncultivated fungi when performing BLASTn, leaving completely new species to be investigated for future work. In addition, several genera of fungi commonly found in cereals were observed. These included Alternaria, Epiccocum, Cladosporium, Parastagonospora, Fusarium, Colletothricum, Phaeosphaeria and Microdochium.
During consultations with experts within the sector, it became clear that in Sweden there is currently no possibility to test for possible harmful endophyte-derived toxins from Epichloë-infected forages, leaving animal owners uncertain whether the problems would increase in the future. In order to fill the current knowledge gaps and to gain a better understanding of the problems associated with Epichloë spp. in Sweden strong collaborations within animal husbandry, plant pathology and toxicology are needed. The overall understanding of the epidemiology, presence and life cycle of Epichloë spp. in forage grasses remain low in Sweden despite the significant amount of ley grown.