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Home / Equine Research Bank / Front Pharmacol / Edaphic and Phytochemical Factors as Predictors of Equine Gr...
Frontiers in pharmacology2010; 1; 122; doi: 10.3389/fphar.2010.00122

Edaphic and Phytochemical Factors as Predictors of Equine Grass Sickness Cases in the UK.

Abstract: Equine dysautonomia or equine grass sickness (EGS), as it is more commonly known, is a usually fatal disease of equids of uncertain etiology, although associated with grazing, that affects the autonomic and enteric nervous system. Lowered gastrointestinal motility, leading to paralysis of the gut, is one of the main symptoms of EGS. Previous studies have implicated anaerobic bacteria, notably Clostridium botulinum, but what triggers the severe bacterial infestations remains enigmatic. We hypothesized that a detailed comparison of soil mineral and botanical composition of EGS and control sites would yield new insights into the causation of the disease. Results: Between March 2007 and September 2008, soil, plant, and water samples from a total of 23 EGS sites and 11 control sites were studied. Metal and non-metal element levels of the soil and herbage samples were assessed. Significantly, EGS sites had higher levels of soil nitrogen, and significantly higher levels of iron, lead, arsenic, and chromium in the herbage. Toxic Ranunculus spp. (buttercups) were found in abundance at every EGS site, making ingestion plausible. Conversely, neurotoxin-producing cyanobacteria were not found in any of the water samples analyzed. Conclusions: The significantly higher levels of iron and heavy metals found in herbage growing in EGS sites, in addition to toxic Ranunculus species, suggest that previously unknown triggers are involved in a multi-factorial EGS etiology. Our results also show that cyanobacteria on the other hand, are unlikely to be a factor in EGS. Consequently, the concomitant presence of two (or more) factors could be the trigger for an outbreak of EGS.
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Publication Date: 2010-10-25 PubMed ID: 21833167PubMed Central: PMC3153002DOI: 10.3389/fphar.2010.00122Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research study investigates the relationship between soil minerals, the chemical compounds of plants, and Equine Grass Sickness (EGS), a grave disease affecting horses. Through comparing EGS impacted areas with uncontaminated locations, the study discovers that higher levels of specific heavy metals in plants and certain poisonous plant types could have a role in causing EGS.

Research Methodology

  • The study was conducted between March 2007 and September 2008, with soil, plant, and water samples collected from 23 EGS sites and 11 control sites.
  • The collected samples were studied for the presence and levels of multiple elements, both metal and non-metal.

Key Findings

  • Significantly, EGS sites had elevated levels of soil nitrogen and higher levels of iron, lead, arsenic, and chromium in plants on the site.
  • Ranunculus species, or buttercups, that are known to be toxic were found abundantly at each EGS site, implying that animals grazing at these sites could easily ingest them.
  • Conversely, no neurotoxin-producing cyanobacteria were found in any of the water samples taken from either EGS or control sites, thus dismissing the possibility of their role in causing EGS.

Conclusions

  • The results of the study point to the fact that higher levels of certain heavy metals in plants coupled with the presence of toxic Ranunculus species could serve as triggers for EGS, thus suggesting a complex multi-factorial cause for the disease.
  • The absence of cyanobacteria in all water samples suggests that they are unlikely to be a factor contributing to the onset of EGS.
  • It is proposed that the presence of two or more factors might be needed to trigger an episode of EGS, indicating that individual factors in isolation may not be sufficiently causative.

Cite This Article

APA
Edwards SE, Martz KE, Rogge A, Heinrich M. (2010). Edaphic and Phytochemical Factors as Predictors of Equine Grass Sickness Cases in the UK. Front Pharmacol, 1, 122. https://doi.org/10.3389/fphar.2010.00122

Publication

Frontiers in pharmacology
ISSN: 1663-9812
NlmUniqueID: 101548923
Country: Switzerland
Language: English
Volume: 1
Pages: 122

Researcher Affiliations

Edwards, Sarah E
  • Centre for Pharmacognosy and Phytotherapy, The School of Pharmacy, University of London London, UK.
Martz, Kathrin E
    Rogge, Anja
      Heinrich, Michael

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        Citations

        This article has been cited 2 times.
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