A new research paper has found that many horse owners have an incomplete understanding of the factors that influence sugar levels in pasture grass, despite the well-established links between high-sugar grass and conditions such as laminitis.
The study, Scientific Evidence and Common Perceptions of Factors Affecting Sugar Content in Pasture Grass, was carried out by Isabel Moaby, Alex Aitken and Sandra Varga and published in the journal Veterinary Medicine and Science. It explored how well people responsible for horses understand the environmental and management factors that affect grass sugar content, and whether greater horse-related experience improves that knowledge.
Why grass sugar matters
High levels of non-structural carbohydrates (NSC), often referred to as “sugars”, in grass are known to be associated with, and can exacerbate, a range of equine health problems, most notably laminitis. Understanding when and why sugar levels rise in pasture is, therefore, a key part of making informed grazing and management decisions.
What the researchers did
The team developed an online questionnaire that was completed by 194 people who identified as equine owners or as being responsible for horse management. Participants were asked about their understanding of factors that affect grass sugar content, including environmental conditions and pasture management practices. The researchers also looked at whether respondents’ level of horse-related experience was linked to more accurate knowledge.
Key findings
The results showed that participants were relatively well informed about some influences on grass sugar levels, but there were notable gaps in knowledge. In particular, understanding was weaker around:
- the role of fungi in grass and how plant–fungal interactions may influence sugar content
- the impact of overgrazing and rotational stocking on NSC levels
Perhaps surprisingly, the study found that greater horse-related experience did not consistently translate into better knowledge of grass sugars, equine nutrition, or related health risks. According to the authors, this suggests that experience alone is not enough to ensure accurate understanding.
Implications for horse management
The researchers conclude that there is a clear need for improved knowledge exchange between the scientific community and those who manage horses day to day. Better dissemination of research on pasture biology, particularly the effects of fungi and grazing strategies on grass sugar content, could help owners make more informed decisions and reduce health risks for horses.
They also highlight the potential to use plant–fungal interactions as a management tool to influence grass establishment, growth, and sugar content in paddocks, an area that may warrant further research and practical guidance.
Why this matters for horse owners
For horse owners and yard managers, the findings underline that commonly held assumptions about grass and sugar levels may not always align with the science. Improving access to clear, evidence-based information on pasture management could play an important role in protecting equine health, particularly for horses and ponies at risk of laminitis.
