[Nutrient content and adequacy of roughage for horse nutrition: an investigation under Swiss conditions].

This research analyzes the nutritional and macromineral content in hay, straw, silage/haylage, and green forage used in horse feed in Switzerland, noting that there are no existing nutrient tables for these specifically for horses. The quality of the samples was generally adequate for equine consumption, though the mean contents of crude protein, calcium, magnesium, and phosphorus were lower compared to what is found in tables for ruminants. The dry matter content and fructan levels also varied widely across samples, opening further discussions for more specific resource tables.

Investigating Roughage Nutritional Content

• This research involved collecting samples of hay, straw, silage/haylage, and green forage from 46 horse-keeping farms across 22 cantons in Switzerland. This wide-ranging collection was designed to ensure an extensive sample set that possibly covers varying farming practices and environmental conditions which could affect the nutritional content of the roughages.
• The samples underwent evaluation based on sensory characteristics and were analyzed for nutrient and macromineral (calcium, magnesium, phosphorus) content, fructan levels, and quality. No sample was found to be entirely subpar for horse consumption, indicating that, generally, the roughages fed to horses in Switzerland are of decent quality.

Quality Compared to Ruminant and German Horse Hay

• When comparing the Swiss hay samples against hay for ruminants and German hay for horses, there was a consistent deficiency of crude protein in the Swiss samples. This suggests a potential issue with protein intake for horses in Switzerland consuming only locally-produced hay and could necessitate a revision in feeding patterns or diet supplements.
• The mineral content in sampled roughages, including calcium, magnesium, and phosphorus, were also found to be lower on average than the values indicated in ruminant feed tables. The researchers didn’t indicate any severe deficiencies, but this might pave the way for further research into the mineral content and its impact on equine health.

High Dry Matter Content and Fructan Levels

• The haylage/silage samples had a higher dry matter content of more than 40%, with all but one sample. This percentage is higher than the standard in the scientific literature. The researchers suggest that there is a gap in current research as they couldn’t find any nutrient tables for silage or haylage with such high dry matter content.
• The fructan levels also varied widely across samples, with the maximum recorded fructan level of approximately 94 g/kg dry matter. Considering the crucial role fructans play in horse digestion and health, especially in preventing laminitis, this study’s findings indicate a need for more detailed nutrient tables that take these factors into account.