Evaluation of haylage vs. hay for horse feeding with regard to microbiological feed quality, mites, mycotoxins and fructans

Created: February 25, 2026
Last updated: February 27, 2026

Ing. Reinhard Resch

Head of Department Analytics and Feed Evaluation

High-fiber hay with a moisture content exceeding 14% often leads to microbial spoilage in the hayloft and mold growth, which can cause health problems in horses. Studies show that haylage (fermented hay) is a good alternative for horses with respiratory problems; however, horse owners often have reservations about it (due to concerns about the smell of fermented feed, etc.).

The aim is to compare haylage bales produced under practical conditions with ground hay or ventilated hay in precise experiments conducted at horse hay producers (Piber Federal Stud, Federal Experimental Farms). Hygiene parameters such as yeast, molds and mites, fructan content and mycotoxins, as well as nutrients, structural components and energy are examined.

The cooperation project has a second DaFNE project component (No. 102229) which is led by Dr. Sonja Axmann (AGES Linz).

Project duration: March 2026 to April 2028

Horses eating haylage