Detection of Fungal Occurrence and Mycotoxin Contamination in Grasses Hay

Abstract

Forage grasses are a vital nutritional source for ruminants. Roughage is the primary energy source for ruminants. However, stored forage is frequently susceptible to fungal contamination. Such contamination usually occurs in two main ways: either through direct fungal growth on the forage or via the transfer of mycotoxins from contaminated feed consumed by ruminants. This study investigated fungal contamination and mycotoxin levels in three grass hay samples: two from mauritius grass and one pangola grass. Fungal isolation was performed using the dilution plate method on four different types of culture media. The results indicated that czapek-dox agar and rose bengal agar were more effective for fungal enumeration compared to czapek-dox agar supplemented with dicloran or malachite green. Fusarium spp. was detected in all forage grass hay at concentrations ranging from 3.0 – 6.0 × 104 CFU/g, while Penicillium spp. was found at 1.1 – 5.9 × 104 CFU/g, except the pangola grass hay sample showing the lowest Penicillium spp. count 0.2 – 0.6 × 104 CFU/g. Mycotoxin analysis using the ELISA method revealed that concentrations of deoxynivalenol, T-2/HT-2 toxins, and fumonisin were within the European Union regulatory limits. However, the zearalenone level in the pangola grass hay sample was found to be 517 ppb., exceeding the 500 ppb. safety threshold. These toxins are predominantly reported to originate from Fusarium spp. This study highlights the potential for mycotoxin accumulation in forage and emphasizes the importance for farmers to implement proper storage practices and mycotoxin control measures to ensure animal safety.