Aspergillus fumigatus toxicity and gliotoxin levels in feedstuff for domestic animals and pets in Argentina.

The study investigates levels of the toxic substance gliotoxin produced by the Aspergillus fumigatus fungus in different animal feeds (for pigs, poultry, cattle, horses and pets). It found fungi present in all tested samples, with the highest levels of gliotoxin found in horse and poultry feeds. The presence of gliotoxin can pose a risk to both the health of the animals consuming the feed and the workers handling it.

Research Objective and Methodology

• The study aimed to evaluate the production of a potent mycotoxin, gliotoxin, by Aspergillus fumigatus strains isolated from various animal feedstuff. It also sought to determine the amount of gliotoxin present in these feedstocks.
• A total of 150 feedstuff samples were collected. These were composed of 30 samples each from five different categories of feed – for pigs, poultry, cattle, horses, and pets.
• The presence of Aspergillus fumigatus and its capacity to produce gliotoxin was determined using high-performance liquid chromatography (HPLC), a technique used for separating and identifying compounds in a sample.

Key Findings

• Aspergillus fumigatus strains were isolated from all tested samples, indicating a widespread presence of the fungus in animal feed supplies.
• Strains from cattle, horses, and pet food demonstrated the ability to produce gliotoxin.
• The corn silage samples meant for cattle were found to be free of gliotoxin contamination. However, all other tested samples displayed varying levels of gliotoxin from 29 to 209 micrograms per gram.
• Horse and poultry feed samples were the most contaminated with this mycotoxin.

Implications and Conclusions

• Feed contaminated with gliotoxin can be potentially harmful to animals, affecting their productivity and overall health.
• Human health risks also exist, specifically for farm workers who might be exposed to contaminated animal feed during handling.
• The study suggests that strategies to prevent and control Aspergillus fumigatus contamination should be devised, taking into consideration the source of the feed samples.