Safety of a feed additive consisting of Duddingtonia flagransNCIMB 30336 (BioWorma®) for all grazing animals (International Animal Health Products Pty Ltd).

Overview

• This research article evaluates the safety of the feed additive BioWorma®, containing the fungus Duddingtonia flagrans NCIMB 30336, for all grazing animals excluding dairy bovines, sheep, and goats.
• The assessment concludes that the additive is safe for various grazing animals such as pigs, rabbits, horses, deer, and alpacas when used as recommended.

Background and Context

• BioWorma® is a feed additive containing spores (chlamydospores) of the fungus Duddingtonia flagrans NCIMB 30336.
• Duddingtonia flagrans is known for its ability to trap and kill parasitic larvae in the environment, making it valuable for controlling parasites in grazing animals.
• Previously, the European regulatory body (FEEDAP Panel) assessed the additive’s safety and efficacy for dairy bovines, sheep (ovines), and goats (caprines).
• However, safety for other grazing animals like pigs, rabbits, horses, deer (Cervidae), and alpacas (Camelidae) was not concluded due to limited data.

Objectives of the Current Assessment

• To provide a scientific opinion to the European Commission on whether BioWorma® is safe for all grazing animals beyond the initially assessed species.
• The target species included:
  • Pigs (all categories)
  • Rabbits (all categories)
  • Horses (all categories)
  • Calves or kids belonging to the Cervidae and Camelidae families (e.g., deer, alpacas)

Methodology and Data Considered

• The applicant referred to a previously conducted sub-chronic oral toxicity study.
• This study evaluated the safety of the additive when ingested over an extended period but was initially used for other species.
• The FEEDAP Panel considered this study relevant because:
  • The additive is administered as chlamydospores, which are dormant fungal spores unlikely to germinate and proliferate within the gastrointestinal tract.
  • This reduces the risk of unexpected fungal growth or toxicity in the animals’ bodies during digestion.
• Based on this, results from the sub-chronic toxicity study were used to extrapolate safety for the broader group of grazing animals.

Key Findings

• Derived the No Observed Adverse Effect Level (NOAEL) from the sub-chronic oral toxicity study, which indicates the maximum dose that causes no harmful effects.
• Calculated maximum safe levels of the additive intake were higher than the expected intake from recommended usage levels across all target species.
• Thus, BioWorma® is unlikely to cause toxic effects at the recommended doses for these animals.

Conclusion

• The FEEDAP Panel concluded that BioWorma® is safe for all grazing animals including:
  • Bovines (cattle)
  • Ovines (sheep)
  • Caprines (goats)
  • Rabbits
  • Horses
  • Cervids (deer and relatives)
  • Camelids (alpacas and relatives)
  • Porcine species (pigs)
• Safety is assured under the proposed conditions of use, i.e., at the recommended dosage.

Implications

• The confirmed safety of BioWorma® for a broad range of grazing animals supports its wider adoption in animal farming.
• This may aid in integrated parasite management programs by reducing parasitic infections without adverse health effects on the animals.
• Providing a safe biological control agent can contribute to reducing reliance on chemical anthelmintics, potentially lowering resistance development in parasites.