Quantifying milk yield-dependent aflatoxin B1-to-M1 transfer in dairy cows: a Bayesian consensus toxicokinetic model

Area of Science:

• Toxicology
• Food Safety
• Animal Science

Background:

• Aflatoxin B1 (AFB1) is a hepatocarcinogenic mycotoxin found in animal feed.
• AFB1 metabolizes to aflatoxin M1 (AFM1) in dairy cow milk, posing a food safety risk.
• Previous models for AFB1 transfer to milk lacked dynamic predictions and uncertainty quantification.

Purpose of the Study:

• To develop a robust toxicokinetic model for predicting AFB1 transfer into dairy cow milk.
• To quantify the influence of milk yield on AFB1 transfer rates and associated uncertainties.
• To provide a tool for improved risk assessment and management of AFM1 in milk.

Main Methods:

• Synthesized data from 19 controlled dairy cow feeding studies.
• Employed a hierarchical Bayesian approach with a reparametrized two-compartment toxicokinetic model.
• Overcame parameter correlations and captured between-study heterogeneity to quantify prediction uncertainty.

Main Results:

• Predicted median transfer rates of AFM1 increase with milk yield, from 0.41% at 5 L/d to 3.05% at 50 L/d.
• Quantified prediction uncertainty using milk yield-dependent credible intervals (CI).
• The model successfully integrated diverse transfer data and accounted for study heterogeneity.

Conclusions:

• The developed Bayesian model accurately predicts AFM1 transfer into milk, considering milk yield and uncertainty.
• This model is valuable for quantitative risk assessment and management strategies concerning AFM1 contamination.
• Understanding transfer dynamics is essential for ensuring the safety of milk and dairy products.