Economic assessment of FEC-based targeted selective drenching in horses.

The research focuses on evaluating the economic viability of Faecal Egg Counts (FEC) based targeted selective treatments (TST) to combat drug-resistant cyathostomin populations in horses, as a reasonable alternative to current treatment strategies. It explores the efficacy of individual and pooled FEC strategies and determines their maximum cost effectivity, within the financially tight horse industry. The four-year study data also indicates potential cost-savings with the use of FEC-based treatment approaches.

Understanding the Methodology

• The study involved a Welsh pony herd and the FECs were determined three times a year from 2010 to 2014.
• The study database was used to estimate the impact of FEC price, sampling strategy, either individual or pooled, and the expense of labor.
• The estimation of the costs associated with each strategy was largely inferred from simulating (via an in silico bootstrap approach) 1000 virtual pony herds based on the collected database.
• During these estimations, minimal anthelmintic costs were assumed.
• Apart from individual FEC costs, the study also investigated benefits and costs of a pooled FEC strategy – where the decision to treat is based on the group FEC values. This approach could potentially lower FEC-based costs.

Finding the Maximum Cost-Efficient FEC Price

• The simulations helped determine that an individually-based FEC strategy would not be cost-effective if the FEC price was above €5.
• Comparatively, a pooled strategy could have a lower cost impact but may result in highly infected individuals being left undrenched due to a high rate of FEC overdispersion. This creates false negatives and can affect the overall success of the treatment.
• Findings indicated that the proportion of false-negatives never exceeded 15% of the pool size with the pooled FEC strategy.
• It was found that a pool of 14 ponies and an egg count cut-off value of 150 eggs/g led to minimized costs while maintaining a reasonable level of false negatives.

Reliability of the Pooled FEC Strategy

• Real data suggested that the pool size should ideally not exceed 10 individuals as larger pools possibly reduced the correlation between average pooled FECs and the mean individual FECs due to inhomogeneous mixing of faeces.
• Nevertheless, the pooled FEC strategy helped reduce antihelmintic costs by 80% within four years, illustrating both the economic and treatment efficacy of the FEC-based approach.

The Implications of the Study

• The research provides an economic framework guiding FEC-based strategies which can lead to significant cost savings in equine healthcare.
• The findings that pooling strategies should ideally not exceed 10 ponies can also guide field application of these strategies to ensure their effectiveness.
• The evidence that antihelmintic costs can be reduced by 80% will encourage more adoption of FEC-based treatments, thus making a considerable impact on dealing with drug-resistant parasitic infections in horses.