Development of an Explainable Machine Learning Computational Model for the Prediction of Severe Complications After Orchiectomy in Stallions.
Abstract: The objective of the present study was to apply supervised Machine Learning to predict severe complications after equine orchiectomy. A dataset of 612 cases of orchiectomies in stallions was used for the development of a computational model, among which in 8.5% of cases severe complications (colic, continued stallion-like behaviour, evisceration, funiculitis, haemorrhage, and scrotal infection) were diagnosed post-orchiectomy. Three supervised Machine Learning tools were employed: Logistic Regression (12 different models evaluated), Random Forest (64 models), and Gradient Boosting (8 models). For the prediction of the development of severe complications post-orchiectomy, Logistic Regression was the tool that produced the best discrimination measures, where accuracy, precision and recall were 0.9134, 0.8391, and 0.9133, respectively. The results of the analysis for SHapley Additive exPlanations values for the impact of the independent variables in the prediction of the development of complications indicated that (a) the age of the horse and (b) the surgical technique employed were the two variables that mostly influenced the prediction outcome, findings that were unambiguous in the models developed by any Machine Learning tool. The findings of this study indicate that computational models could be used as adjunct tools to support clinical decisions in the peri-operative management of horses.
Publication Date: 2026-01-25 PubMed ID: 41681358PubMed Central: PMC12897072DOI: 10.3390/ani16030377Google Scholar: Lookup
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- Journal Article
Summary
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Overview
- This study developed and evaluated machine learning models to predict the risk of severe complications following orchiectomy (castration surgery) in stallions.
- The goal was to support veterinarians in making informed peri-operative decisions to improve stallion outcomes.
Background and Objective
- Orchiectomy in stallions can sometimes lead to serious post-surgical complications such as colic, abnormal behavior, evisceration, funiculitis, hemorrhage, and scrotal infection.
- Timely prediction of these complications before or immediately after surgery could help vets manage care proactively and potentially reduce adverse outcomes.
- The researchers aimed to leverage supervised machine learning methods to create a predictive computational model using clinical data from past stallion orchiectomies.
Data and Methods
- The dataset consisted of 612 cases of orchiectomies performed on stallions.
- Severe complications occurred in 8.5% of these surgeries.
- Three supervised machine learning algorithms were tested to predict severe complications:
- Logistic Regression (with 12 different model versions evaluated)
- Random Forest (64 models tested)
- Gradient Boosting (8 models tested)
Model Performance
- Logistic Regression outperformed both Random Forest and Gradient Boosting in predicting severe complications.
- Performance metrics for the best Logistic Regression model included:
- Accuracy: 0.9134 (indicating overall correct prediction rate)
- Precision: 0.8391 (how many predicted complications were true complications)
- Recall: 0.9133 (the model’s ability to identify all actual complications)
Interpreting Model Predictions: Explainability
- The researchers used SHapley Additive exPlanations (SHAP) values to interpret how each independent variable influenced model predictions.
- Two key factors consistently emerged as the strongest predictors of severe complications across all models:
- Age of the horse — older or younger age possibly linked to complication risk.
- Surgical technique used — differences in how the orchiectomy was conducted impacted outcomes.
- This explainability provides clinicians with insights that align with clinical understanding and helps justify reliance on the predictive model.
Conclusions and Implications
- The study demonstrates that machine learning models, particularly logistic regression, can effectively predict severe post-orchiectomy complications in stallions.
- Using explainable AI methods like SHAP enhances trust and facilitates clinical adoption by clarifying how input factors relate to risk.
- Such computational tools could serve as valuable adjuncts to support veterinary clinical decision-making, potentially improving peri-operative care plans and outcomes for horses undergoing orchiectomy.
- Further validation and integration into clinical workflows would be important next steps to realize practical benefits.
Cite This Article
APA
Tyrnenopoulou P, Kalatzis D, Kiouvrekis Y, Flouraki E, Folias L, Loukopoulos E, Starras A, Chalvatzis P, Tsioli V, Mavrogianni VS, Fthenakis GC.
(2026).
Development of an Explainable Machine Learning Computational Model for the Prediction of Severe Complications After Orchiectomy in Stallions.
Animals (Basel), 16(3), 377.
https://doi.org/10.3390/ani16030377 Publication
Researcher Affiliations
- Veterinary Faculty, University of Thessaly, 43100 Karditsa, Greece.
- Faculty of Public and One Health, University of Thessaly, 43100 Karditsa, Greece.
- Faculty of Public and One Health, University of Thessaly, 43100 Karditsa, Greece.
- Business School, University of Nicosia, Nicosia 1700, Cyprus.
- Department of Information Technologies, University of Limassol, Limassol 3020, Cyprus.
- Veterinary Faculty, University of Thessaly, 43100 Karditsa, Greece.
- Private Veterinary Practice, 41110 Larissa, Greece.
- Veterinary Faculty, University of Thessaly, 43100 Karditsa, Greece.
- Private Veterinary Practice, 73100 Chania, Greece.
- Private Veterinary Practice, 50100 Kozani, Greece.
- Veterinary Faculty, University of Thessaly, 43100 Karditsa, Greece.
- Veterinary Faculty, University of Thessaly, 43100 Karditsa, Greece.
- Veterinary Faculty, University of Thessaly, 43100 Karditsa, Greece.
Conflict of Interest Statement
The authors declare no conflicts of interest.
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