Non-Invasive Sheep Biometrics Obtained by Computer Vision Algorithms and Machine Learning Modeling Using Integrated Visible/Infrared Thermal Cameras.

Sigfredo Fuentes,Frank R Dunshea,Eden Tongson,Aleena Joy,Claudia Gonzalez Viejo,Surinder S Chauhan

doi:10.3390/s20216334

Sigfredo Fuentes, Frank R Dunshea + Show 4 more

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https://doi.org/10.3390/s20216334

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Abstract

Live sheep export has become a public concern. This study aimed to test a non-contact biometric system based on artificial intelligence to assess heat stress of sheep to be potentially used as automated animal welfare assessment in farms and while in transport. Skin temperature (°C) from head features were extracted from infrared thermal videos (IRTV) using automated tracking algorithms. Two parameter engineering procedures from RGB videos were performed to assess Heart Rate (HR) in beats per minute (BPM) and respiration rate (RR) in breaths per minute (BrPM): (i) using changes in luminosity of the green (G) channel and (ii) changes in the green to red (a) from the CIELAB color scale. A supervised machine learning (ML) classification model was developed using raw RR parameters as inputs to classify cutoff frequencies for low, medium, and high respiration rate (Model 1). A supervised ML regression model was developed using raw HR and RR parameters from Model 1 (Model 2). Results showed that Models 1 and 2 were highly accurate in the estimation of RR frequency level with 96% overall accuracy (Model 1), and HR and RR with R = 0.94 and slope = 0.76 (Model 2) without statistical signs of overfitting

Highlights

Live animal exports have been lately under scrutiny by the public and animal welfare advocates [1], especially live export though shipping, related to welfare conditions and heat stress during long trips up to six weeks by sea, which in extreme cases can result in the death of animals in rates up to 2–3.8% [2]
Heat stress events for animals are restricted to animal transport through sea or land, but it can happen in farms due to increased ambient temperatures related to climate change, which can directly impact the health and welfare of animals [4,5,6,7]
The temperature-humidity index (THI) can be coupled with direct assessment of the effects of heat stress using physiological responses through manual monitoring [17,18], using sensors directly located on animals [19], behavioral assessments or including molecular, cellular and metabolic biomarkers [20,21,22]

Summary

Introduction

Live animal exports have been lately under scrutiny by the public and animal welfare advocates [1], especially live export though shipping, related to welfare conditions and heat stress during long trips up to six weeks by sea, which in extreme cases can result in the death of animals in rates up to 2–3.8% [2]. The THI can be coupled with direct assessment of the effects of heat stress using physiological responses through manual monitoring [17,18], using sensors directly located on animals [19], behavioral assessments or including molecular, cellular and metabolic biomarkers [20,21,22]. The use of intravaginal/rectal devices or contact sensors can be stressful for the animals [23]

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