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Agriculture and Agriculture et. Agri-Food Canada Agroalimentaire Canada. Infrared thermography and heart rate variability for non-invasive assessment of animal welfare. ANZCCART 2008. Mairi Stewart Jim Webster, Kevin Stafford & Allan Schaefer. What is infrared thermography ?.
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Agriculture and Agriculture et Agri-Food Canada Agroalimentaire Canada Infrared thermography and heart rate variability for non-invasive assessment of animal welfare.ANZCCART 2008 Mairi Stewart Jim Webster, Kevin Stafford & Allan Schaefer
What is infrared thermography ? • Measures emitted radiated heat (represents 40-60% of heat loss from an animal) • Non-invasive – images collected from a distance • Can detect changes in heat loss during stress (due to regulation of peripheral blood flow)
You can't hide your lying eyes… Photo from U.S. Department of Defence Polygraph
Approach Measure responses to routine husbandry procedures used on-farm (eg handling, disbudding)
Autonomic Nervous System Parasympathetic Sympathetic Restores energy reserves Mobilises energy reserves - vasoconstriction - secretion of catecholamines -vasodilation
What is heart rate variability? • Non-invasive • Cardiac interbeat (RR) interval = time between successive R waves • Provides more accurate measure of stress than heart rate • Allows measurement of sympathetic and parasympathetic responses Components of theECG
Heart rate variability - disbudding- Sympathetic Nervous System Indicator ***
Disbud LA baseline Eye temperature - disbudding *** *** * Time (min) vasoconstriction
Summary • Eye temperature dropped in response to: • fright • painful procedure • adrenaline • Evidence that the drop in eye temperature is mediated by sympathetic activity
Conclusions • A combination of eye temperature and HRV is a useful non-invasive assessment of autonomic activity. • May be an alternative to invasive methods currently used to assess farm animal welfare.