Reliability of methods to determine cutaneous evaporative water loss rate in furred and fleeced mammals

Author(s)

Carvalho Fonseca, Vinicius de Franca ^{[1, 2]} ; da Silva, Roberto Gomes ^[3] ; Moura, Gustavo A. B. ^[3] ; Snelling, Edward P. ^{[1, 4, 5]} ; Fuller, Andrea ^{[1, 5]} ; Mitchell, Duncan ^[1] ; de Melo Costa, Cintia C. ^[3] ; Milan, Hugo M. ^[3] ; Maia, Alex S. C. ^[3]

Affiliation

^[1] Univ Witwatersrand, Sch Physiol, Brain Funct Res Grp, Johannesburg - South Africa

^[2] Univ Fed Paraiba, Anim Sci Dept, Innovat Grp Biometeorol & Anim Welf, BR-58397000 Areia - Brazil

^[3] Univ Estadual Paulista, Anim Sci Dept, Innovat Grp Biometeorol & Anim Welf, Jaboticabal - Brazil

^[4] Univ Pretoria, Fac Vet Sci, Dept Anat & Physiol, Onderstepoort - South Africa

^[5] Univ Pretoria, Fac Vet Sci, Ctr Vet Wildlife Res, Onderstepoort - South Africa

• Document type: Journal article
• Source: JOURNAL OF EXPERIMENTAL ZOOLOGY PART A-ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY; DEC 2021.
• Web of Science Citations: 0

Abstract

We used a high-precision weighing system and flow-through respirometry to quantify cutaneous evaporative water loss rates in woolly sheep (wool thickness, ca. 6.5 cm) and haired goats (coat thickness, ca. 2.5 cm), while simultaneously recording parallel data obtained from (1) a flow-through ventilated capsule, (2) a closed hand-held electronic evaporimeter chamber, and (3) a closed colorimetric paper disc chamber. In comparison to the weighing system and respirometry, used here as a ``gold standard{''} measure of cutaneous evaporative water loss rate, we found relatively good agreement with data obtained from the flow-through ventilated capsules. However, we found poor agreement with data obtained from the closed electronic evaporimeter chambers (underestimated by 60%, on average) and the closed colorimetric paper disc chambers (overestimated by 52%, on average). This deviation was likely associated with a requirement for shaved skin in the closed chamber methods. Our results therefore cast doubt on the validity of the closed chamber methods for measurement of cutaneous evaporative water loss rates in furred and fleeced mammals, and instead show that more accurate values can be obtained using flow-through ventilated capsules. (AU)

• FAPESP's process: 16/12278-1 - Evaluation of different methods for the measurement of heat loss by cutaneous evaporation in animals
• Grantee: Vinícius de França Carvalho Fonsêca
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/12218-4 - Thermal physiological responses of animals: challenges to obtain these measures in field
• Grantee: Vinícius de França Carvalho Fonsêca
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor