Cargando…

Evaluation of the Thermal Response of the Horns in Dairy Cattle

SIMPLE SUMMARY: The horns of dairy cows are typically removed at a young age. However, surprisingly little is known about the biological function and the role of horns in the regulation of body temperature, or about the potential effects of horn removal for the cow. Farmers reported that horns get w...

Descripción completa

Detalles Bibliográficos
Autores principales: Algra, Marijke, de Keijzer, Lara, Arndt, Saskia S., van Eerdenburg, Frank J. C. M., Goerlich, Vivian C.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9913495/
https://www.ncbi.nlm.nih.gov/pubmed/36766390
http://dx.doi.org/10.3390/ani13030500
_version_ 1784885441660452864
author Algra, Marijke
de Keijzer, Lara
Arndt, Saskia S.
van Eerdenburg, Frank J. C. M.
Goerlich, Vivian C.
author_facet Algra, Marijke
de Keijzer, Lara
Arndt, Saskia S.
van Eerdenburg, Frank J. C. M.
Goerlich, Vivian C.
author_sort Algra, Marijke
collection PubMed
description SIMPLE SUMMARY: The horns of dairy cows are typically removed at a young age. However, surprisingly little is known about the biological function and the role of horns in the regulation of body temperature, or about the potential effects of horn removal for the cow. Farmers reported that horns get warmer during rumination, and studies on goats indicate that horns help with the regulation of body temperature. To study the possible function of horns in the regulation of body temperature in dairy cows, we used infrared thermography to measure the superficial temperature of the horns, eyes, and ears of 18 cows on three different farms in the Netherlands. Social and non-social behaviours of these cows were registered as well. Based on environmental temperature, humidity, and wind speed, the heat load index (HLI) was calculated as a measure of the heat load experienced by a cow. The temperature of the horns rose by 0.18 °C per unit HLI, indicating that the horns serve to lose heat. Dehorned cows had higher eye temperatures than horned cows, though this result may not be reliable due to the low sample size and experimental setup. We did not, however, find changes in horn temperature during rumination, nor with any other behaviours. Our study supports a role of horns in the regulation of body temperature, but not related to rumination. These results should be considered when measuring the potential effects of horn removal, a painful procedure. ABSTRACT: Dairy cattle are typically disbudded or dehorned. Little is known, however, about the biological function and role of horns during thermoregulatory processes in cattle, and thus about the potential physiological consequences of horn removal. Anecdotal evidence suggests that dairy cow horns increase in temperature during rumination, and few studies on other bovid species indicate that horns aid thermoregulation. The objective of this study was, therefore, to elucidate a possible thermoregulatory function of the horns in dairy cattle. Using non-invasive infrared thermography, we measured the superficial temperature of the horns, eyes, and ears of 18 focal cows on three different farms in a temperate climate zone under various environmental circumstances. Observations of social and non-social behaviours were conducted as well. Based on environmental temperature, humidity, and wind speed, the heat load index (HLI) was calculated as a measure of the heat load experienced by a cow. The temperature of the horns increased by 0.18 °C per unit HLI, indicating that horns serve the dissipation of heat. Dehorned cows had higher eye temperatures than horned cows, though this result should be interpreted with caution as the low sample size and experimental setup prevent casual conclusions. We did not, however, find changes in horn temperature during rumination, nor with any other behaviours. Our study thus supports a role of horns in thermoregulation, but not related to rumination. These results should be considered when assessing the potential consequences of horn removal, a painful procedure.
format Online
Article
Text
id pubmed-9913495
institution National Center for Biotechnology Information
language English
publishDate 2023
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-99134952023-02-11 Evaluation of the Thermal Response of the Horns in Dairy Cattle Algra, Marijke de Keijzer, Lara Arndt, Saskia S. van Eerdenburg, Frank J. C. M. Goerlich, Vivian C. Animals (Basel) Article SIMPLE SUMMARY: The horns of dairy cows are typically removed at a young age. However, surprisingly little is known about the biological function and the role of horns in the regulation of body temperature, or about the potential effects of horn removal for the cow. Farmers reported that horns get warmer during rumination, and studies on goats indicate that horns help with the regulation of body temperature. To study the possible function of horns in the regulation of body temperature in dairy cows, we used infrared thermography to measure the superficial temperature of the horns, eyes, and ears of 18 cows on three different farms in the Netherlands. Social and non-social behaviours of these cows were registered as well. Based on environmental temperature, humidity, and wind speed, the heat load index (HLI) was calculated as a measure of the heat load experienced by a cow. The temperature of the horns rose by 0.18 °C per unit HLI, indicating that the horns serve to lose heat. Dehorned cows had higher eye temperatures than horned cows, though this result may not be reliable due to the low sample size and experimental setup. We did not, however, find changes in horn temperature during rumination, nor with any other behaviours. Our study supports a role of horns in the regulation of body temperature, but not related to rumination. These results should be considered when measuring the potential effects of horn removal, a painful procedure. ABSTRACT: Dairy cattle are typically disbudded or dehorned. Little is known, however, about the biological function and role of horns during thermoregulatory processes in cattle, and thus about the potential physiological consequences of horn removal. Anecdotal evidence suggests that dairy cow horns increase in temperature during rumination, and few studies on other bovid species indicate that horns aid thermoregulation. The objective of this study was, therefore, to elucidate a possible thermoregulatory function of the horns in dairy cattle. Using non-invasive infrared thermography, we measured the superficial temperature of the horns, eyes, and ears of 18 focal cows on three different farms in a temperate climate zone under various environmental circumstances. Observations of social and non-social behaviours were conducted as well. Based on environmental temperature, humidity, and wind speed, the heat load index (HLI) was calculated as a measure of the heat load experienced by a cow. The temperature of the horns increased by 0.18 °C per unit HLI, indicating that horns serve the dissipation of heat. Dehorned cows had higher eye temperatures than horned cows, though this result should be interpreted with caution as the low sample size and experimental setup prevent casual conclusions. We did not, however, find changes in horn temperature during rumination, nor with any other behaviours. Our study thus supports a role of horns in thermoregulation, but not related to rumination. These results should be considered when assessing the potential consequences of horn removal, a painful procedure. MDPI 2023-01-31 /pmc/articles/PMC9913495/ /pubmed/36766390 http://dx.doi.org/10.3390/ani13030500 Text en © 2023 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Algra, Marijke
de Keijzer, Lara
Arndt, Saskia S.
van Eerdenburg, Frank J. C. M.
Goerlich, Vivian C.
Evaluation of the Thermal Response of the Horns in Dairy Cattle
title Evaluation of the Thermal Response of the Horns in Dairy Cattle
title_full Evaluation of the Thermal Response of the Horns in Dairy Cattle
title_fullStr Evaluation of the Thermal Response of the Horns in Dairy Cattle
title_full_unstemmed Evaluation of the Thermal Response of the Horns in Dairy Cattle
title_short Evaluation of the Thermal Response of the Horns in Dairy Cattle
title_sort evaluation of the thermal response of the horns in dairy cattle
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9913495/
https://www.ncbi.nlm.nih.gov/pubmed/36766390
http://dx.doi.org/10.3390/ani13030500
work_keys_str_mv AT algramarijke evaluationofthethermalresponseofthehornsindairycattle
AT dekeijzerlara evaluationofthethermalresponseofthehornsindairycattle
AT arndtsaskias evaluationofthethermalresponseofthehornsindairycattle
AT vaneerdenburgfrankjcm evaluationofthethermalresponseofthehornsindairycattle
AT goerlichvivianc evaluationofthethermalresponseofthehornsindairycattle