Multivariate analysis for characteristics of heat tolerance in horses in Brazil.
Abstract: The environment in which the horse is reared affects its ability to maintain thermal balance which is in turn related to thermal characteristics and regulatory physiological mechanisms. In this study a multivariate analysis of physiological traits in relation to heat tolerance in horses was carried out in the Federal District, Brazil. The aim was to test the ability of these analyses to separate groups of animals and determine which physiological traits are most important in the adaptation to heat stress. Forty adult horses (4 to 13 years) were used, ten from each of four different genetic groups (English thoroughbred, Brazilian showjumper, crossbred and Breton). The traits examined included heart and breathing rate, rectal temperature as well as blood parameters. The data underwent multivariate statistical analysis including cluster, discriminate and canonical using Statistical Analysis System - SAS (R) procedures CLUSTER, STEPDISC, CANCORR and DISCRIM. The tree diagram showed clear distances between groups studied and canonical analysis was able to separate individuals in groups. The discriminate analysis identified the variables which were most important in separating these groups. The multivariate analysis was able to separate the animals into groups with RR, HR and RT being important in this separation.
Publication Date: 2009-07-07 PubMed ID: 19579053DOI: 10.1007/s11250-009-9404-xGoogle Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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The research investigates the physiological traits associated with heat tolerance in four different horse breeds in Brazil using multivariate analysis.
Context and Aim
- The study examines how a horse’s natural environment influences its ability to maintain thermal balance.
- The focus mainly lies on identifying key physiological traits that contribute to their adaptation to heat stress.
- The investigation is conducted in the Federal District, Brazil, where forty adult horses from four genetic groups participate – English thoroughbred, Brazilian showjumper, crossbred and Breton.
Methods and Procedure
- Different traits such as heart rate, breathing rate, rectal temperature, blood parameters are considered for the study.
- A multivariate analysis involving cluster, discriminant and canonical analysis is performed on these traits.
- Techniques such as CLUSTER, STEPDISC, CANCORR and DISCRIM from Statistical Analysis System – SAS (R) are used for this analysis.
Findings
- The tree diagram resulting from the cluster analysis demonstrated significant distances between the groups studied, indicating distinct physiological responses to heat between the different breeds.
- The canonical analysis efficiently separated the individual horses into their associated groups, showing that group differences could be seen at an individual level.
- The discriminant analysis identified the most impactful variables in creating these separations. The variables that stood out in this separation were the respire rate (RR), heart rate (HR), and the rectal temperature (RT).
Conclusion
- The research successfully uses multivariate analysis to discern differences in heat tolerance among the four horse breeds.
- The specific physiological traits of respire rate, heart rate and rectal temperature were found to play vital roles in helping these animals tolerate heat.
- The study indicates the importance of considering individual physiological traits in understanding how different horses adapt to high temperatures.
Cite This Article
APA
Castanheira M, Paiva SR, Louvandini H, Landim A, Fiorvanti MC, Paludo GR, Dallago BS, McManus C.
(2009).
Multivariate analysis for characteristics of heat tolerance in horses in Brazil.
Trop Anim Health Prod, 42(2), 185-191.
https://doi.org/10.1007/s11250-009-9404-x Publication
Researcher Affiliations
- Escola de Veterinária, Universidade Federal de Goiás, Goiânia, GO, Brazil. castanheira_m@hotmail.com
MeSH Terms
- Animals
- Body Temperature / physiology
- Body Temperature Regulation / physiology
- Brazil
- Discriminant Analysis
- Erythrocyte Count / veterinary
- Heart Rate / physiology
- Hematocrit / veterinary
- Hemoglobins / analysis
- Horses / physiology
- Hot Temperature / adverse effects
- Leukocyte Count / veterinary
- Respiration
- Tropical Climate
References
This article includes 5 references
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- Geor RJ, McCutcheon LJ, Ecker GL, Lindinger MI. Heat storage in horses during submaximal exercise before and after humid heat acclimation.. J Appl Physiol (1985) 2000 Dec;89(6):2283-93.
- Cheung SS, McLellan TM. Heat acclimation, aerobic fitness, and hydration effects on tolerance during uncompensable heat stress.. J Appl Physiol (1985) 1998 May;84(5):1731-9.
Citations
This article has been cited 9 times.- Trigg LE, Lyons S, Mullan S. Risk factors for, and prediction of, exertional heat illness in Thoroughbred racehorses at British racecourses. Sci Rep 2023 Mar 14;13(1):3063.
- Venkatesh KM, Mishra C, Pradhan SK, Behera K, Mishra SR, Nayak G. A novel heterozygote allele in caprine melanocortin 1 receptor (MC1R) gene: an association with heat stress traits. Trop Anim Health Prod 2023 Feb 7;55(2):68.
- de Faria DA, do Prado Paim T, Dos Santos CA, Paiva SR, Nogueira MB, McManus C. Selection signatures for heat tolerance in Brazilian horse breeds. Mol Genet Genomics 2022 Mar;297(2):449-462.
- Martin G, Yanez-Arenas C, Chen C, Plowright RK, Webb RJ, Skerratt LF. Climate Change Could Increase the Geographic Extent of Hendra Virus Spillover Risk. Ecohealth 2018 Sep;15(3):509-525.
- Zakari FO, Ayo JO, Rekwot PI, Kawu MU. Effect of age, sex, physical activity and meteorological factors on haematological parameters of donkeys (Equus asinus). Comp Clin Path 2016;25(6):1265-1272.
- Zakari FO, Ayo JO, Rekwot PI, Kawu MU. Effects of age and season on haematological parameters of donkeys during the rainy and cold-dry seasons. Int J Biometeorol 2015 Dec;59(12):1813-24.
- Correa MP, Dallago BS, Paiva SR, Canozzi ME, Louvandini H, Barcellos JJ, McManus C. Multivariate analysis of heat tolerance characteristics in Santa Inês and crossbred lambs in the Federal District of Brazil. Trop Anim Health Prod 2013 Aug;45(6):1407-14.
- Nowak AC, Macho-Maschler S, Biermann NM, Palme R, Dengler F. Investigating the interplay of stressors and health in horses through fecal cortisol metabolite analysis. Front Vet Sci 2025;12:1545577.
- Aragona F, Arfuso F, Fazio F, De Caro S, Giudice E, Monteverde V, Piccione G, Giannetto C. Circadian Variation of Peripheral Blood Cells in Horses Maintained in Different Environmental and Management Conditions. Animals (Basel) 2023 Jun 3;13(11).
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