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PloS one2024; 19(5); e0303092; doi: 10.1371/journal.pone.0303092

Hematological and physiological responses in polo ponies with different field-play positions during low-goal polo matches.

Abstract: Strenuous exercise in traditional polo matches creates enormous stress on horses. Hematological and physiological measures may vary across different field-play positions. This study aimed to investigate the effort intensity and the impact of exertion on hematology and heart rate variability (HRV) in polo ponies with different positions. Thirty-two ponies, divided equally into eight teams, were studied. Each comprises forwards (number 1), midfielders (numbers 2 and 3), and defenders (number 4). Team pairs played the first chukka in four low-goal polo matches. Percent maximum heart rate (%HRmax), indicating ponies' effort intensity, was classified into five zones, including zones 1 (95%). Hematological and HRV parameters were determined before, immediately after, and at 30-minute intervals for 180 minutes after chukkas; HRV variables were also obtained during warm-up and exercise periods. Results indicated that the number two ponies spent more time in zone 4 (p < 0.05) but less in zone 2 (p < 0.01) than the number four ponies. Cortisol levels increased immediately and 30 minutes afterward (p < 0.0001 for both) and then returned to baseline 60-90 minutes after exertion. Other measures (Hct, Hb, RBC, WBC, neutrophils, and CK enzyme) increased immediately (p < 0.0001 for all) and lasted at least 180 minutes after exertion (p < 0.05-0.0001). HRV decreased during the chukka until approximately 90 minutes afterward (p < 0.05-0.0001). The stress index increased during the chukka and declined to baseline at 60 minutes in number 1-3 ponies but lasted 90 minutes in those at number four. Effort intensity distribution differed among field-play positions. Decreased HRV indicated reduced parasympathetic activity during exercise, extending to 90 minutes after exertion in polo ponies. Defenders seem to experience more stress than those in other positions.
Publication Date: 2024-05-16 PubMed ID: 38753824PubMed Central: PMC11098493DOI: 10.1371/journal.pone.0303092Google Scholar: Lookup
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  • Journal Article

Summary

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This study examines how strenuous exercise during low-goal polo matches impact different hematology and heart rate measures in horses according to their playing position. The results indicate that stress significant varies depending on the positions the horses play.

Study Design

  • The research involved 32 polo ponies, divided into eight teams. Each team included forwards (number 1), midfielders (numbers 2 and 3), and defenders (number 4).
  • A continuous heart rate monitor was used on the animals to calculate the percent maximum heart rate (%HRmax), which indicated the ponies’ effort intensity during the matches.
  • Hematological and heart rate variability (HRV) parameters were determined before, immediately after, and at 30-minute intervals for 180 minutes following the matches.
  • Key physiological variables such as cortisol levels, white blood cell counts, red blood cell counts, neutrophil counts, and others were measured.

Key Findings

  • The midfield ponies (number 2) were found to spend more time in zone 4 of %HRmax and less time in zone 2 compared to defender ponies (number 4), implying a higher exertion level for midfield ponies.
  • Immediately after exertion, cortisol levels increased, reflecting immediate stress response. These levels then returned to baseline roughly 60-90 minutes post exertion.
  • Other hematological measures such as hematocrit (Htc), hemoglobin (Hb), red and white blood cells (RBC and WBC), neutrophils, and creatine kinase (CK) enzyme levels also increased immediately after the matches.
  • Heart rate variability (HRV) was observed to decrease during and for approximately 90 minutes following the matches in all ponies, suggesting a decrease in parasympathetic nervous system activity during intense exercise.
  • Interestingly, the stress index increased during the game and declined to baseline only after 60 minutes in all ponies except for defenders where it lasted up to 90 minutes, indicating defenders appear to experience more stress than other playing positions.

Conclusions and Implications

  • The different levels of physical exertion and stress responses in ponies in different field-play positions were noted, with defender ponies suffering greater stress.
  • The results provide valuable insights into the impact of polo matches on horses’ physiology, which can guide the development of better training plans and health checks for polo ponies to ensure optimal performance and welfare.

Cite This Article

APA
Sanigavatee K, Poochipakorn C, Huangsaksri O, Wonghanchao T, Yalong M, Poungpuk K, Thanaudom K, Chanda M. (2024). Hematological and physiological responses in polo ponies with different field-play positions during low-goal polo matches. PLoS One, 19(5), e0303092. https://doi.org/10.1371/journal.pone.0303092

Publication

ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 19
Issue: 5
Pages: e0303092
PII: e0303092

Researcher Affiliations

Sanigavatee, Kanokpan
  • Veterinary Clinical Study Program, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
  • Department of Large Animal and Wildlife Clinical Science, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
Poochipakorn, Chanoknun
  • Veterinary Clinical Study Program, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
  • Department of Large Animal and Wildlife Clinical Science, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
Huangsaksri, Onjira
  • Veterinary Clinical Study Program, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
  • Department of Large Animal and Wildlife Clinical Science, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
Wonghanchao, Thita
  • Veterinary Clinical Study Program, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
  • Department of Large Animal and Wildlife Clinical Science, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
Yalong, Mona
  • Veterinary Science Program, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
Poungpuk, Kanoknoot
  • Veterinary Science Program, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
Thanaudom, Kemika
  • Veterinary Science Program, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
Chanda, Metha
  • Department of Large Animal and Wildlife Clinical Science, Faculty of Veterinary Medicine, Kasetsart University, Kampaeng Saen Campus, Nakorn Pathom, Thailand.
  • Thailand Equestrian Federation, Sports Authority of Thailand, Bangkok, Thailand.

MeSH Terms

  • Horses
  • Animals
  • Heart Rate / physiology
  • Physical Conditioning, Animal / physiology
  • Hydrocortisone / blood
  • Hydrocortisone / metabolism
  • Physical Exertion / physiology
  • Male

Conflict of Interest Statement

The authors have declared that no competing interests exist.

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