Severity and effects of pharyngeal lymphoid hyperplasia vary with age and racetrack location in Thoroughbred racehorses

IF 0.6 Q3 VETERINARY SCIENCES

Comparative Exercise Physiology Pub Date : 2023-10-13 DOI:10.1163/17552559-20220070

J. Bagshaw, M. Sanz, Y. Wang, S. Shoemaker, W. Bayly

{"title":"Severity and effects of pharyngeal lymphoid hyperplasia vary with age and racetrack location in Thoroughbred racehorses","authors":"J. Bagshaw, M. Sanz, Y. Wang, S. Shoemaker, W. Bayly","doi":"10.1163/17552559-20220070","DOIUrl":null,"url":null,"abstract":"This study evaluated the severity of pharyngeal lymphoid hyperplasia (PLH) in relation to age, performance and geographic location of Thoroughbreds racing at 13 American racetracks. PLH severity (graded 1-4 with validated criteria related to size, appearance and coalescence of hyperplastic follicles) and tracheal mucus score (0-5) were determined from videoendoscopies recorded 30-60 min post-racing. There were 198 from 2-year-olds, including following graded stakes races, and 116 were from ≥2-year-old horses following graded races. Performance data was obtained from Thoroughbred racehorse databases. Associations between PLH and speed index, average race speed, mucus score, age, and track location were separately investigated for the 2-year-olds and for the stakes horses using Pearson’s Chi-squared independence test, ANOVA or an ordinal logistic regression model. was significant. There were age (PLH Grade ≥3 in 92% 2-year-olds, 88% for 3-year-olds and 52% in ≥4-year-olds; ) and track location () effects on PLH grade. In 2-year-olds, PLH varied with track location () and race day air quality index (AQI; ). Horses housed at the racetrack had higher PLH grades than horses transported to the race (). Speed index (), tracheal mucus () and average speed () were not associated with PLH severity in 2-year-olds. In stakes horses, severity of PLH was not different between 2- and 3-year-olds but decreased with age in ≥3-year-olds (). Higher PLH grades were associated with decreased speed index () but not average speed (). Track location () and mucus scores () were also associated with PLH grade in all stakes horses. PLH was most severe in 2- and 3-year-old stakes horses but did not impair their performance. Of stakes horses ≥4-years-old, those with PLH ≥3 performed worse than those with PLH ≤2. Racetrack location and AQI were associated with PLH severity in racehorses of all ages for reasons that require further study.","PeriodicalId":10709,"journal":{"name":"Comparative Exercise Physiology","volume":"37 1","pages":""},"PeriodicalIF":0.6000,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Comparative Exercise Physiology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1163/17552559-20220070","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"VETERINARY SCIENCES","Score":null,"Total":0}

引用次数: 0

Abstract

This study evaluated the severity of pharyngeal lymphoid hyperplasia (PLH) in relation to age, performance and geographic location of Thoroughbreds racing at 13 American racetracks. PLH severity (graded 1-4 with validated criteria related to size, appearance and coalescence of hyperplastic follicles) and tracheal mucus score (0-5) were determined from videoendoscopies recorded 30-60 min post-racing. There were 198 from 2-year-olds, including following graded stakes races, and 116 were from ≥2-year-old horses following graded races. Performance data was obtained from Thoroughbred racehorse databases. Associations between PLH and speed index, average race speed, mucus score, age, and track location were separately investigated for the 2-year-olds and for the stakes horses using Pearson’s Chi-squared independence test, ANOVA or an ordinal logistic regression model. was significant. There were age (PLH Grade ≥3 in 92% 2-year-olds, 88% for 3-year-olds and 52% in ≥4-year-olds; ) and track location () effects on PLH grade. In 2-year-olds, PLH varied with track location () and race day air quality index (AQI; ). Horses housed at the racetrack had higher PLH grades than horses transported to the race (). Speed index (), tracheal mucus () and average speed () were not associated with PLH severity in 2-year-olds. In stakes horses, severity of PLH was not different between 2- and 3-year-olds but decreased with age in ≥3-year-olds (). Higher PLH grades were associated with decreased speed index () but not average speed (). Track location () and mucus scores () were also associated with PLH grade in all stakes horses. PLH was most severe in 2- and 3-year-old stakes horses but did not impair their performance. Of stakes horses ≥4-years-old, those with PLH ≥3 performed worse than those with PLH ≤2. Racetrack location and AQI were associated with PLH severity in racehorses of all ages for reasons that require further study.

查看原文本刊更多论文

纯血赛马咽淋巴细胞增生症的严重程度和影响因年龄和赛马场位置而异

本研究评估了在美国 13 个赛马场比赛的纯血马的咽淋巴增生（PLH）严重程度与年龄、成绩和地理位置的关系。根据赛后 30-60 分钟的视频内窥镜记录，确定咽淋巴细胞增生的严重程度（根据增生滤泡的大小、外观和聚合度的相关验证标准分为 1-4 级）和气管粘液评分（0-5 分）。其中198匹马来自2岁马，包括参加分级赛的2岁马，116匹马来自参加分级赛的≥2岁马。赛马表现数据来自纯血马数据库。采用皮尔逊卡方独立性检验、方差分析或序数逻辑回归模型，分别研究了2岁马和分级赛马的PLH与速度指数、平均比赛速度、粘液得分、年龄和赛道位置之间的关系。年龄（92%的2岁马PLH等级≥3，88%的3岁马PLH等级≥3，52%的≥4岁马PLH等级≥3）和赛道位置（）对PLH等级有影响。在 2 岁马中，PLH 随赛道位置（）和比赛日空气质量指数（AQI；）的变化而变化。在赛马场饲养的马匹比运送到赛马场的马匹的PLH等级更高（）。速度指数（）、气管粘液（）和平均速度（）与两岁马的PLH严重程度无关。在赛马中，2岁和3岁马的PLH严重程度没有差异，但≥3岁马的PLH严重程度随年龄增长而降低（）。PLH等级越高，速度指数（）越低，但平均速度（）却不低。赛道位置（）和粘液评分（）也与所有赛马的 PLH 等级有关。PLH在2岁和3岁的赛马中最为严重，但并不影响它们的表现。在≥4岁的赛马中，PLH≥3的赛马比PLH≤2的赛马表现更差。赛马场位置和空气质量指数与各年龄段赛马的PLH严重程度有关，其原因有待进一步研究。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Comparative Exercise Physiology VETERINARY SCIENCES-

CiteScore

1.50

自引率

11.10%

发文量

期刊介绍： ''Comparative Exercise Physiology'' is the only international peer-reviewed scientific journal specifically dealing with the latest research in exercise physiology across all animal species, including humans. The major objective of the journal is to use this comparative approach to better understand the physiological, nutritional, and biochemical parameters that determine levels of performance and athletic achievement. Core subjects include exercise physiology, biomechanics, gait (including the effect of riders in equestrian sport), nutrition and biochemistry, injury and rehabilitation, psychology and behaviour, and breeding and genetics. This comparative and integrative approach to exercise science ultimately highlights the similarities as well as the differences between humans, horses, dogs, and other athletic or non-athletic species during exercise. The result is a unique forum for new information that serves as a resource for all who want to understand the physiological challenges with exercise.