Markers of respiratory inflammation in horses in relation to seasonal changes in air quality in a conventional racing stable
2008 (English)In: Canadian Journal of Veterinary Research-Revue Canadienne de Recherche Veterinaire, ISSN 0830-9000, Vol. 72, no 5, 432-439 p.Article in journal (Refereed) Published
Airborne factors in a conventionally managed racing stable and markers of pulmonary inflammation in the stabled horses were investigated on 3 occasions at 6-month intervals, including 2 winter periods and the intervening summer period. The stable measurements included inside and outside ambient temperature and relative humidity, levels of total and respirable dust, endotoxin, and 1,3-beta-glucan. Horses (n = 12) were examined in detail clinically as well as by endoscopy, bronchoalveolar lavage (BAL) cytology, and real-time polymerase chain reaction (RT-PCR) analysis of BAL-cells for IL-6 and IL-10 mRNA. Indoor measurements showed low dust levels irrespective of season. Inhalable dust, as well as 1,3-beta-glucan, were higher during the winter stabling period, whereas endotoxin levels were higher during summer. Complete data from all sampling occasions to be used for further evaluation was obtained for only 8 of the horses. There was a trend for elevation of BAL neutrophils in the horses during winter stabling that coincided with a 3.7-fold increased expression of IL-6 mRNA in BAL cells (P = 0.014). Compared to summer sampling, IL-10 mRNA expression was significantly upregulated in only 1 of the winter sampling occasions, implicating influence on immune regulation by factor/s apart from seasonal differences. Our findings suggest up-regulation of innate immunity in the airways of stabled horses; in particular involving IL-6 in association with mild elevations in respirable dust, 1,3-beta-glucan, and/or cold ambient air. However, given that this study was observational, other unmeasured environmental factors associated with winter stabling need to be considered.
Place, publisher, year, edition, pages
2008. Vol. 72, no 5, 432-439 p.
IdentifiersURN: urn:nbn:se:uu:diva-88200ISI: 000260451600009PubMedID: 19086376OAI: oai:DiVA.org:uu-88200DiVA: diva2:139570