Objective—To evaluate effects of thrombophlebitis of 1 or both jugular veins on athletic performance of horses.
Design—Retrospective case series.
Animals—91 horses with jugular vein thrombophlebitis.
Procedures—Medical records of horses with jugular vein thrombophlebitis examined between 1988 and 2005 were reviewed for signalment, history, clinical signs, diagnosis, and treatment. Performance was evaluated in 2 ways. A questionnaire was used to obtain a subjective assessment from the owner or trainer of the horse's performance after thrombophlebitis, compared with the performance before thrombophlebitis. Racing records from before and after thrombophlebitis were also evaluated.
Results—Thrombophlebitis was diagnosed in 37 horses at the time of admission (group 1), and 54 horses developed thrombophlebitis during hospitalization for an unrelated medical condition (group 2). Twenty-seven of 81 (33%) owners answered the questionnaire, and racing records were available for 31 horses. Performance data were available for 48 horses. Owners reported that all nonracing horses, except 1, had equivalent or better performances after discharge. Twenty-six of 31 (84%) Standardbreds resumed racing; in these horses, there was no significant difference between racing times before and after thrombophlebitis. No significant difference in performance was detected regardless of the primary disease, whether a horse had unilateral or bilateral thrombophlebitis, or the treatment administered.
Conclusions and Clinical Relevance—Results suggested that the athletic performance of horses used for nonracing events was not affected by thrombophlebitis. Thrombophlebitis in racing Standardbreds was associated with a decreased chance of return to racing; however, performance was not impaired in those that resumed racing.
The objectives of this study were to quantify lymphocytes and eosinophils in the mucosa of the duodenum and rectum in asthmatic horses.
8 healthy and 10 asthmatic horses.
Asthmatic horses were evaluated in a symptomatic (after 6 weeks of exposure to moldy hay) and asymptomatic status (3 and 7 months after being fed alfalfa pellets [n = 4] or treated with inhaled fluticasone ). Duodenal and rectal biopsies were endoscopically (n = 4 to 6) taken in each horse. Eosinophils were counted on slides stained with hematoxylin, eosin, phloxine, and saffron, and immunohistochemistry was used to evaluate T and B lymphocytes using CD3 and CD20, respectively.
The duodenal and rectal epithelium of asthmatic and control horses contained exclusively T lymphocytes (CD3). Symptomatic asthmatic horses, compared to controls, had a significantly higher number of T lymphocytes (CD3) in the duodenal epithelium (P = .016) and the adjacent lamina propria of the villi (P = .04). Compared to symptomatic asthmatic horses, the fluticasone-treated group had significantly fewer T lymphocytes in the total lamina propria of the rectal mucosa (P < .01).
Taken together, these results suggest that asthmatic horses have greater infiltration of T lymphocytes in the duodenal and rectal mucosa, indicating a certain degree of inflammation, which could be due to a systemic inflammatory effect and/or a local effect of ingested hay allergens in asthmatic horses. Systemic markers of inflammation have not been investigated to better qualify if the infiltration noted is due to a local and/or systemic effect.