EQUUS - - Medical Front -

Man­age­ment mea­sures such as switch­ing to wood or pa­per bed­ding and steam­ing hay ra­tions can cut down on the lev­els of fungi in a horse’s en­vi­ron­ment, re­duc­ing the risk of in­flam­ma­tory air­way dis­ease (IAD), ac­cord­ing to a new study from Bel­gium.

“IAD is a milder form of res­pi­ra­tory dis­ease, which does not trans­late into such se­vere signs as seen with re­cur­rent air­way ob­struc­tion (RAO), but which none­the­less re­duces the horse’s breath­ing ca­pac­ity and, as a con­se­quence, his ca­pac­ity to ex­er­cise and per­form,” ex­plains Em­manuelle van Erck-Wester­gren, DVM, PhD, of the Equine Sports Medicine Prac­tice in Water­loo. “Some sci­en­tists think that IAD can be a pre­cur­sor to RAO.”

The role of en­vi­ron­men­tal dust in trig­ger­ing res­pi­ra­tory dis­ease is well doc­u­mented, and one com­po­nent of dust is fungi. To de­ter­mine the role of fungi in the devel­op­ment of IAD, van Erck-Wester­gren and her col­leagues col­lected data on 731 horses re­ferred to their prac­tice for res­pi­ra­tory dis­ease or poor per­for­mance.

Each horse was given a full clin­i­cal exam, which in­cluded en­doscopy of the air­way, along with a tra­cheal wash and bron­choalve­o­lar lavage to re­trieve bac­te­ria and fungi from the air­ways and lungs. The re­searchers also col­lected man­age­ment in­for­ma­tion, in­clud­ing the type of bed­ding used and the for­ages that the horses were fed---dry hay, moist­ened hay, steamed hay or hay­lage. Hay was steamed us­ing a com­mer­cial haysteam­ing sys­tem de­signed for that pur­pose.

The data showed that 89 per­cent of the study horses had IAD. Over­all, “fun­gal

The role of dust in trig­ger­ing res­pi­ra­tory dis­ease in horses is well-doc­u­mented, and one com­po­nent of dust is fungi.

el­e­ments” were found in tra­cheal wash fluid of 81 per­cent of IAD-pos­i­tive horses and 65 per­cent of non-IAD horses. Horses har­bor­ing fun­gal el­e­ments were about twice as likely to de­velop IAD than were those who did not. These find­ings, the re­searchers say, sup­port the idea that aerosolize­d fun­gal el­e­ments play a role in the devel­op­ment of IAD just as they do with RAO.

The re­searchers also iden­ti­fied man­age­ment prac­tices that can ex­ac­er­bate or mit­i­gate the ef­fects of fungi on the horse’s res­pi­ra­tory sys­tem. The de­gree of lower air­way in­flam­ma­tion, mea­sured by the amount of white blood cells cap­tured in the bron­choalve­o­lar lavage, was sig­nif­i­cantly higher when horses were bed­ded on straw ver­sus shav­ings, or when fed dry hay ver­sus steamed hay.

Specif­i­cally, horses fed with dry hay had 2.7 times more chances of be­ing di­ag­nosed with IAD com­pared to those who re­ceived steamed hay. Steam­ing de­creased the like­li­hood of find­ing fun­gal el­e­ments in tra­cheal washes by a fac­tor of two. Soak­ing hay did not in­flu­ence the find­ings of fun­gal el­e­ments.

van Erck-Wester­gren says that con­trol­ling a horse’s en­vi­ron­ment to help elim­i­nate fungi can al­low the horse to clear the or­gan­isms or spores present in his air­ways. “In­hala­tion with saline or sci­en­tif­i­cally tested es­sen­tial oils can help ac­cel­er­ate clear­ance,” she adds. “When the fungi have started to pro­lif­er­ate within the air­ways [in a horse with de­creased im­mu­nity or strong en­vi­ron­men­tal bur­den], anti-fun­gal treat­ment can be in­di­cated.”

Ref­er­ence: “Fungi in res­pi­ra­tory sam­ples of horses with in­flam­ma­tory air­way dis­ease,” Jour­nal of Vet­eri­nary In­ter­nal Medicine, De­cem­ber 2018

Air­borne fun­gal el­e­ments con­trib­ute to the devel­op­ment of in­flam­ma­tory air­way dis­ease, which can in­hibit per­for­mance.

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.