Equine laminitis: cryotherapy reduces the severity of the acute lesion.
BACKGROUND
The hypometabolic and vasoconstrictive effects of cryotherapy could prevent the development of laminitis.


OBJECTIVE
To use distal limb cryotherapy to prevent laminitis induced by alimentary carbohydrate overload.


METHODS
Laminitis was induced in 6 Standardbred horses that had one front limb continuously cooled in an ice/water mixture. Lameness evaluation, blinded lamellar histological grading and analysis for lamellar matrix metalloproteinase-2 (MMP-2) mRNA expression were used to evaluate the severity of laminitis.


RESULTS
Cryotherapy was well tolerated and effective in cooling the feet. In each horse no lameness was observed in the treated limbs. Laminitis histology scores in the treated limbs were significantly less than those of the corresponding untreated forelimbs (P < 0.05). Laminitis histology scores in the treated limbs were also significantly less than those of the untreated limbs (fore- and hind) as a group (P < 0.05). Expression of MMP-2 mRNA in the iced feet was significantly (P < 0.05) less than that detected in the untreated feet.


CONCLUSIONS
Cryotherapy, when applied to one foot, markedly reduced the severity of acute laminitis in this study. We propose that vasoconstriction (preventing delivery of haematogenous trigger factors) and hypometabolism (reduction in lamellar MMP activity) were the primary therapeutic mechanisms.


CONCLUSIONS
Although further research is needed, we suggest cryotherapy as a potentially effective prophylactic strategy in horses at risk of developing acute laminitis.
van Eps
A W
AW
Australian Equine Laminitis Research Unit, School of Veterinary Science, Faculty of Natural Resources Agriculture and Veterinary Science, The University of Queensland, St. Lucia, Queensland 4072, Australia.
Pollitt
C C
CC
D000818:Animals; D017679:Cryotherapy / Q000009:adverse effects / Q000379:methods / Q000662:veterinary*; D005260:Female; D005534:Foot Diseases / Q000473:pathology / Q000517:prevention & control / Q000628:therapy / Q000662:veterinary*; D015971:Gene Expression Regulation, Enzymologic; D006724:Hoof and Claw / Q000098:blood supply / Q000201:enzymology / Q000473:pathology*; D006734:Horse Diseases / Q000473:pathology / Q000517:prevention & control / Q000628:therapy*; D006736:Horses; D007249:Inflammation / Q000473:pathology / Q000517:prevention & control / Q000628:therapy / Q000662:veterinary; D007794:Lameness, Animal / Q000453:epidemiology; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D012449:Safety; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014661:Vasoconstriction / Q000502:physiology
D012333:RNA, Messenger; D020778:Matrix Metalloproteinase 2