Dermatosparaxis in two White Dorper lambs

CASE HISTORY AND CLINICAL FINDINGS: Two White Dorper lambs from the North Island of New Zealand, 2 and 4 weeks of age, were presented with large skin flaps hanging from the flanks, separation of skin from the subcutis over mobile joints, and de-gloving injuries of the limbs and tail. The lambs were subject to euthanasia on humane grounds. PATHOLOGICAL FINDINGS: Large skin tears with associated haemorrhage, periarticular S/C oedema and generalised skin fragility were observed in both lambs at post-mortem examination. Histology of the affected skin revealed diffuse hyalinisation of dermal collagen compared with control lambs, protein-filled peri-adnexal clefts and areas of deep dermal and S/C granulation tissue consistent with previous separation of skin from the subcutis. Analysis of hair follicles, collected from one of the lambs, using a commercially available genetic test in Australia was consistent with the lamb being homozygous for the mutation responsible for ovine dermatosparaxis. DIAGNOSIS: Likely dermatosparaxis. CLINICAL RELEVANCE: These findings strongly suggest that the mutation responsible for dermatosparaxis in White Dorper sheep is present in New Zealand. Dermatosparaxis should be considered when investigating skin fragility in lambs with White Dorper genetics. Confirmation of the disorder is possible through genetic analysis of hair follicles.