Alopecia areata in two black Angus cows

Area of Science:

• Veterinary Dermatology
• Animal Pathology

Background:

• Alopecia areata is an autoimmune condition affecting hair follicles.
• This condition is rarely reported in cattle, with limited histopathological data.

Observation:

• Progressive alopecia and leukotrichia were observed in two adult (6 and 7 years old) registered Black Angus cows.
• Clinical signs included hair loss and whitening of the hair coat.

Findings:

• Histopathology revealed melanin clumping, matrix cell degeneration, and giant multinucleate cells within hair bulbs.
• Peribulbar melanin incontinence, fibrosis, and dystrophic hair shafts were noted.
• Intrabulbar and peribulbar lymphocytes were identified as cluster of differentiation (CD)3-positive T cells.

Implications:

• These findings suggest a T-cell mediated autoimmune process similar to human alopecia areata.
• This case report expands the understanding of alopecia areata in cattle.
• Further research into the pathogenesis and potential genetic factors is warranted.