I don't know much about this condition, but I did find this reference under
“Croiteach” in my Endnote files.
Nisbet, D. I., Butler, E. J., Robertson, J. M. and Bannatyne, C. C. 1970.
Osteodystrophic diseases in sheep. IV: Osteomalacia and osteoporosis in
lactating ewes on West Scotland hill farms. Journal of Comparative Pathology
I hope it helps.