Severe Bilateral Microphthalmia in a Holstein Calf

This report described a severe bilateral microphthalmia in a young Holstein calf. The anomalous calf with wry tail showed normal vigor, appetite and normal body weight except for eye defect. The orbits were shallower and smaller than normal. The orbit bilaterally contained a white small mass suspected as eyeball. A spot-like remnant of eyeball (REB) was buried in the mixture of vestigial extraocular muscles and adipose tissue of the bilateral orbit. Histologically, the REB was composed of irregularly arranged elements of ocular wall such as sclera, retina and ciliary body. But any destructive changes in the central nervous systems were not detected. This case of eye defect was defined as severe bilateral microphthalmia. The cause of this ocular defect is unknown.