Updated Mar 02, 2021 | 13:11 IST Even though she was quickly rescued, one of her eyes had to be removed because it was infected. Over-breeding leaves horse with vitiligo, mistaken as cow Over-breeding of a horse in the UK's Essex has lead to some shocking results that left rescuers confused. Minstral the horse, who has white patches on her body, made rescuers think she is a cow. She has developed a skin condition called vitiligo, which experts believe is because of over-breeding. Vitiligo is a long-term skin condition that is characterised by white and off-coloured patches on the skin losing their pigment. The affected areas become white with sharp margins.