These are called Albino Animal.
Albinism is a form of hypopigmentary congenital disorder, characterized by a partial (in hypomelanism, also known as hypomelanosis) or total (amelanism or amelanosis) lack of melanin pigment in the eyes, skin and hair (or more rarely the eyes alone). Albinism results from inheritance of recessive alleles.
Splendid Albino Animal - The Rarity of The Moment