A possible dominant white gene in Jersey cattle

A white heifer ("Snow") was born in 1991 from coloured registered Jersey pa rents. She produced six calves sired by coloured Jersey bulls: three white bull calves, two white heifer calves, and one coloured bull calf. One of th e white bull calves was mated with 40 Hereford x Friesian yearling heifers ( (white face, predominantly black body with some white patches). The 38 re sulting calves included 16 white and 22 coloured calves. Twelve of the 16 w hite calves were heifers and four were bulls. Red or black spotting was rec orded on some white calves. The results are consistent with an autosomal do minant mutant causing the white phenotype. The mutation appears to have ari sen spontaneously in Snow, then passing to her white progeny and white gran d-progeny. The white individuals varied from entirely white in a few cases, to most having some residual small areas of red or black pigmentation in p atterns not typical of other reported white spotting patterns of cattle.