Multifactorial inheritance of Halo-hair abundance in New Zealand Romney sheep.

Abstract

Halo-hair abundance is strongly inherited in sheep less than N-grade. The tabulated breeding results have the appearance of typical multifactorial inheritance. Lambs without halo-hairs on the back probably vary in the genetic margin by which they have escaped growing halo-hairs there. Further work is desirable on the inheritance of great freedom from halohairs on the extremities, especially the britch, and its significance for fleece characterization. Either one or two many-halo rams (not N-grade) bred from, which did not sire any N-grade lambs, may have been N /+. The same problem of poor expressivity is posed by many-halo rams judged N /+ that sired very few N-grade lambs. Further breeding experiments are called for, both with sheep less than N-grade known to be N /+ and their descendants, and with many-halo sheep from Romney flocks.