Polled livestock

Polled livestock (or pollards) are livestock of normally-horned species that are lacking horns, either naturally or as a result of humans removing them or preventing their growth.

Prevention of horn growth is most commonly done by "dehorning" or "disbudding" – burning out the horn buds of a young animal, sometimes under local anaesthetic. before the horns have grown.

Some livestock are "naturally polled" due to a gene which suppresses horn development. These include many cattle breeds, including Angus and Galloway, and some sheep breeds, including Suffolk sheep; in some other sheep breeds, such are Merino, only the females are polled.

Natural polling also occurs in goats, but development of wholly polled strains is possible, as the polled trait is not created by a single mutation, but is part of a Polled Intersex Syndrome. If two polled goats are mated the offspring are often infertile.

In cattle, the polled gene is genetically dominant. Naturally polled breeds have been used to produce polled strains of normally horned breeds.

Polled animals occasionally have "scurs" – small, loose horny growths in the skin where their horns would be. In cattle this trait has traced to an allele of different gene, on a different chromosome, than the gene responsible for polled cattle. However the presence of the allele for scurs can only be seen in a polled animal, because the animal has to be polled to see the scurs. . [cite journal
last = Long | first = C. R.
title=Inheritance of the horned, scurred, and polled condition in cattle
journal=Journal of Heredity
year=1978 | volume=69 | pages=395–400 ]

Polled livestock are preferred by many farmers for a variety of reasons, the foremost being that horns can pose a physical danger – to humans, other livestock and equipment. Horns may also interfere with equipment used with livestock (such as a cattle crush), or they may become damaged during handling.

In other circumstances horned animals may be preferred, for example to help the animal defend itself against predators, to allow the attachment of head yokes to draught oxen, to provide a hand-hold on smaller animals such as sheep, or for aesthetic reasons – for example in some breeds the retention of horns is required for showing.

ee also

* Livestock dehorning

=References=