Oculocutaneous hypopigmentation of Angus cattle

Abstract

Congenital defects are abnomalities of structure or function present at birth. They may affect only a single anatomical structure such as the eye, an entire system, parts of several systems or involve several body systems, or combine functional and structural defects (syndrome). Many different congenital defects, either of genetic, environmental, or unknown cause, or due to environmentalgenetic interaction have been identified in cattle and other food producing animals and many more undoubtedly exist. Defects range from blemish to severe anomalies and may be manifested by embryonic mortality, fetal death, mummification, abortion, dysmaturity, premature birth, fullterm stillbirth, or nonviable or viable neonate. With increasing use of modern technology such as artificial insemination and embryo transfer in domestic animals, defects no longer are rare; all are important.

The majority of studies of pigmentation defects have taken place in the mouse. Since it is easy to handle, has low maintenance cost, and can produce a large number of generations in a short period of time, it is particularly suited for this research. Studies involving cattle necessarily take more time and money. This paper presents clinical, clinipathologic, gross, microscopic and electron microscopic studies of oculocutaneous hypopigmentation in Angus cattle.