Because of the very small parental population in Japan and even smaller population of Wagyu cattle exported from Japan, its population outside Japan is based on just a few founder animals. This results in numerous, recessive genetic defects in this race. Tests presented below can help with breeding planning and disease prevention.
Band 3 (deficit of red blood cell membrane protein III):
The affected calves suffer from anaemia, low body weight and general weakness, often dying during the first weeks.
CHS (Chediaka-Higashi syndrome):
These animals are characterised by weaker protection against bacterial infections. This disease is not always lethal.
F11 (factor XI deficit):
These animals suffer from bleeding occurring upon injury and during some procedures, e.g. during horn removal or castration. Problems with fertilization and pregnancy are also prevalent.
CL16 (claudin 16 deficit):
This disease affects several internal organs, in particular kidneys. Although the affected animals can live, their lifespan is shorter and they may die because of kidney failure. Moreover, these animals grow slower and display increased hoof growth.