Bos taurus breeds are descendants of the ancient Celtic Shorthorn. Bos taurus breeds show a closer resemblance to the Aurochs, particularly Scotch Highland cattle, than Bos indicus breeds. Bos taurus can be classified into two sub-categories, British breeds and Continental breeds. Continental breeds, also called Exotics, are breeds that originated in Europe. These cattle are known for weight gain and cutability. Continental breeds are generally large in size, lean, muscular, and vary in adaptability to hot climates. The following Continental breeds are commonly found in the United States.
The Charolais breed was developed in France and was introduced into the United States in 1936. This breed ranges from white to light straw in color. Charolais cattle can be horned or polled. This large, heavily muscled breed’s traits include a fast growth rate and feed efficiency.
Complete albinism was reported from two purebred Charolais herds. The first calf brought to us was a 2-week-old purebred bull Charolais calf, and it was presented to us because of blindness. Six such blind calves were seen over a 5 year period in this purebred Kansas Charolais herd. They were sired by the same bull and all 5 dams were half sisters. One dam had an albino calf in successive years. After removal of the bull no more cases of albinism were observed. Bull and all dams involved had normal eye color. A 5-week-old male purebred Charolais calf from a 50 head purebred cow Charolais herd in Missouri was presented to us in lateral recumbency. It had opisthotonus, nystagmus, and appeared to be blind. The owner had not encountered any other animal with pigmentary anomalies previously. The animal was euthanatized and necropsied.
Albinism appears to be a rare defect. In Swiss Brown cattle in Switzerland, the recessive gene was estimated to house a frequency of 0.002 I( NZENWRIED & A-LU V,ERGNE 1970). In a US survey of bovine birth defects involving over 70,000 births, no albinos were encountered, making the frequency of the albino gene, if recessive, to be less than 0.004 E( IPLOLD et al., 1972). R GEENE et al. (1973) concluded that the type of inheritance of albinism in Beef Shorthorns appeared to be recessive. The pattern of occurrence of albinism in these two purebred Charolais herds is suggestive of a recessive mode of inheritance. However, further investigations are warranted to elucidate the exact nature of inheritance of complete albinism among Charolais cattle.