Scheider A, Schmidt P, Distl O
Institut für Tierzucht, Ludwig-Maximilians-Universität München.
Berl Munch Tierarztl Wochenschr. 1994 Oct;107(10):348-52.
The present study describes an anomaly of the pinna of the ear and its distribution in Highland Cattle. The investigation is based on a questionnaire survey in farms in Bavaria keeping robust breeds and on registering data in 15 selected farms. In the year 1991, there were registered 548 Highland stud book cows in 108 farms. In four herds animals of the breed Highland Cattle were observed which showed crop ears. Always both ears were affected and this ear defect could be already observed in newborn calves. Crop ears appeared in very different forms. In some cases only small changes of the external ear could be recognized, in more severe cases, grooves in the external ear could be found and in the most severe case, the external ear was totally deformed and drastically reduced in size. In one herd, 45 animals out of the progeny of 46 of one affected breeding bull showed crop ears. The pedigrees indicated that this defect of the ear pinna is inherited and a single autosomal gene with nearly additive (incomplete dominant) action may be involved. Homozygote recessive animals are free from crop ears, animals homozygote for the mutated allele carry totally deformed external ears and heterozygote animals do not show as severe forms of crop ears as homozygote ones.
本研究描述了高地牛耳廓异常及其分布情况。该调查基于对巴伐利亚饲养强壮品种的农场进行的问卷调查，并在15个选定农场记录数据。1991年，108个农场登记了548头高地种牛登记簿上的母牛。在四个牛群中观察到高地牛品种的动物出现了卷耳。总是双耳都受影响，这种耳部缺陷在新生犊牛中就已能观察到。卷耳呈现出非常不同的形式。在某些情况下，只能识别出外耳的微小变化；在更严重的情况下，外耳会出现凹槽；在最严重的情况下，外耳完全变形且尺寸大幅减小。在一个牛群中，一头受影响的种公牛的46头后代中有45头出现了卷耳。系谱表明，这种耳廓缺陷是可遗传的，可能涉及一个具有近乎加性（不完全显性）作用的单常染色体基因。纯合隐性动物没有卷耳，突变等位基因的纯合动物携带完全变形的外耳，杂合动物的卷耳形式不像纯合动物那么严重。
