Magdesian K Gary, Williams D Colette, Aleman Monica, Lecouteur Richard A, Madigan John E
Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA.
J Am Vet Med Assoc. 2009 Nov 15;235(10):1204-11. doi: 10.2460/javma.235.10.1204.
To evaluate deafness in American Paint Horses by phenotype, clinical findings, brainstem auditory-evoked responses (BAERs), and endothelin B receptor (EDNBR) genotype.
Case series and case-control studies.
14 deaf American Paint Horses, 20 suspected-deaf American Paint Horses, and 13 nondeaf American Paint Horses and Pintos.
Horses were categorized on the basis of coat color pattern and eye color. Testing for the EDNBR gene mutation (associated with overo lethal white foal syndrome) and BAERs was performed. Additional clinical findings were obtained from medical records.
All 14 deaf horses had loss of all BAER waveforms consistent with complete deafness. Most horses had the splashed white or splashed white-frame blend coat pattern. Other patterns included frame overo and tovero. All of the deaf horses had extensive head and limb white markings, although the amount of white on the neck and trunk varied widely. All horses had at least 1 partially heterochromic iris, and most had 2 blue eyes. Ninety-one percent (31/34) of deaf and suspected-deaf horses had the EDNBR gene mutation. Deaf and suspected-deaf horses were used successfully for various performance events. All nondeaf horses had unremarkable BAER results.
Veterinarians should be aware of deafness among American Paint Horses, particularly those with a splashed white or frame overo coat color pattern, blend of these patterns, or tovero pattern. Horses with extensive head and limb markings and those with blue eyes appeared to be at particular risk.
通过表型、临床检查结果、脑干听觉诱发电位（BAER）和内皮素B受体（EDNBR）基因型评估美国花马的耳聋情况。
病例系列研究和病例对照研究。
14匹耳聋的美国花马、20匹疑似耳聋的美国花马以及13匹听力正常的美国花马和花斑马。
根据毛色图案和眼睛颜色对马匹进行分类。检测EDNBR基因突变（与奥洛致死白驹综合征相关）并进行BAER检测。从病历中获取其他临床检查结果。
所有14匹耳聋马匹的所有BAER波形均消失，符合完全耳聋的表现。大多数马匹具有溅白或溅白 - 框架混合毛色图案。其他图案包括框架型奥洛和托沃罗。所有耳聋马匹头部和四肢均有广泛的白色斑纹，尽管颈部和躯干的白色量差异很大。所有马匹至少有1只部分异色虹膜，大多数有2只蓝色眼睛。91%（31/34）的耳聋和疑似耳聋马匹存在EDNBR基因突变。耳聋和疑似耳聋的马匹成功用于各种表演赛事。所有听力正常的马匹BAER结果均无异常。
兽医应注意美国花马中的耳聋情况，特别是那些具有溅白或框架型奥洛毛色图案、这些图案的混合或托沃罗图案的马匹。头部和四肢有广泛斑纹以及有蓝色眼睛的马匹似乎风险尤其高。
