Dantas F P M, Medeiros G X, Figueiredo A P M, Thompson K, Riet-Correa F
Veterinary Hospital, Federal University of Campina Grande, Patos, Paraíba CEP 58700-000, Brazil.
Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
J Comp Pathol. 2014 Feb-Apr;150(2-3):245-52. doi: 10.1016/j.jcpa.2013.11.208. Epub 2013 Dec 3.
This paper reports a newly described form of skeletal dysplasia affecting Brazilian hair sheep of the Cabugi breed. This breed is characterized by having a short head and in some cases the animals are smaller and more compact than sheep of similar breeds. Lambs born with craniofacial abnormalities and dwarfism that die at 2-6 months of age are frequent in this breed. In a flock of 68 ewes and three rams of the Cabugi breed, 134 lambs were born over a 4-year period. Of these, 14 (10.4%) had marked cranial abnormalities and dwarfism and died or were humanely destroyed, 43 (32%) had a normal face and 77 (57.5%) had the short face characteristic of the breed. Dwarf lambs were much smaller than normal, with short legs, a domed head with retruded muzzle and protruded mandible, sternal deformities and exophthalmic eyes situated more laterally in the face than normal. Microscopical examination of long bones of the limbs, bones of the base of the skull and vertebrae showed no lesions. Bones from four affected lambs and one control lamb were macerated for morphometric examination. Although the length of the spinal cord was similar, there was disproportionate shortening of the appendicular bones, particularly the distal segments. Thus the disease was defined as a skeletal dysplasia characterized by craniofacial deformity and disproportionate dwarfism. It is suggested that the disease is inherited as an incomplete dominant trait. The shortened face, which is a feature of the Cabugi breed, may represent the heterozygous state and the more severe, often lethal, dwarfism may occur in homozygotes.
本文报道了一种新描述的骨骼发育不良形式，影响卡布吉品种的巴西毛羊。该品种的特点是头部短小，在某些情况下，这些动物比类似品种的羊更小、更紧凑。在这个品种中，出生时患有颅面异常和侏儒症并在2至6个月龄死亡的羔羊很常见。在一群68只母羊和3只公羊的卡布吉品种中，4年期间共出生了134只羔羊。其中，14只（10.4%）有明显的颅骨异常和侏儒症，死亡或被人道毁灭，43只（32%）面部正常，77只（57.5%）具有该品种特有的短脸特征。侏儒羔羊比正常羔羊小得多，腿短，头部呈圆顶状，口鼻部后缩，下颌突出，胸骨畸形，眼球突出且在面部的位置比正常情况更靠外侧。对四肢长骨、颅底骨和椎骨的显微镜检查未发现病变。对4只患病羔羊和1只对照羔羊的骨骼进行了浸软处理以进行形态测量检查。虽然脊髓长度相似，但附属骨骼，特别是远端节段，出现了不成比例的缩短。因此，该疾病被定义为一种以颅面畸形和不成比例的侏儒症为特征的骨骼发育不良。有人认为该疾病作为一种不完全显性性状遗传。卡布吉品种特有的短脸可能代表杂合状态，而更严重的、通常致命的侏儒症可能发生在纯合子中。
