Congenital Caudal Vertebral Anomalies in a Pedigree of Beagles

Despite increased recognition of caudal vertebral anomalies in the domestic dog (Canis lupus familiaris), studies describing tail deformities remain limited. To address this gap in the literature, this study aimed to identify and classify the caudal vertebral anomaly phenotypes in a pedigree of Beagles. Subjects included 67 dogs (36 males and 31 females), aged eight months to eight years old (M= 38.8 ± 25.6 months). All 67 dogs were visually examined, and tails were palpated to determine if they had any kinks, bends, misalignments, or deformities in their tail prior to radiographic assessment. Radiographs of the caudal vertebrae were obtained from 53 dogs and evaluated for congenital anomalies, including block vertebrae, hemivertebrae, brachyury (very short tail), and axial deviations. Of the 53 radiographed dogs, 25 (47.2%) exhibited at least one congenital caudal vertebral anomaly, with block vertebrae being the most common finding (43.4%). Four dogs (7.6%) had mild congenital abnormalities detected radiographically that were not identified during physical examination. Based on pedigree structure, an autosomal recessive trait is suspected. These findings demonstrate a high prevalence of caudal vertebral anomalies within this pedigree of Beagles and emphasize the importance of radiographic evaluation for accurate identification and phenotypic classification.