Case Report: Integrated imaging and molecular diagnostic approach to congenital hip dysplasia in a Hanwoo calf.

Congenital musculoskeletal disorders in calves, including those of genetic, infectious, or nutritional origin, can result in significant economic losses because of lameness, increased treatment costs, and reduced productivity. However, an accurate diagnosis is often difficult under field conditions. This report presents a case of bilateral hip dysplasia in a 1-month-old Hanwoo calf born prematurely that exhibited progressive lameness and joint deformities. Radiographic and computed tomography examinations revealed shallow acetabular sockets and underdeveloped femoral heads, consistent with congenital hip dysplasia. Additional abnormalities were observed in the left talus and calcaneus. Hematological and biochemical analyses results were unremarkable. Polymerase chain reaction assays for commonly implicated congenital viral pathogens yielded negative results; therefore, the underlying etiology was suspected to arise from genetic defects. The calf's clinical condition deteriorated over time, and cessation of treatment was decided. Necropsy confirmed severe bilateral joint dysplasia, luxation, and femoral head erosion. This is the first documented case of bilateral hip dysplasia in a Hanwoo calf confirmed by advanced imaging and necropsy. This report emphasizes the diagnostic value and clinical significance of advanced diagnostic modalities in assessing comparable defects in Hanwoo cattle.