Perosomus elumbis in piglets: Pathological, radiological and cytogenetic findings

Perosomus elumbis (PE) is a rare congenital condition characterized by agenesis of the lumbar, sacral and coccygeal vertebrae. Perosomus elumbis has rarely been reported in literature as morphological description of singles or few cases. Here we report the first extensive description of eight cases of PE detected in two consecutive litters from the same parents of Casertana pig breed. In August 2018, eight piglets were investigated for multiple malformations. All malformed animals, but one, died in the first day of life. The survivor piglet died at 23 days of age. Pathological, radiological and cytogenetic examination was performed. Furthermore, a farm epidemiological investigation was carried out to investigate the percentage of piglets born dead or with malformations in 2018. The radiological and pathological exams showed skeletal abnormalities at the spinal cord level and visceral malformations. Cytogenetic investigations showed a normal chromosome arrangement. Finally, epidemiological investigation revealed a low prevalence of malformations in newborn pigs, equal to 0.5% of the total birth rate of the farm. Our findings report the first extensive description of PE cases in pigs and suggest an underestimation of this malformation in veterinary medicine. Our findings also suggest a specific genetic etiological basis as cause of PE in pigs and exclude chromosomal abnormalities. Further studies will be performed to confirm this hypothesis.