Amelia di un arto anteriore in un puledro trottatore Italiano

Amelia is a malformation characterized by the absence of limbs. It is an ectromelia, a congenital total or partial absence of one or more limbs. Although the true prevalence could be underestimated, very few cases are described in horses since the affected foals are routinely euthanatized. In the current study, a case of amelia of the right forelimb in a Standardbred foal is reported. Clinical evaluation revealed the absence of the right forelimb and showed that no other clinical defects were present. The foal was euthanatized, as requested by the owner. Radiological assays and necropsy confirmed the clinical findings. Hereditability of limb congenital deformities have been demonstrated in many species, and the genes involved have been identified. Environmental factors, such as toxic agents with a mutagenic effect (e.g. dioxins, thalidomide) during the earlier ontogenetic stages, can lead to chromosome instability and mutations and be responsible for different malformations. Based on the knowledge of the parental siblings and the reported cases of ectromelia in ewes from the same geographical area induced by toxic effects of dioxins, the current study speculates a teratogenic etiology. To the Authors' knowledge, this is the first case reported in the Standarbred.