Hypoplasia of ribs associated with cleft palate, cleft lip, and unilateral renal agenesis in a neonate dog of undefined breed

Abstract

Congenital defects can cause changes in the normal function or morphology of organs, thus contributing to neonatal mortality. Malformations in dogs occur as a result of genetic factors or by the action of teratogenic agents during pregnancy. Genetic defects can be inherited from one or both parents. These defects are more common in purebred puppies or can even be the result of consanguinity. Teratogenic agents, such as toxins, drugs, infectious diseases, mechanical influences, and irradiation, may affect the litters during gestational development. Hypoplasia of ribs has been described in human newborns. It is a rare and lethal malformation of autosomal recessive inheritance that prevents thoracic expansion and reduces pulmonary compliance, causing respiratory failure. A pregnant bitch of undefined breed was submitted to caesarean section. At birth, a neonate exhibited respiratory distress, and the palpation of the thorax indicated absence of ribs. In addition, the newborn had cleft palate and cleft lip, which led to perform the euthanasia of the animal. Post-mortem examination indicated hypoplasia of ribs and unilateral renal agenesis. As in the canine neonate, hypoplasia of ribs in human newborns is also associated with other malformations, such as cleft lip, cleft palate, and urogenital defects. The present report describes the first case of hypoplasia of ribs associated with other malformations in a canine neonate, the cause being possibly related to a genetic hereditary factor.