Abdominal Ectopic Pregnancy and Impaired Postnatal Mammary Gland Development, Consistent With Physiologic Agalactia, in a Wild European Rabbit, Oryctolagus cuniculus

Abstract

A wild European rabbit, Oryctolagus cuniculus , was diagnosed with an abdominal pregnancy due to the presence of a single abdominal lithopedion attached by a thin fibrovascular stalk to the left uterine horn, which was distorted by the tension of the adhesion. Evidence of mineralized remnants, chronic inflammation, and fibrosis in the left uterine endometrium and myometrium suggested that the lithopedion had arisen as a secondary abdominal pregnancy. The right uterine horn contained two macroscopically normal fetuses. The mammary gland exhibited notably retarded development in relation to the size of the fetuses. Histologically, mammary alveoli lacked evidence of intraluminal secretory product, and ducts lacked prominence and contained clusters of small numbers of macrophages. The doe also exhibited mild granulomatous and heterophilic pneumonia with rare intralesional adiaspores, suggesting infection with Emmonsia spp. as an incidental finding. This case documents secondary abdominal pregnancy in a wild lagomorph not subjected to artificial insemination procedures suggested to increase the occurrence of this condition in farmed rabbits. An abdominal pregnancy is one of a number of factors that should be considered as a potential factor in the etiology of impaired postnatal mammary development or reduced milk yield in a breeding doe, although no causative association is demonstrated in this case. Abdominal ectopic pregnancy is one possible differential diagnosis in the investigation of the presence of a palpable abdominal mass or masses in O. cuniculus .

Development and Pathology of the Equine Mammary Gland

“…By contrast, true agalactia reflects persistent lack of lactation with a variety of potential underlying aetiologies which may pertain either directly to the patient or to the patient's environment [94]. In addition to small domestic carnivores, agalactia has been described in diverse species including pigs [95,96], rabbits [97,98], and horses [99,100].…”

Renal pathology in wild European rabbits

“…This rabbit also had a high burden of pulmonary adiaspores, which we have previously recognised in other wild rabbits. 11,22 Our data, examining a small local population of wild rabbits, demonstrate that renal pathology is not highly prevalent in this group of animals. Further studies are required to determine whether this is also the case for the wider UK wild rabbit population.…”

Ectopic Pregnancy Diagnosed Post Caesarean Surgery in a Three Year Old Boerboel Bitch

“…Ectopic pregnancy has been reported in rabbits [4], cats [3] and dogs [9]. Four main types of extrauterine pregnancy based on location have been reported in human and other animals with various subtypes.…”

“…It is the most common type of ectopic pregnancy in humans, but is rarely found in domestic animals because of the different physiology of the DOI: 10.2478/fv-2021-0032 uterus between humans and animals. Abdominal ectopic pregnancy is the most common type of ectopic pregnancy in animals, including bitches [4]. An abdominal ectopic pregnancy occurs when the foetus is implanted or existed in the abdominal cavity [2].…”

“…An abdominal ectopic pregnancy can also be described as primary or secondary. Primary abdominal ectopic pregnancies occur as a result of entering and the implantation of a fertilized egg forming a placental relationship on the peritoneal or omental surface through the oviductal fimbria [4]. The placental attachment in the primary form may also be on the mesentery, liver, spleen and the large and small intestines [2].…”