Abdominal pregnancies in farm rabbits.

Abdominal pregnancy is defined as the implantation and development of a fertilized ovum or a embryo in the peritoneal cavity. Although this has been reported in several species, it is considered as a low incidence process. It is classified as a primary abdominal pregnancy, if there is no evidence of uterine rupture, with presumed regurgitation of early embryos from the uterine tube and as a secondary abdominal pregnancy, when there is evidence of uterine rupture. During a necropsy study of 550 adult fertile female New Zealand white rabbits (Oryctolagus cuniculus) from two rabbit farms in Valencia (Spain), the main causes of elimination were studied. Twenty-eight abdominal pregnancies were diagnosed. Seven animals showed no lesions in their reproductive tract. The remaining twenty one animals showed acute or chronic lesions in the reproductive tract. The classification as a primary or secondary condition is discussed. It may be concluded therefore that extrauterine pregnancies would not be such an unusual finding in rabbits, and that this premise should be considered in the diagnostic approach when assessing rabbit doe pathology. New husbandry systems in rabbits such as artificial insemination are factors to be considered.