A 7-year-old African wild dog (Lycaon pictus) multiparous bitch, which previously had delivered without complication (more than seven pups at a time), began parturition late on 16 November 2005. The next morning, she had delivered three live pups and lay recumbent, straining. The bitch continued to experience dystocia throughout the day and died that night.
Necropsy revealed three placental attachments in the right uterine horn and one in the left. A full-thickness rupture of the right horn at the middle placental attachment and an autolyzed fetus, lying free in the abdomen, were present. Myometrium adjacent to the rupture was subdivided into irregular pseudolobules by fibrous connective tissue tracts and rare, small endometrial glandular acini. Small islands of endometrial glands and surrounding stroma extending deep into the myometrium occurred in the left uterine horn, in some places close to the serosa (adenomyosis). Death was attributed to hypovolemic and endotoxemic shock after intrapartum uterine rupture.
Uterine rupture has been reported in domestic canids2,4 and is precipitated by events like periparturient trauma, uterine wall alterations, uterine torsion, or inappropriate manual or chemical treatment.5 In this case, the small litter may have resulted in abnormally large and unevenly distributed pups,2,3 facilitating birth canal obstruction, increased uterine contractions and uterine rupture.2 Adenomyosis of the uterine wall may have provided less resistance to contractions. The cause of adenomyosis is unknown, although prolonged estrogen stimulation is postulated.1 To our knowledge, this is the first report of both adenomyosis and uterine rupture in a wild canid.
The authors would like to thank the staff of the De Wildt Cheetah and Wildlife Center, and the laboratory staff at the Pathology Section, Faculty of Veterinary Science, University of Pretoria.
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