title: Observations on parturition in the sow. II. Factors influencing stillbirth and perinatal mortality.
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001722:Birth Order; D005260:Female; D005313:Fetal Death / Q000209:etiology / Q000662:veterinary*; D007746:Labor Presentation; D007743:Labor, Obstetric; D011187:Posture; D011247:Pregnancy; D013552:Swine; D013553:Swine Diseases / Q000401:mortality*; D013997:Time Factors; D014470:Umbilical Cord