Eyster G E, Evans A T, Blanchard G L, Krahwinkel D J, Chaffee A, DeYoung D, Karr D R, O'Handley P
J Am Vet Med Assoc. 1977 Mar 1;170(5):516-20.
Four Collie littermates had multiple cardiac and diaphragmatic anomalies. Ventricular septal defect was found in 3, pulmonic stenosis in 2, atrial septal defect in 1, mitral regurgitaion in 1, and pericardial diaphragmatic hernia in 3. Five additional littermates died within 72 hours of birth but were not necropsied. On the basis of available evidence, it was believed that the defects were congenital but not hereditary.
四只柯利犬同窝幼犬患有多种心脏和膈肌异常。3只发现室间隔缺损，2只发现肺动脉狭窄，1只发现房间隔缺损，1只发现二尖瓣反流，3只发现心包膈疝。另外5只同窝幼犬在出生后72小时内死亡，但未进行尸检。根据现有证据，认为这些缺陷是先天性的而非遗传性的。
