Incidence of hydronephrosis among several production colonies of outbred Sprague-Dawley rats
Van Winkle, T.J.; Womack, J.E.; Barbo, W.D.; Davis, T.W.
Laboratory Animal Science 38(4): 402-406
1988
ISSN/ISBN: 0023-6764 PMID: 3184846 Document Number: 314812
The incidence of hydronephrosis was determined in nine production colonies of Crl:CD (SD) BR rats (CD rats). Kidneys from 3909 rats were examined and 79 (2.0%) had unilateral or bilateral hydronephrosis. A colony with a relatively high incidence of hydronephrosis (4.1%) was chosen for further study. In unselected rats from this colony the incidence in females (87/1882, 4.6%) was not significantly different from that in males (79/1862, 4.2%). In the same group of rats, hydronephrosis was observed most frequently in the right kidney only (2.3%), followed by bilateral involvement (1.2%) and the left kidney only (0.8%). By selection and inbreeding, the incidence of hydronephrosis was increased dramatically (to 33.6%) in two generations. Hydronephrosis in the CD rat appears to be a highly heritable trait, most likely involving more than one gene.