Skip to main content
padlock icon - secure page this page is secure

Open Access A Simple and Reliable Method for Early Pregnancy Detection in Inbred Mice

Download Article:
 Download
(PDF 148.8 kb)
 
The study of normal and abnormal development typically requires precise embryonic staging. In mice, this task is accomplished through timed matings and the detection of a copulation plug. However, the presence of a plug is not a definitive indicator of true pregnancy, particularly in inbred mice, in which false-pregnancy rates have been reported to be 50% or higher, depending on the strain. This high rate poses considerable financial and animal use burdens because manipulation of the putative dam is often required before pregnancy can be confirmed by palpation or visual inspection. To address this problem, we examined weight gain in a population of 275 wildtype C57BL/6J mice (age, 12 wk or older) between the time of plug detection and during early embryogenesis (gestational days 7 to 10). In this population, assessing pregnancy according to the presence of a plug alone yielded a 37.1% false-positive rate. Pregnant mice gained an average of 3.49 g, whereas non-pregnant mice gained only 1.15 g. Beginning at gestational day 7.75, implementing an optimal weight-gain discrimination threshold of 1.75 g reduced the false-positive rate to 10.5%, without excluding any pregnant mice. These results were consistent with those from younger (age, 8 wk) wildtype C57BL/6J and FVB/NTac female mice, suggesting broad applicability of this method across age and strain. Our findings provide a simple and effective method for reducing animal use and study costs.

10 References.

No Supplementary Data.
No Article Media
No Metrics

Document Type: Research Article

Affiliations: 1: Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA 2: Research Animal Resource Center, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA 3: Research Animal Resource Center, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA 4: Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, Wisconsin, USA. [email protected]

Publication date: July 1, 2015

More about this publication?
  • The Journal of the American Association for Laboratory Animal Science (JAALAS) serves as an official communication vehicle for the American Association for Laboratory Animal Science (AALAS). The journal includes a section of refereed articles and a section of AALAS association news. The mission of the refereed section of the journal is to disseminate high-quality, peer-reviewed information on animal biology, technology, facility operations, management, and compliance as relevant to the AALAS membership. JAALAS accepts research reports (data-based) or scholarly reports (literature-based), with the caveat that all articles, including solicited manuscripts, must include appropriate references and must undergo peer review.

    Attention Members: To access the full text of the articles, be sure you are logged in to the AALAS website.

    Attention: please note, due to a temporary technical problem, reference linking within the content is not available at this time

  • Editorial Board
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Membership Information
  • Information for Advertisers
  • For issues prior to 1997
  • Institutional Subscription Activation
  • Ingenta Connect is not responsible for the content or availability of external websites
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more