Entries by Peter Korytko

Wistars vs Sprague Dawleys – the quest for a perfect strain – new recommendations?

Hi, This week, I spoke with Barry L about the symposium at ACT regarding the use of Wistar rats instead of Sprague Dawleys for new programs. Barry outlined to me that survival is better in Wistars for longer studies. That is good.
Are there any other key info from that symposium that would convince you to use Wistar Hans instead of Sprague Dawleys?
This seems like a great topic for RTC discussion.
Thanks, Peter K. ...


Palladium limits for animal studies

Hi, A client is asking about plladium limits in drug lots for toxicology studies, specifically rats. Do you know of any limits for palladium for toxicology lots? Study duration is short, just 7 days. Palladium content in clinical drug substance is not yet known.
Peter K. ...


N for study

Hi RTC! I have a tiny single dose tolerability study planned to assess local tolerance of formulation in rat. We would evaluate injection site only. I am inclined to use only 5 rats/sex for the main plus additional for recovery with necropsies on Days 3 and 15. What is the minimum number of rats that is acceptable for a local tolerance assessment.  5 seems adequate to me, yet this is lower than a real acute toxicology study. Is there some guidance on number of animals for a local tolerance study? Thanks, Peter