Currently all colonies are at Charles River Laboratories. Please note that animals in different contracts must be ordered on separate order forms:
All rats in the aging colony are under contract 11 02i
All mice in the aging colony are under contract 10 06i
All caloric restricted mice and the ad lib fed controls for the caloric restricted mice are under contract 12 01i
Notice: change in source of F344 foundation stock
For all previous new F344 colony development, the NIA used foundation stock from the NIH Animal Genetic Resource. This facility was closed around 2004. Unfortunately, the F344 breeding stock from the NIH colony that was sent to the Rat Resource and Research Center would not breed, so this source of F344 stock is lost to us. The last stock we received from the NIH, for the caloric restriction colony, also bred poorly, suggesting an unknown genetic change in the NIH foundation stock. To ensure that we used foundation stock from a source that would likely be available for the long-term and for which the breeding patterns were consistent with F344’s history, we chose the Charles River-derived Fisher rat, F344-cdf. The description of the F344-cdf can be found at http://www.criver.com/en-US/ProdServ/ByType/ResModOver/ResMod/Pages/CDF.aspx  .
Before making this decision, we had a genetic comparison done between the F344-nih (n = 18) and F344-cdf (n = 12). On a panel of 106 SNPs spanning all chromosomes, 100 of them were identical between the two colonies (94.3% identity):
While we cannot be sure how the change in the foundation stock will affect aging phenotypes, we feel that this is the best long-term solution to the loss of the NIH foundation stock. We are developing colonies of F344-nih (using breeding stock from our caloric restricted colony started in 2004) and F344-cdf in parallel so that investigators can compare the two substrains in their assays. Entries of the F344-nih began in the spring of 2013 and will be phased out by the end of 2014 so aged F344-nih will only be available until the end of 2016. Investigators wishing to make such comparisons should plan accordingly. In the beginning, F344-nih will be the default strain shipped unless the order states a specific request; by around 2015, it will switch to F344-cdf being the default strain.
The first cohorts of F344-cdf will be set aside for a lifespan study and the results of that study will be posted here as they become available. If anyone wants to share data comparing F344-cdf to F344-nih, we would be happy to post it here with appropriate citation. To submit comparison data, contact Dr. Nancy Nadon, firstname.lastname@example.org .
** The new rat colony is at Charles River Laboratories (CRL). Because of delays in the development of the F344 breeding colony, the Brown Norway (BN) rats will transition to the new colony at CRL before the F344 rats transition. BN rats with dates of birth (DOB) through 10/12 will be shipped from Harlan, those with DOBs after 10/12 will be shipped from CRL and must be on separate orders from the older BN rats. Hybrid rats with DOB through 5/13 will ship from Harlan until the transfer, and DOBs of 6/13 and after ship from CRL. Up-to-date instructions will be provided on the strain ordering pages of the online rodent ordering system.
Please note, at the end of the Harlan (hybrid and BN rats) and Taconic (F344) contracts, the rats remaining will be transferred to CRL (dates not yet determined). During the period when the older rats are still at Taconic or Harlan, orders for young and old rats from different contracts must be placed separately. After the rats are transferred to CRL, orders for old and young rats can be submitted on the same order. Please pay close attention to the instructions on the individual strain ordering pages of the online order form.