f6098d8b__and_Use_of_Laboratory_Animals__Comments
[ID] 316 [Entry Date] 04/21/2011 at 07:41:57 AM [Affiliation] Self [Comments] 
Comment 1: April 12, 2011 To Whom It May Concern, I am quite concerned about the mouse breeder cage occupancy guidelines as proposed in the most recent Guide for the Care and Use of Laboratory Animals. The 51 in2 requirement for a single female with a litter would make monogamous pairing the only possible housing arrangement for the standard mouse cage (81 in2). This will dramatically increase the cost of maintaining mice and is counter to what is reported in the scientific literature on the effects of housing density on mouse biological parameters. Peters A, Festing M. Population density and growth rate in laboratory mice. 1990. Lab Anim 24:273-279. Smith AL, Mabus SL, Stockwell JD, Muir C. Effects of housing density and cage floor space on C57BL/6J mice. 2004. Comp Med 54:656-663. Smith AL, Mabus, SL, Muir C, Woo Y. Effects of housing density and cage floor space on three strains of young adult inbred mice. 2005. Comp Med 55: 368-376. Davidson LPO, Chedester AL, Cole MN. Effects of cage density on behavior in young adult mice. 2007. Comp Med 57:355-359. Laber K. Veatch LM, Lopez MF, Mulligan JK, Lathers DM. Effects of housing density on weight gain, immune function, behavior and plasma corticosterone concerntrations in BALB/c and C57BL/6 mice. 2008. J Am Assoc Lab Anim Sci 47:16-23. In addition, the guidelines go beyond the European guidelines as outlined in the Council of European Convention which is counter to attempts to harmonize guidelines between different geographic regions.. For most academic institutions in the United States the options are to house breeding mice in monogamous pairs or purchase all new caging. One of the problems with housing mice in monogamous pairs is that there is less social interaction between mice, and it is my experience based upon work with rodents for over 25 years that mice breed better in a social setting. In short, the specific requirement to house a female male with a litter at 51 in is a bad standard and should be changed to be more consistent with European standards (a single male and two females in a standard sized mouse cage). Respectfully Submitted, ***** Comment 2: recommend implementation one year after OLAW acceptance.
Listing of Public Comments on Proposed Adoption and Implementation of the Eighth Edition of the Guide for the Care and Use of Laboratory Animals