Basic Mouse Care Question - (Feb/16/2007 )

Sorry if this seems like a very basic question, but why is it always written that mice are given access to food and acidified tap water ad libitum? My main question here is why is the water acidified? Does it have to do with reducing contamination? Is it better for the mice somehow? A web search turned up no clues just tons of examples of people putting that line in their publications. So, why is mice water always acidified? I know sometimes we add tetracycline to the water for tetracycline on/off controlled genes but this is stated in papers and on water bottles for mice that don't use the tetracycline gene control system as well. What pH is used or how is the water acidified (add acetic acid or HCl or something)?

Thanks for any help, sorry if this is real basic but I've never been involved in the actual care of mice (just kill them for my experiments).

Well, we give our mice normal drinking water and its not acidified. As far as I know, drinking water by human standards that what they got. We would get the water directly from the tap for the mice.

I dont now abt the water having to be acidified.

According to JAX, it is to prevent microbial growth, as I suspected.

"Thank you for your inquiry.

The acidified water is used to prevent the growth of microorganisms.
Here
is the description of the watering system in our production facility.

Water - Water bottles (drilled-hole type) are purchased from Thoren
Caging
Systems, Inc. We do not maintain an automated watering system. Water
from
the public Bar Harbor, Maine water system is filtered (15-20 microns).
A
compound with vitamin K activity (menadone sodium bisulfate, MSB) is
added
at a rate of 0.4 mg MSB per ml of water (not done at JAX® West). MSB
was
initially added to compensate for a decrease in vitamin K activity in
diets
subjected to autoclaving. We now purchase autoclave-stable diets, but
continue to add the MSB until further testing is done. JAX® West
drinking
water is supplied from a local source and so may differ in mineral
content
from that used in Bar Harbor, Maine. Water in both facilities is
acidified
with HCl to achieve a pH of 2.8-3.1, primarily to control Pseudomonas
sp.

I hope that you will find the information helpful. Please feel free to
contact us again if you have questions."