
I learned Anseptic technique on Friday (curses for not posting it then; I'd have had a post on 08.08.08!), which is very useful. Apparently it's a major skill.
I'll tell you why; on Friday, I went to see the Microbiologist. We went up to the maintenance area and took water samples - raw water is brought in, softened with calcium, filtered and run under UV light to kill off bacteria. The maintenance system is complex - certain "clean" animal units are ventilated to have positive pressures so any pathogens are blown away from the doors.
Anyway, the taps are swabbed with a 70% ethanol mix and then allowed to run for a bit (in case any water is standing in the pipe - that skews how many bugs show up). The water sample is then taken back, and diluted three fold (this facilitates colony counting). You drop samples with a pasteur pipette - it's a special pipette that drops 1/5th of a millilitre per drop -
onto an agar plate (which sometimes has sheep's blood in it, depending on what you're trying to culture). The plates are incubated and the results are counted up - one colony grows out from each bacterium, so it gives you a vague idea of what's going on. There's almost always bacteria; the engineers allow a "bacteria film" of non pathogenic bacteria to grow inside pipes, as this stops bad bacteria getting a foothold so easily. Of course, some of these bacterias are "oppertunistic", so if the animals get stressed, an outbreak can occur.
What else...On Thursday, I helped take sperm samples from mice for freezing. Male mice have a
Oh, and the vials are called "Eppindorfs".
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