18 March 2010

Streaking...More Than Just a Dare.

I've had some people recently ask me why I've given up on meat and animal products. Besides my absolute love of anything animal and not wanting to contribute to their unnecessary and cruel slaughter, try having a veterinarian - a farm animal vet (cows, sheep, pigs, goats) - as a microbiology instructor and see if you want to put animal flesh in your mouth ever again. Man, she can tell some stories of the nasty that lives in those things.
 
She's also good at telling you about the nasty you can get from those animals - no matter how clean or well cooked you think your food is. I could go on (mmmm...prions. Tiny bits of loose proteins that can cause neurological damage - think BSE (Mad Cow) and CWD (chronic wasting disease) found in deer (take that, hunters) - and the vaccine has only been tested in mice. According to the CDC, the occurrence of bovine spongiform encephalopathy (BSE) and its transmission to humans indicate that animal prion diseases can pose a significant public health risk. Recent reports of secondary person-to-person spread further illustrate the potential public health impacts of BSE. I think I'll take my chances on carrots.) but I'll move onto something even more disturbing.

 

And kinda fun. We got to play with toxic substances last night.

 
Classmate: "So, is that the culture taken from that dog's ear from last time?" (See? Vet as an instructor. She brings all sorts of fun stuff in.)
 
The culture from the dog really, really stunk. Bad. It was not a pleasant experience.
 
Dr. Moore: "No, It's just some E.coli."
 
Oh. Just E.coli. Well then. That's good.
 
Anyone need a good excuse for missing work the next couple days?
 
And that is how we began our microbiology lab last night.
 
We were doing streak plates, where you take an inoculating loop, dip it in the culture (in this case, a scary-looking vial of E.coli), then streak the loop over 1/4 of your petri dish of agar in order to grow colonies.
 
Here's Mary demonstrating step #1:
 
 
Then you sterilize the loop, bring it to the first 1/4, turn the dish 90 degrees and streak the loop from section 1 to section 2.
 
Here's me demonstrating step #2
 
 
1/2 of your dish is now covered. Repeat until the whole dish is streaked, with the goal of getting fewer and fewer organisms per streak in order to break out the colonies.
 
Here is Jennifer completing step #3, and Mary did the final quadrant.  
 
 
And I just had to get a picture of myself holding the E.coli vial just to freak out my family.
 
 
I really need a vacation.
 
 
Disclaimer: This was for picture purposes only. I would not be that mentally incapacitated to actually think of licking the vial.
 
There's a picture of the four quadrant technique here, and really pretty pictures of all sorts of different streaked plates here.
 
And this is how we study bacteria and diseases.
 
If you think this is boring, well, deal with it. I think it's fascinating, so therefore you'll have to suffer through some science-y posts the day after my class.

1 comment:

Mel C said...

After this post (and throwing up a little in my mouth)... I might becoming a vegetarian!