Date of publication: 2017-09-04 02:16
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The human Petri dish samples mostly have the same brown flat bacteria or white bacteria, unlike the very diverse dog samples. Most of these samples would range from having few to moderate bacteria levels. These are blood agar plates that allow both gram-negative and gram-positive bacteria to grow.
At once encyclopedic and intimate a tour de force.
Kirkus Reviews This might be the most important book about dogs written in a decade.
Patricia B. McConnell , author of The Other End of the Leash Kerasote has produced a masterpiece.
Elizabeth Marshall Thomas , author of The Hidden Life of Dogs
The gram stain of bacteria is a way to classify bacteria based their cell walls. To do the gram stain, you put a sample of the bacteria on a plate, stain it purple with a chemical, de-stain it with alcohol, and then stain it with a pink chemical. If the bacteria stain purple, they are gram-positive, which means that their cell walls absorbed the purple chemical. If the bacteria are pink, they are gram-negative, which means that their cell walls didn't take up the purple chemical but did take up the pink. Gram-positive cells are usually found in the mouth or on the skin, and gram-negative cells are usually found in the intestines.
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When Ted Kerasote was ready for a new dog after losing his beloved Merle who died too soon, as all our dogs do he knew that he would want to give his puppy Pukka the longest life possible. But how to do that? So much has changed in the way we feed, vaccinate, train, and live with our dogs from even a decade ago. Read more
I recorded the quantity of bacteria on each plate, and I tried to estimate how many different bacterial colonies were on each plate. (I had to estimate because it is nearly impossible to find the exact number.) When I got home, I averaged the data to better understand it. I first found the average quantity of dog and human total bacteria, gram-positive bacteria and gram-negative bacteria. To do this, I assigned a rating scale in which rare = 6, few = 7, moderate = 8, and many = 9. I averaged the results and recorded them in the data table.
I am so grateful to have been able to experience working in a university lab at the age of 68. I have learned so much working with the agar plates and bacteria. I will be perfectly happy if I don't win, because the experience was incredible and very educational, and I am so happy I get to share my discoveries with the world.
8. Variables, Controls and Sample Size: The only variable I was testing was the difference between species. The control was the human saliva. I had five human samples and seven dog samples because of the limited materials the lab offered me.