Lab Notes

✶ April 10, 2026 ✶

I pick up after my dogs often enough... let's test it!

New Barkings: The Witch and Dog Droppings

I figure with the amount of times dog owners clean up their dog's feces throughout their life, I bet very few of them wonder 'what's in this stuff?'. So today, we're going to look at just that! Yes, it's a bit on the gross side for those that have less than iron-clad stomaches. For the rest of us, buckle up!

Experiments: Swift 380T Microscope @ 400x & 1000x magnification

Organism	Observations	Photos
Canine Feces Micrococcus luteus	Straight up. This was hard. Simply put, as one could imagine, sampling a direct dap of pure feces gives a plethora of different types of bacteria. So much that it was hard to see what it was I was looking at. I had put some of this sample on a nutrient-rich agar and incubated it for 3 days at 32°C, this is one of the images you can see here. It came back quite the golden-yellow, with there being about 50 colonies that could be counted, and a mass of colonies that I couldn't in good faith give an estimate for. Each colony was round and roughly the same size of 1mm (I need a µmm measuring device). The morphology seen under the microscope was that of highly motile and non-motile combinations of diplobacillis and tetrad cocci bacteria. And the Gram stain indicates a mix of both positive and negative. However, seeing as the majority of the bacteria seen was Gram-positive tetrad-arranging coccus, on top of the coloring and macrophorology of the agar colonies, I went with Micrococcus luteus. This makes the most amount of sense if this is, indeed, the biggest bacterial player we're dealing with. It's generally considered harmless to humans, is non-pathogenic, is a commensal organism, and rarely becomes an oppotunistic pathogen. This makes sense because humans would have become sick A LOT more often seeing as how often we handle dog feces (some on a daily basis, and some never in their lives).

Organism

Observations

Photos

Canine Feces

Micrococcus luteus

Straight up. This was hard. Simply put, as one could imagine, sampling a direct dap of pure feces gives a plethora of different types of bacteria. So much that it was hard to see what it was I was looking at.

I had put some of this sample on a nutrient-rich agar and incubated it for 3 days at 32°C, this is one of the images you can see here. It came back quite the golden-yellow, with there being about 50 colonies that could be counted, and a mass of colonies that I couldn't in good faith give an estimate for. Each colony was round and roughly the same size of 1mm (I need a µmm measuring device).

The morphology seen under the microscope was that of highly motile and non-motile combinations of diplobacillis and tetrad cocci bacteria. And the Gram stain indicates a mix of both positive and negative. However, seeing as the majority of the bacteria seen was Gram-positive tetrad-arranging coccus, on top of the coloring and macrophorology of the agar colonies, I went with Micrococcus luteus.

This makes the most amount of sense if this is, indeed, the biggest bacterial player we're dealing with. It's generally considered harmless to humans, is non-pathogenic, is a commensal organism, and rarely becomes an oppotunistic pathogen. This makes sense because humans would have become sick A LOT more often seeing as how often we handle dog feces (some on a daily basis, and some never in their lives).

Location of sample

Dog - Not sure which one gave us the sample.

Dog-given consent by both Daphne and Velma. May or may not had been bribed with cheese.