I read from dog-ear to dog in the manger.

Please check out "Dog Eat Dog" by "Weird Al" Yankovic.

https://www.youtube.com/watch?v=TuSlrEoPWoQ

The history of why soldiers might be called "dogface".

https://en.wikipedia.org/wiki/Dogface_(military)

Dogfish are often found hunting in dog-like packs.

https://en.wikipedia.org/wiki/Squalidae

Do you want more info and examples of doggerel poetry? You're in luck!

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