* [[spoiler: The Tod's]] HeroicSacrifice.
* Snitter blaming himself for the death of his master.
* The entire [[TearJerker/WesternAnimation animated film]].
* The poor rat in the skinner box.
* Oh, boy, you like monkeys? Well, we get treated to seeing a very cute baby monkey steadily losing it's sanity inside an isolation chamber. As the dogs walk down a long corridor, they accidentally startle 3 monkeys, each in a restraint chair with invasive wires going into their skulls. Perceiving the dogs as dangerous predators, the monkeys shreik and struggle in vain to escape.