Without vultures, animals that eat carrion as a part of their diet (called facultative scavengers, as opposed to vultures, which eat only carrion) proliferate to take advantage of the available nutrients in a dead carcass.
Garbage, compost, carrion and other organic material can host many toxins that lead to various symptoms in dogs who ingest it; this so called «garbage toxicity» may cause tremors and seizures and is often easily resolved when treated early.