Just as a wasp paralyzes but doesn't kill the insect that it lays an egg on so wolves, likewise, avoid killing their prey for as long as possible so the meat will stay fresh longer (not consciously, of course, but this is the highly successful survival strategy that has evolved). Wolves "kill by consumption". Animals can linger for days. The dogs seems to treat the deer as though it were just an object.
https://en.wikipedia.org/wiki/Cattle_mutilation
In FBI records from 1975,
mutilation of the genitals occurred in 74% of cases,
mutilation of the rectum in 48% of cases,
mutilation of the tongue in 33% of cases,
mutilation of the eyes in 14% of cases.
According to a later survey taken by the National Institute for Discovery Science (NIDS),
mutilation of the genitals occurred in 85% of cases,
mutilation of the rectum in 76% of cases,
mutilation of the eyes in 59% of cases,
mutilation of the tongue in 42% of cases
After coming under increasing public pressure, Federal authorities launched a comprehensive investigation of the mutilation phenomenon.
The investigation was dubbed "Operation Animal Mutilation" and was headed by FBI agent Kenneth Rommel
Rommel's final report was 297 pages long and cost approximately $45,000.
It concluded that mutilations were predominantly the result of natural predation.
In 1993, documented photographic evidence of a 1988 mutilation surfaced that involved a human being near Guarapiranga, Brazil. An autopsy report concluded the procedure occurred while the victim was still alive, and the associated pain resulted in cardiac arrest.
The Guarapiranga Human Mutilation Case in Brazil - The autopsy report
The Guarapiranga Human Mutilation Case in Brazil
http://graphics.latimes.com/media/to...1a.jpg