"The rats here are particulary repulsive, they are so fat-the kind we all call corpse-rats"

Robert Graves wrote in Goodbye to All That:

Rats came up from the canal, fed on the plentiful corpses, and multiplied exceedingly. While I stayed here with the Welch, a new officer joined the company and, in token of welcome, was given a dug-out containing a spring-bed. When he turned in that night he heard a scuffling, shone his torch on the bed, and found two rats on his blanket tussling for the possession of a severed hand.