Along with eggs, I've used previously unopened sour cream WAY (, way) past the date and do the same as you once it's opened. Between the pasteurization of the original milk and then innoculation with good microbes, the lower moisture content and the acidity, it's not a very hospitable environment for pathogens.
Cauterization definition, to burn with a hot iron, electric current, fire, or a caustic, especially for curative purposes; treat with a cautery. See more. Dictionary.com
Neutering is the surgical procedure that renders a male or female cat or dog unable to reproduce. In males, the surgery (called castration) entails removal of the testicles, leaving an empty scrotal sac that soon shrinks. The testicles produce sperm and are the primary production site of the hormone testosterone.