Handling cow manure in school science laboratories: Can cow manure be used for practical activities in school science laboratories? Are there any regulations regarding handling cow manure?

Handling cow manure in school science laboratories: Can cow manure be used for practical activities in school science laboratories? Are there any regulations regarding handling cow manure?
Laboratory signage for microbiology: Is it mandatory for school science laboratories to have a biological hazard sign on laboratory doors and equipment such as incubators and fridges where microorg