Greetings dear @lemouth, the urea that you mention in the article is used as an alternative to supplement the nitrogen deficiency that may exist in pastures, to supply it, it can be applied on forage mixed with molasses.
Its use is delicate, not all producers use it and whoever does it must establish some criteria such as those mentioned in the article to avoid poisoning in the animal.
So long, have a great week.
Thanks for all these clarifications!
Cheers!