Q: Did the Apostles and the early church pay tithe, practice it and preach it as Christian duty in the early church?
A: There are several instances where the practice of tithing is mentioned in The Urantia Book. The most notable in regards to your question is the following one, which was a commentary following the narrative of a Sabbath breakfast that Jesus attended at the home of Nathaniel. This breakfast was also attended by a group of lawyers and Pharisees, who scolded Jesus for not washing his hands, as was the ceremonial practice of the Jews in those days. (You can read the whole story of that breakfast HERE)
At the end of the narrative, we read:
In another passage, Jesus says this:
166:1.7 There were just three things to which the Pharisees paid particular attention:
1. The practice of strict tithing.
2. Scrupulous observance of the laws of purification.
3. Avoidance of association with all non-Pharisees.
At this time Jesus sought to expose the spiritual barrenness of the first two practices...
This last passage seems to suggest that Jesus felt tithing was a worthwhile to do, "within reason, " but (in my opinion) mainly because it was a requirement of the Jewish religion. Jesus early learned to tithe—and you can read about that HERE. But as he matured, he witnessed the "spiritual barrenness" of the practice (as well as other Jewish practices), as he felt that it was disconnected from the "weightier matters" of faith and mercy..."
175:1.17 “Woe upon you, scribes and Pharisees and all other hypocrites who make sure that they tithe mint, anise, and cumin and at the same time disregard the weightier matters of the law — faith, mercy, and judgment! Within reason, the one you ought to have done but not to have left the other undone. You are truly blind guides and dumb teachers; you strain out the gnat and swallow the camel.
In light of these passages which make clear how Jesus felt about the practice of tithing, I would doubt that the practice was followed by the apostles, but I can't say for sure. Nowhere in The Urantia Book do we read about the apostles either preaching tithing, or practicing it.
I did find a website HERE that gives a Biblical history of tithing. It evidently was not brought into practice in the Christian church until around the year 600. And, tithes were given according to the early Bible recommendations—crops and livestock, etc...and not necessarily money.