It is a second spell with Boro for the 20-year-old striker.BCFC
It is a second spell with Boro for the 20-year-old striker who spent the second half of the 2015/16 campaign at the Warwickshire club.
The forward has been in decent goalscoring form for Blues Under-23s this season, finding the back of the net six times in his 14 appearances.
McFarlane, who penned a fresh one-year professional deal with Blues earlier this year, joins a struggling Nuneaton side that are currently 20th in their division with 17 points from their 19 games.
They have not won in their last five league games.
Boro have a break from league in action this weekend as they welcome North Ferriby United to the LDJ Solicitors Stadium on Saturday in the FA Trophy.
The loan will run until 2 January, 2008, and McFarlane will be elgible to play in the Trophy.
McFarlane is the third Blues youngster to be given the opportunity to go out and play First Team football this week, after Olly Mulders and Matthew Timms joined fellow Northern Premier League outfit Mickleover Sports on Thursday.