Boothroyd moved for the teenage centre-half following injuries to Pat Baldwin, Paul Reid and Lee Beevers.
Batth has put pen to paper on an initial one-month deal and should be in contention for Saturday's visit of Hartlepool along with fellow loan signing Kayode Odejayi.
Meanwhile, the U's have been boosted by the news that Ashley Vincent's ankle injury is not as serious as first feared.
The winger was stretchered off after scoring against Swindon last weekend, but an X-ray has confirmed he did not break any bones.
"It will be touch and go for Saturday, but on a positive note it is always pleasing when injuries aren't as serious as first thought," said physio Tony Flynn.