Darren O'Dea is suspended for Saturday's match after his red card at Aberdeen last week, which leaves 18-year-old Josh Thompson and 19-year-old Thomas Rogne as the only natural centre-backs.
Right-back Andreas Hinkel is back in contention after recovering from a thigh injury but Mowbray is contemplating the use of another full-back to add more experience to his back line.
While Loovens and Hooiveld could miss the Old Firm derby at Ibrox the following week, Mowbray is focused only on the visit of the Tannadice side as the Parkhead men try to claw back the 10-point gap Rangers enjoy over them at the top of the table.
"I don't think the injury situation is improving too much," the Celtic boss said.
"Andreas Hinkel trained today but Shaun Maloney is not expected back for a week or two.
"Darren O'Dea is suspended, Loovens isn't going to be ready, neither is Hooiveld.
"It is probably too strong to say Hooiveld has had a setback but he is not ready yet.
"It might not be (Thompson and Rogne in central defence).
"It might not be a centre-half.
"I might play Mark Wilson there, I might play Lee Naylor there, we will wait and see.
"You can play full-backs at centre-half no problem, it's been done many times, as long as they have a defensive mind and understand the danger.
"It's not ideal when your three experienced centre-halves are not available but we will have some options.
"You get concentration issues among young players.
"The ability to concentrate comes through age and understanding.
"I played the best football of my career after my 30th birthday, I knew the demands, where to stand and where to run.
"Sometimes young players minds are running 100 miles per hour for the whole 90 minutes and sometimes a little bit of composure and calm helps the team.
"Every team has injuries or suspensions throughout the season, that's why you carry a squad and that's why you have utility players, players who can play in three or four positions."
While Celtic's current defensive worries may lead some to ask why Mowbray allowed Gary Caldwell to join Wigan and Stephen McManus to go on loan to Middlesbrough in the January transfer window, the Hoops boss is comfortable with the changes he has made to his squad.
And in a week where he was given public backing by chairman John Reid and chief executive Peter Lawwell, Mowbray also called on the Celtic supporters to look to the long term.
Pointing back to his time as a player at Celtic in the 1990s when the then financially-stricken club was rescued by Scottish-born Canadian businessman Fergus McCann, who oversaw the extensive redevelopment of Celtic Park, Mowbray said: "When everybody is fit we will have five centre-halves, three experienced ones and two young ones.
"At this moment the three experienced defenders are all out.
"You can say we might not be as strong as at the beginning of the season but we could be sitting here with Loovens, McManus and Caldwell all injured.
"It's part and parcel of football."
He added: "I speak to my board every week and to me it comes down to intelligence.
"They understand the process of change we are going through and they are fully supportive of what we are trying to do.
"Nobody likes change but change needed to happen.
"I wouldn't want to get into any arguments with our supporters.
"They are right to want and expect the team to win and yet we are going through change.
"When I arrived as a player the club was going through change and sometimes change is for the better.
"Fergus McCann arrived and could you argue that the five-year plan benefited the club in the long run?
"It probably did. He built the stadium and gave the fans ownership of the club.
"I understand that it is difficult for people to see the long-term, they react in black and white, like a lot of journalists react in black and white, they think the result today is the only result that matters.
"My job and responsibility is to look beyond that."