Ballymena hooker, John Andrew, makes his first start in the tournament with Donnan named in the second-row and Joyce selected in the back-row.
With Stuart Olding called to provincial duty, Rory Scholes is the only Ulster representative in the back-line and starts on the left wing.
Speaking ahead of the game, Ruddock said “Despite the fact that we are missing a few front liners due to injury and unavailability we have still been able to select a strong side.
“We are looking forward to a very physical encounter against the Italian side.
“We are obviously looking to build on our win from last week to take us through into the IRB Junior World Championship.
“We have added some new combinations to the bench as we look towards the summer.”
Ireland Under-20 Team v Italy (Stadio dei Marsi - Friday, 15th March 2013, kick-off 7.00pm local time /6.00pm GMT)
15 - Darragh Leader (Galwegians/Connacht)
14 - Darren Sweetnam (UCC/Munster)
13 - Tom Daly (Lansdowne/Leinster)
12 - Rory Scannell (Dolphin/Munster)
11 - Rory Scholes (Belfast Harlequins/Ulster)
10 - Steve Crosbie (Old Belvedere/Leinster)
9 - Luke McGrath (UCD/Leinster)
1 - Peter Dooley (Lansdowne/Leinster)
2 - John Andrew (Ballymena/Ulster)
3 - Ryan Furniss (Worcester/Exile)
4 - Sean McCarthy (Shannon/Munster)
5 - John Donnan (Ballynahinch/Ulster)
6 - Conor Joyce (Malone/Ulster)
7 - Josh Van Der Flier (UCD/Leinster)
8 - Ryan Murphy (Dolphin/Munster)
Replacements:
16 - Bryan Byrne (UCD/ Leinster)
17 - Adam Boland (Lansdowne/Leinster)
18 - Brian Scott (UCC/Munster)?
19 - Jerry Sexton (St. Mary’s/ Leinster)
20 - Peadar Timmins (UCD/Leinster)
21 - David Shanahan (Clontarf/Leinster)
22 - Eogháin Quinn (Lansdowne/ Leinster)
23 - David Panther (Corinthians/Connacht)
Ireland Under-20 RBS 6 Nations Fixtures and results 2013 (All Kick-off Times GMT):
Fri 1st Feb 19:10 Wales U20 v Ireland U20 17-15
Fri 8th Feb 19:35 Ireland U20 v England U20 16-15
Fri 22nd Feb 19:30 Scotland U20 v Ireland U20 Netherdale 21-20
Fri 8th Mar 19:45 Ireland U20 v France U20 Dubarry Park 22-5
Fri 15th Mar 19:00 Italy U20 v Ireland U20 Stadio del Marsi