Injuries to Andrea Barzagli and Giorgio Chiellini mean that Ventura will be without two thirds of the so-called BBC defence for Saturday's World Cup qualifier in Liechtenstein and the following Tuesday's friendly against Germany.
With midfielder Claudio Marchisio also missing, Ventura said it was the perfect time to experiment with youngsters.
His 29-man squad for the two games includes six uncapped players, 17 who are aged 25 or under and there are only 12 survivors from Euro 2016.
"It appears that fate, through the many injuries, wants us to speed up the process of changing the generation," Ventura told reporters on Monday.
"It's a very important moment in terms of unearthing new talent and I would be short-sighted and not very intelligent if I were to not take advantage of it. We are starting a new journey, taking note of what is on offer at this time."
Ventura appeared to take a dig at Conte, who led Italy to the Euro 2016 quarter-finals and was widely praised for galvanising a team that few Italians had much faith in.
"The last European championship has left us with the oldest squad in the 150 years," said Ventura, who had previously praised Conte and said his team merely needed fine-tuning.
Italy's 23-man squad in France had an average age of around 28 and a half, which is not exceptionally high for an international tournament.
Ventura's squad included surprise choices included off-form forwards Manolo Gabbiadini and Simone Zaza while Mario Balotelli was overlooked despite his revival with French side Nice.
"These players are not enjoying their best moments, but as they are assets of the national team, we need to help revive them and get them back to being the players they were," Ventura said.
On Balotelli, he said that "we can't think that a person's history has changed in two months".
Ventura, 68, has never won a major title in his career although he has a good reputation for nurturing young talent.
Italy are second in European World Cup qualifying Group G with seven points from three games, behind Spain on goal difference.
Their match with Germany will be a repeat of the Euro 2016 quarter-final which the Germans won on penalties after a 1-1 draw.
(Writing by Brian Homewood in Berne, editing by Ed Osmond)
