Naples is spending money to boost the dwindling numbers of its distinctive mastiff, a massive guard dog said to date back to Roman times.

The southern Italian city has spent some 600,000 euros over the last two years to fund kennels and a new breeding programme for the Neapolitan mastiff ('mastino Napolitano'), the local media reported Friday.

The mastiff was once one of Italy's most popular guard dogs but has been tainted by association with a recent spate of dog attacks.

It has also become a status pet of mafiosi.

The dog is said to have been trained by the Romans to run under enemy horses and disembowel them with spiked collars.

A Neapolitan mastiff featured in the 2007 film American Gangster.

Similar but smaller dogs had a prominent role in the epic opening battle scene of Gladiator (2000).