The event will be attended by about 28,000 dogs
The Crufts dog show has begun in Birmingham, after losing a major sponsor and BBC television coverage.
The RSPCA and sponsor Pedigree have pulled out of partnerships with Crufts, following claims about dog-breeding malpractice in a BBC documentary.
However the Kennel Club, which runs Crufts, said it expected visitor numbers at Birmingham's NEC would match last year's record crowd of 160,000.
The event is being broadcast live on the internet for the first time.
In December the BBC said it had suspended coverage in 2009 pending further investigations into the health and well being of pedigree dogs in the UK.
It said the decision followed the Pedigree Dogs Exposed programme on BBC One in August 2008, which "identified serious issues affecting the health and welfare of some pedigree dogs".
The BBC said in December it was not able to reach agreement about how to handle televising "the so called 'at-risk' breeds of pedigree dog".
But it added it recognised the Kennel Club was taking "significant steps" to address these problems by introducing changes to the breed standards and it remained keen to continue discussions with the club.
The four-day event will be attended by about 28,000 dogs, the third highest figure since the show was founded in 1891.
Kennel Club spokeswoman Caroline Kisko said: "[We] are pleased to go online... because, although the show will no longer be on the BBC, we know that it is the world's best platform to bring together those organisations and individuals who care about dogs.
"We have the continued support of many high-profile veterinary organisations and dog welfare charities.[We] want to ensure that we continue to engage the support of those dog lovers who are unable to get to the show."