The BBC breached its own guidelines on accuracy after it re-edited a controversial programme that had already been criticised by watchdog Ofcom.
The BBC Trust's editorial standards committee (ESC) investigated after complaints about Pedigree Dogs Exposed.
The programme, which examined how inbreeding could affect the health of dogs including Rhodesian ridgebacks, had been the subject of an Ofcom ruling in 2009 that it was unfair in some aspects of its treatment of the Kennel Club which organises the Crufts dog show.
It was subsequently re-edited in preparation for broadcast abroad.
But the Rhodesian Ridgeback Club of Great Britain (RRCGB) and a representative of the South African International Breed Foundation complained the BBC had failed to correct errors in the process.
The original Ofcom ruling stated it was inaccurate to describe the breed's ridge as "a deformity" and as a "mild form of spina bifida".
The RRCGB said the re-edited programme still linked the issue of "spina bifida" and "deformity" and made it appear the club was culling puppies.
The committee found that "whilst the script had improved it was still imprecise".
Its report, published today, states: "The committee agreed that it would have been accurate to describe dermoid sinus, the condition the dogs suffer from, as being "similar to a mild form of spina bifida" but that it was imprecise to suggest that dermoid sinus was "a mild form of spina bifida"."
It added that given the Ofcom ruling "it was incumbent upon the BBC to strive to achieve clarity and precision in the script at this point" and found there "had been a breach of the guideline on accuracy".The committee also found the programme makers had continued to include a quote from RSPCA chief vet Mark Evans describing the ridge as a "deformity" despite it having been deemed by Ofcom as unfair.
It ruled programme makers should have offered the RRCGB a right of reply to the allegation and the failure to do so was "a breach of the guideline on fairness".
The original programme, screened on August 19 2008, led to the BBC, which had broadcast the Crufts dog show every year since 1966, suspending its coverage pending further investigation into the health and wellbeing of pedigree breeds in the UK.