It was responding to a release posted last week on the AQHA website in which the Animal Welfare Council said the predictions of experts had been borne out over the closure of the last remaining horse slaughter plants in the United States in 2007.
"The refusal to address the excess breeding of horses over the years has caught up with slaughter proponents," alliance representatives John Holland and Vicki Tobin said in a statement.
"Once again, they find themselves scrambling to find scapegoats for a problem they created," the pair said. It said the AQHA had "promoted overbreeding for decades".
The release revives the myth of the "unintended consequences" by claiming experts warned of a negative impact on horse welfare if slaughter was ended.
"Not only has horse slaughter not ended, but in 2008 - the first full year after the US plants closed - the 'unintended consequences' resulted in the second highest slaughter count since 1995," they said.
Holland continued: "There is nothing stopping anyone from sending their horse to slaughter.
"Blaming the closure of the plants for excess horses from an organisation that alone brags of registering in excess of 135,000 foals every year, is hypocritical."
The alliance pointed to US Department of Agriculture figures showing the leading breed on the slaughter trucks are Quarter Horses.
The welfare council release questioned the lack of funding in the federal horse protection legislation being promoted by anti-slaughter groups.
"Not stated is why the government should be responsible for privately owned horses or a breeder's choice to breed more than they can sell."
The alliance pointed to tighter European Union regulations effective from July which will require records of drugs given to horses.
"American horses are not tracked or considered food animals by any US government agency and routinely receive medications that are banned by the EU. Equine welfare advocates have been warning of the drug issue for years."
The alliance took the view that the scale of abuse and neglect is largely determined by economic conditions, they said.
Holland and Tobin said "activists" continued to be blamed for the "unwanted" horses that organisations such as the AQHA were responsible for producing every year.
The Animal Welfare Council statement outlined its concerns over the elimination of horse slaughter facilities in the US.
"It is clear that there will always be unwanted horses due to the fact that some horses simply won't meet their owner's expectations or will become ill or infirm," it said.
"The horse industry has responded to the unwanted horse problem and is developing and implementing programmes to both reduce the number of unwanted horses.
"Experts agree that the passing of the pending legislation to ban the transport and commerce related to horse processing would exacerbate all of these issues."
It argued that the proposed legislation banning slaughter, and the exporting of horses for slaughter, "will do nothing but cause greater suffering for horses, their owners, and the horse industry in general".