RSPCA should be stripped of its power to prosecute animal welfare cases, a Commons select committee has been told.
The Environment, Food and Rural Affairs Committee said there was a "conflict of interest" in the charity's role of bringing private prosecutions as well as fundraising and campaigning.
They called on ministers to change the law so the RSPCA could continue their welfare work, but hand over criminal charges to the Crown Prosecution Service.
The charity defended their work, and said the recommendations of the "small group of MPs" did not reflect the opinion of Government or animal welfare groups.
Committee chair Neil Parish said: "The RSPCA does important working investigating animal welfare cases. And I would like to see its dedicated and professional staff continue that vital work.
"The committee is not convinced, however, that the RSPCA is in a better position than the Crown Prosecution Service when it comes to prosecuting animal welfare cases.
"It should step back from making prosecutions itself, continuing instead to work closely with the police and prosecution service to protect the welfare of animals."
The RSPCA infamously prosecuted the Heythrop - former prime minister David Cameron's local hunt - but only after vast sums were spent.
However they also attracted negative publicity for its failed prosecution of a family for alleged cruelty to its cat.
RSPCA chief executive Jeremy Cooper said: "Our research shows that 89% of the general public back our prosecutions work and they will be confused why a small number of MPs would suggest stopping the RSPCA carrying out a role which we are very good at and which is paid for by public donations rather than out of taxes."
The president of the British Veterinary Association, Gudrun Ravetz, said the RSPCA move was a "disappointing distraction" from the report's other recommendations.
The committee recommended the maximum penalty for cruelty should be increased to five years, and called for a ban on third-party sale of dogs - so they can only be purchased from licensed, regulated breeders or approved rehoming organisations.