Animal rescuers have described conditions at Dublin's Smithfield market as "mayhem".
The monthly fair, which is a hit with both locals and tourists alike, was described as "anarchy" by DSPCA officials.
The DSPCA reported two particularly shocking cases of abuse that took place last weekend and resulted in a six-week -old colt being placed in intensive care.
Orla Aungier, of the DSPCA, said they are often shocked by the treatment animals receive at the hands of some of the carers at the market.
"The Smithfield market has been an ongoing issue with us for many years," she said.
"On Sunday, we found a six-week-old colt which had been beaten severely. We also seized three puppies, all of whom were six weeks old and being sold for €10.
"The pups are in the care of the Dublin SPCA and will be fostered until old enough to be vaccinated and re-homed."
The colt, meanwhile, needed an emergency horse box to transfer it to Rathfarnham.
"It was attended to by our veterinary surgeon and transported to the Dublin SPCA shelter in Rathfarnham where it is receiving intensive care," Ms Aungier said. The SPCA inspectors are also afraid of attacks.
"Our staff have to wear stab- proof vests as there have been many incidences where they have been attacked or have had missiles thrown at them," Ms Aungier said.
"It was anarchy really, there was fighting and several other incidents involving crowbars and even one young man was spotted carrying a sword."
A Garda spokesperson confirmed that a minor incident was reported at Smithfield market on Sunday, however no arrests were made.
Gardai are also aware of the incident concerning the young horse and two puppies.