A woman has been jailed for 26 weeks for keeping rescued horses in stables that were "more akin to a death camp".
Annette Nally, 50, was found guilty of causing unnecessary suffering and failing in her duty of care.
Inspectors found one dead horse and 12 emaciated animals at a stables in Stoke Prior, Worcestershire.
Nally was known for taking in rescue horses but breached the trust of those placing them in her care, a judge at Kidderminster Magistrates' Court said.
The inspectors had visited her stables in July last year. Two of the emaciated horses were later put down.
Warning: This story contains distressing images
The RSPCA later visited two other sites in Nally's control in Lapworth, Warwickshire, and Old Green Lane, Solihull. Seven more horses were found there in a poor condition.
It told sentencing Judge Ian Strongman that Nally, of Pryor Road in Oldbury, had worked with charities and organisations to provide homes for neglected and retired thoroughbreds.
The judge told Nally: "What you provided in the weeks prior to the intervention of the RSPCA was something more akin to a death camp.
"The number of horses affected and the desperate state in which they were found must make this one of the most serious cases of its type."
Carolle Lee-Jones, of High Horse Rescue, was at the stables when the horses were first found.
"I do rescue work and I have never seen such a horrific sight," she said.
"The judge gave the maximum sentence possible which we're grateful for."
As well as being jailed, Nally was banned from keeping animals for life.
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