Debbie Bell was with her seven-year-old daughter Rosie when they found one of the family's horses disembowelled after having its stomach slashed in Eyam, Derbyshire, and another drugged and abused.
The surviving animal was moved closer to the Bell's home near Sheffield and has since suffered three other attacks, leaving it close to death once.
The horse twice had shapes slashed into its body, blood drawn from veins in its neck and was sexually abused.
Each attack is accompanied by gothic circles or pentangles made of stone.
They are a handful of a spate of incidents in Sheffield and Derbyshire dating back to last year which are linked by police with occult followers, sparking a three-day stake out operation two weekends ago.
Mrs Bell said: "My daughter was devastated when she saw what happened, the horse that died was going to be hers one day.
"She had trouble sleeping for a week afterwards and keeps thinking the attackers are going to come back.
"It's almost as if we are being watched. One attack happened when I went to the shop for half an hour.
"They always go to such an effort not to leave any footprints or evidence that the police can go on, and every time they leave shapes in the field.
"Once all the grass in a field was flattened by symbols. It's spooky."
Police are still investigating the attacks and are anxious for anyone with information about the culprits to contact them.
There has never been an arrest made in connection with such an attack in this country, police say.
Anyone with information should contact police on 0114 220 2020.