The three dogs – two Malinois and a Jagdterrier (or Hunting Terrier), were taken to the nearby Sonnehof veterinary clinic after eating the meat last Friday.
Despite intensive medical treatment, all three animals died on Saturday.
After the incident, the Sonnehof clinic posted a warning on Facebook including images of the injuries and the objects found in the animals' stomachs.
"I don't know how or why anyone could do something like this," distraught owner of Hidalgo, Dart and Franky told regional Bern television station Tele M1.
In a statement released on Tuesday, Bern cantonal police said they had on Monday found remains of pieces of meat containing poison and dangerous objects in the garden in Rohrbach.
Investigations are ongoing and they have called for witnesses to come forward.