Brenda Coggin of Coggin Creek Stables said the air conditioner was emitting a mist and a chemical odor when she found the Australian shepherds dead on July 5. The dogs had bled through their noses.
Coggin did not immediately report the deaths and instead buried the dogs.
The Massachusetts Society for the Prevention of Cruelty to Animals and city Animal Control Officer Kenneth Frazer are investigating.
Frazer tells The Westfield News the air conditioner had been ruled out as a source of toxins.
Heat is a possible cause but an MSPCA spokesman says bleeding from the nose is not a symptom usually found when dogs overheat.
Information from: The Westfield (Mass.) News, http://thewestfieldnews.com
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