Three peacocks and five peahens were found dead at a field at Tadvi Falia, 200 km from here, Alirajpur's Divisional Forest Officer (DFO) R S Sikarwar told PTI.
"The postmortem report revealed that the birds died after eating wheat seeds on which chemical fertilisers had been sprayed before sowing," he said.
The DFO said the peafowl must have overeaten the seeds sprinkled with chemicals.
"Not drinking water after the consumption of seeds must have made things worse and led to their death," he said.
According to the official, Alirajpur district is home to around 400 peafowl.