The leopard was found in a chicken coop in Mannarkad around 2am on Sunday.
On May 18, Poonawalla allegedly killed her and then chopped her body into 35 pieces and threw her body parts across various places over a period of 18 days.
Accused Saju stands trial on three counts of murder. The victims were his wife and two minor children.
Nayana was found dead at the house at Althara on February 23, 2019. Much of the scientific evidence has been lost. The probe should be expanded to include Nayana's friends and circumstances.
District police chief says their suspicion matches the doctor's findings, chemical examination ordered.
Roopkumar Shah, who retired from service last month from Cooper Hospital, didn't present any proof to back his claims.
The body of Kuttappan (83) was kept in the mortuary of the Idukki Medical College overnight due to the dispute.
The victim, Sharon's friend Greeshma has reportedly confessed to poisoning him with the intention of murder.
It is understood that Ambika left a suicide note, in which she took the blame on herself.
KC Lithara had committed suicide in Patna on April 26.