Sell eggs at the Merchant
The official description confirms that chickens lay eggs and that carried eggs can be sold to the Merchant.
Observed egg examples
One screenshot-backed run showed a 2.8 kg Cheese Egg and a 22 kg Zombie Egg. The report describes payouts as weight-sensitive, so these are examples—not fixed values for every egg.
Do not budget from one haul
The same report observed heavier mixed batches around $40K–$69K, but composition and weights vary. Record your own sale before treating that range as repeatable.