Why did they give birth to spotted, blotched and Akudim animals?
Malbim: This was a miracle, so no matter what Lavan would say (is Yakov's wage), Yakov will receive some of them.
Ha'Emek Davar: It was primarily Hashgachah, but Yakov did some action, so it would be a hidden miracle. A small act below causes a great act above. This is a Siman l'Banim