“Go back to Pharaoh,” the LORD commanded Moses. “Tell him, ‘This is what the LORD , the God of the Hebrews, says: Let my people go, so they can worship me.
If you continue to hold them and refuse to let them go,
the hand of the LORD will strike all your livestock—your horses, donkeys, camels, cattle, sheep, and goats—with a deadly plague.
But the LORD will again make a distinction between the livestock of the Israelites and that of the Egyptians. Not a single one of Israel’s animals will die!
The LORD has already set the time for the plague to begin. He has declared that he will strike the land tomorrow.’”
And the LORD did just as he had said. The next morning all the livestock of the Egyptians died, but the Israelites didn’t lose a single animal.
Pharaoh sent his officials to investigate, and they discovered that the Israelites had not lost a single animal! But even so, Pharaoh’s heart remained stubborn, and he still refused to let the people go.
References for Exodus 9:7