exodus 9:3 Behold, the hand of the LORD is upon thy cattle which is in the field, upon the horses, upon the asses, upon the camels, upon the oxen, and upon the sheep: there shall be a very grievous murrain. - Free Bible Online

      3-5. Behold, the hand of the Lord is upon thy cattle--A fifth application was made to Pharaoh in behalf of the Israelites by Moses, who was instructed to tell him that, if he persisted in opposing their departure, a pestilence would be sent among all the flocks and herds of the Egyptians, while those of the Israelites would be spared. As he showed no intention of keeping his promise, he was still a mark for the arrows of the Almighty's quiver, and the threatened plague of which he was forewarned was executed. But it is observable that in this instance it was not inflicted through the instrumentality or waving of Aaron's rod, but directly by the hand of the Lord, and the fixing of the precise time tended still further to determine the true character of the calamity (Jer 12:4).

JFB.