SB 10.15.31
punar asadya samrabdha
upakrosta parak sthitah
caranav aparau rajan
balaya praksipad rusa
Translation:
Moving again toward Lord Balarama, O King, the furious ass situated himself with his back toward the Lord. Then, screaming in rage, the demon hurled his two hind legs at Him.
Purport:
The word upakrosta indicates an ass and also one who is crying out nearby. Thus it is indicated herein that the powerful Dhenuka made horrible, angry sounds.