Dec. 18 is the Feast of St. Modestos, who lived in the Third Century and is the patron of domestic animals. In California, parishioners of Prophet Elias
Greek Orthodox Church brought their critters to church for a special blessing.
From the article:
"Blessed are you, O Lord, who for the sake of comfort give us domestic animals as companions," (Rev. Dennis Vierling) said. "Let us bless the name of the Lord."
He also read a prayer that included a selection from the Book of Genesis.
"In the beginning God created the heavens and the earth. And God said: Let the waters bring forth swarms of living creatures and let birds fly above the earth across the firmament of the heavens," Vierling read. "So God created the great sea monsters and every living creature that moves, with which the waters swarm, according to their kinds, and every winged bird according to its kind. And God saw that it was good."
(Some more information here