Spiritually considered, this teaches the separation of GOD'S people from the carnal world. 2 Corinthians 6:17-18. The abomination of the Hebrews. See Exodus 8:26.
Genesis 46:31-34
31 And Joseph said unto his brethren, and unto his father's house, I will go up, and shew Pharaoh, and say unto him, My brethren, and my father's house, which were in the land of Canaan, are come unto me;
32 And the men are shepherds, for their trade hath been to feed cattle; and they have brought their flocks, and their herds, and all that they have.
33 And it shall come to pass, when Pharaoh shall call you, and shall say, What is your occupation?
34 That ye shall say, Thy servants' trade hath been about cattle from our youth even until now, both we, and also our fathers: that ye may dwell in the land of Goshen; for every shepherd is an abomination unto the Egyptians.