The description of Jesus as a shepherd is metaphorical. It has nothing to do with literal sheep. Although, literal shepherds guarded the flock and raised them to maturity, they harvested both wool and meat from them.

Jesus being referred to as a shepherd was intended as a metaphorical description of the care and devotion Jesus has for his human flock, the believers of the church.

This particular descriptive was used because, during the time Jesus lived, the occupation of shepherd was a common, and well respected one. The comparison between the caretaking aspects of the roles of Jesus to humanity, and a shepherd to his flock was intended to illustrate a relationship, not proscribe a meal choice.