The poem has a literal level and a figurative level. Why has the poet chosen 'tigers' and 'sheep' to convey his message?

Though literally the poem talks of a short story in which a shepherd made a concord with a king of tigers to maintain peace among the two communities. However, if one tries to gauge, there is more to it than just a jungle story. It speaks of the distinction between the proprietor and the proletariat. It is about the class struggle and the oppressor and the oppressed. The shepherd is the politician, the ruler, as depicted in the poem, and other sheep are subjects. The sheepdog, is the warrior, the army, to protect sheep. However, shepherd wants to maintain his sovereignty, so sacrifices a few sheep to maintain a cordial relation with the tigers and goes on signing the pact. It is depicted how the rulers sacrifice their people to maintain their regime.