Lulu, the cute little antelope taken as a pet by the Baroness, is pretty much directly a symbol for the Baroness herself. She is described as "the pride of the house" (1.4.24) but also as having the "so-called devil in her" (1.4.23). She's everybody's favorite, but also rules by fear.
We can't help but think of the Baroness, a lone woman ruling the roost. Baroness Blixen does insane-o things: like, for example, she forces her servants to go out and find a baby antelope she saw earlier that day. If they can't deliver, she promises to fire them all. Whoa, there, Baroness. Slow down, diva. You're sounding like you're on The Real Housewives of British East Africa.
What's especially telling about Lulu is that she's half domesticated, half wild. And the Baroness is a noblewoman with lots of social responsibilities, but one who likes to get away from it all and run around in the wilderness of Africa. The Baroness starts to think of herself as becoming less Danish and more a part of Africa, and in the Baroness' mind (which is a product of a pretty racist time), Denmark is civilization and Africa is the untamed wild.
We also can't ignore the fact that Lulu is a girl. Just like the Baroness, who seems to run the farm with the help of men (but definitely as their boss) Lulu brings all her daughters around close to the house. As the Baroness puts it, "It seemed that we had to do with a forest matriarchy" (1.4.48). Girl-power is an underlying theme throughout the memoir, and Lulu is the perfect embodiment of it.
And don't forget that Lulu, like Blixen, has a great love affair. Lulu leaves the house one day and Blixen is scared that she's deader than a doornail, but nope—Lulu is just shacking up with a handsome buck she meets one day. We have to wonder if that's what people in Denmark think of Blixen: "Blixen? Is she dead? No, she's just having a love affair with a handsome pilot named Denys? Oh, phew."