signage, pointing to the Chousingha (Tetracerus quadricornis)

From your review it sounds like the zoo no longer has some of the species on this sign like giraffes and hyenas?

A quick google search says that the only giraffe died in 2015: Delhi zoo’s only giraffe dies - Times of India

I would go right at this sign...

I actually missed that the giraffes were still signed, despite the obviousness of it on the very photo I posted! (They are pictured on the zoo map too). There is a cage for striped hyaenas - I didn't see any inhabitants so I can't say whether they were there or not.