Lovely shot. This looks like a zoo that could do with someone kind to give them time and money; they have some wonderful animals but a lot of the housing looks AWFUL
The colours of the marsh deer are also very similar to those of the maned wolf ! I am not really sure what the husbandry problem of the marsh deer is. At least Berlin Zoo kept them alive for many years, even though breeding was apparently poor. Also it seems that there was never much interest by zoos to keep this species, even though they are so beautiful. Santa Cruz had a nice group when I was there, but sometimes being located within the natural distribution area is already a big part of the key to success. I don't think they will be in any zoo outside of South America in the foreseeable future.
@Saro yes I agree and would add the pampas / pantanal cat too which has a strikingly similar colouration to both the deer and the "wolf".
I think that it could be down to a phenomenon known as "countershading" / "Thayer's law" but as far as I know there has never been any research done to prove this.