Leading Edge 2021 Issue 2

6 LEADING EDGE - 2021-2 Bristol Zoo Gardens is a conservation and education charity founded by Henry Riley, a local physician and is the fifth oldest zoo in the world. It first opened its doors on 11th July 1836 and has since helped to save 175 species from extinction through breeding programmes and has established over 30 field conservation and research projects globally. Charlotte Day, one of the resident vets at the zoo tells us about a recent study they conducted with Jock, their 32 stone male silverback gorilla. “Jock has had symptoms of gastrointestinal disease for quite a while with vague symptoms such as losing weight, being lethargic and having intermittent diarrhoea. We have tested him for various parasites but haven’t been able to get to the bottom of what is causing his symptoms and so we wanted a noninvasive way of finding out if he possibly had an inflammatory bowel disease (IBD). The problem with gorillas is that to do any investigations we need to give them a general anaesthetic. As you can imagine they wouldn’t co-operate with procedures such as an endoscopy. General anaesthetic presents considerable risk and is a major procedure. Jock also isn’t a young gorilla and has other underlying medical issues, so we really don’t want to anaesthetise him unless it is absolutely necessary. Calprotectin? I was aware that calprotectin testing is used in humans to assess for IBD but didn’t really have any data about its use for assessment in veterinary practice. Researching online I came across the BÜHLMANN Quantum Blue® faecal calprotectin test. This seemed ideal for our purposes because a lot of laboratories won’t take faecal samples from non-human primates due to the risk of zoonotic infection. Being able to perform the assay ourselves looked like the perfect solution and it seemed relatively straight forward. Because we didn’t really have any data on faecal calprotectin in gorillas we decided to test all of them and compare the results to Jock to see if there was a difference in their faecal calprotectin concentrations. Obtaining faecal samples from gorillas Normally, if we want to test a faecal sample from an animal then the vets will put a request in to the keepers to organise this. However, most of the animals are housed in groups, so identifying who has produced a specific sample is not always easy. The keepers can’t go in whilst the gorillas are in the enclosure; they need to wait until the gorillas are moved into a separate section and then they can go and collect the samples. Fortunately, the gorillas have all been trained to go into individual pens for eating so that they can have tailored diets. So, we can easily feed them edible food dyes to identifying which faeces belong to which gorilla. However, on consultation with Alpha Laboratories it was realised that this was not a good approach because the assay relies on the development of a coloured line in the lateral flow cassette and the dye might influence the result. For this reason we also excluded beetroot from the gorillas’ diet whilst we were doing the testing, just in case. Investigating Gastrointestinal Disease in Gorillas by Charlotte Day, Veterinary Resident, Bristol Zoo Gardens Jock, the silverback gorilla, and his fibrous diet.