Surgery in captive wild animals kept in zoological collections

Thankfully, the vast majority of animals in well managed zoos, lead long healthy lives, with no need for surgery. Occasionally, however, one of these captive wildlife patients will need an operation.

Factors complicating Zoo Surgery
Zoo animals are usually uncooperative, some can be dangerous, and many animal species will hide their symptoms of ill health, a natural reflex to prevent them, attracting predator's attention in the wild. Large groups of intelligent animals such as primates often have complex social lives, and if animals are removed from their group for anything more than a few hours, can cause major social disruption and stress. When these patients are re-introduced to the group this can cause further stress, fighting and injuries. Other species can interfere with their wounds. Jaguars and other "big cats" can lick and bite their wounds open, and chimpanzees are notorious for pulling even buried stitches out, opening their wounds, and sticking dirty sticks into wounds, making infections a risk. All this makes managing a zoo animal surgery patient much more difficult, and emphasises the need for as minimally invasive surgery as possible, with the techniques holding the best likelihood of success.

Minimally invasive surgery  to remove a retained abdominal testicle (Laparoscopic cryptorchidectomy )in a Reindeer (Rangifer tarandus) at the Royal Zoological Society of Scotland.

One would imagine that surgery of wildlife in zoos is highly developed and of a similar standard to that performed in dogs and cats, but unfortunately this is unfortunately rarely the case. In some ways there has been little progress in zoo animal surgery over the last 20 years. While keyhole surgery has become the gold standard in many human surgical procedures, this is not the case in zoo animals. Despite the clear benefits of small wounds and rapid recovery from surgery, especially important in zoo animals, there are still only a handful of zoo vets able to perform these types of procedures in zoo animals worldwide. The majority of animals in a zoo are healthy, and so the need to perform complex surgery is very rare, and so it is almost impossible to build up a series of similar cases to be able to scientifically evaluate the best techniques, and the risk, complications, and success rates of a specific operation in a single zoo. All this is vital information that is needed in trying to judge the best course of treatment for a specific zoo patient. In contrast, domestic animal vets working with dogs, cats, horse, etc, have numerous scientific articles evaluating the majority of surgical techniques, and these may include over a hundred animals. Human surgical studies can include hundreds of thousands of patients in a study allowing the best pre-emptive evaluation of the pros and cons of a specific operation in a specific patient, and the optimal technique to perform this.

Surgical skills also have an important manual dexterity component, that many studies have shown is critical for success rates. Human and veterinary surgeons with the most surgical experience and largest cooperating case number generally have the best results, and the lowest risks of complications. As the vaste majority of zoo veterinarians only very occasionally perform complex surgery, perhaps only a few cases in a year, it is impossible to acquire these skills which are so vital to ensuring high rates of success.

So how does zoo animal surgery need to move forward in future? Zoo surgery needs to become "evidence-based", it needs the availability of specialist surgery skills, in additions to zoo veterinarians who have to do a bit of everything in their own zoos, and it needs to embrace and develop current trends in improving surgical outcomes and safety, currently underway in human surgery, from standardised protocols to minimally invasive surgical techniques.