A practice that solely treats ornamental fish? It’s already happened! Given the popularity of ornamental fish e.g., a minimum of 40 million in the UK, then it seems strange that there are not more. However, one needs to overcome you can’t treat fish. Fish keepers do require the same services as any other pet and as a veterinarian, you already have 90% of the skills necessary, so what is stopping you?

Virtually all the equipment and facilities you need can already be found within your practice. At most, you might want to invest in a fish anaesthetic machine, around $80 for a pump, reservoir tank and foam inserts, to $1000s for a real-time computer monitored model. Purchase a textbook, Fish Disease: Diagnosis and Treatment by E.J. Noga, around $120, you might like to join WAVMA (www.wavma.org) or visit the resources available from the University of Florida (http://tal.ifas.ufl.edu/resources-and-services/publications/). (VIN editor: Original link was modified on 1–24–2018). A children’s paddling pool, heater, and air pump can provide your fist hospitalization tank, maybe another $100, a water quality test kit ($50 to $1000s). For an investment of less than the price of some orthopaedic implants you have a fully functioning ornamental fish practice. However, there are some differences to be aware of.

Initial Marketing

Much the same as any other veterinary practice but remember people do not believe you can treat fish. Join or talk to any local aquarist clubs and post your services on social media. Something as mundane as removing a lump from a goldfish, can get you international exposure and even on TV.

Initial Contact

Receptionists need to be able to advise clients how to transport the fish, plastic bag, cardboard box, any need for oxygen, bring spare water (needed for the journey home and recovery from the anaesthetic), and a sample of water to test for water quality even if the client swears they do this routinely.

House visits can be more appropriate than a surgery visit, and receptionists need to be able to take a history and recognise when one might be necessary. Sudden death possibly suggests an environmental contaminant, lack of oxygen, or electrical fault. Chronic illness suggests possible stress and poor positioning of the tank or pond such as in full sunlight or excess vibration due to noise. All these are easier to ascertain as possible causes through a home visit.

The Consultation

Diary slots need to be for around 30 minutes. Take a history, check water quality, sedate the fish for skin scrape, gill snip, faecal sample, blood sampling, examine the samples under the microscope, and treatment. Time needed will decrease as you become more proficient.

It is acceptable to routinely use hobbyist test kits, where accuracy is needed such as in legal work then you need to use laboratory grade test kits or machines. Where possible, use a different test kit than the hobbyist as the results may well be different. Using gloves causes less damage to the mucous layer.

Charge for additional time as the system and the fish are relatively costly, fish such as koi or Arowanas can cost similar to or even more than expensive pedigree dogs. Fish are worth it.

Further Diagnostics

Skin scrapes should always be taken during the consultation with gill snips and faecal samples if necessary. Examine them as fresh as possible. Seeing the odd parasite per field of view should be expected but if numerous are seen then the fish has a problem. Blood samples can be run through blood biochemistry machines using standard rotas but check first with your supplier. Blood counts and PCV’s should be done manually as fish blood is “different” to mammalian blood. An obvious issue is that fish red blood cells are nucleated.

Fish are perfect candidates for ultrasonography as they arrive enclosed in the perfect conducting medium of water. Probes designed for ophthalmology use (e.g., 7.5 MHz) are most useful depending on the size of the fish. Good for getting “whole body” pictures, retrobulbar abscesses, swim bladder disease, and cardiology.

X-rays can be carried out under sedation/anaesthesia. Most fish will tolerate 5–10 minutes easily outside of water so long as they are kept moist. Useful to look at boney structures, the swim bladder, some tumours, but most internal organs are usually hard to differentiate.

To get true sampling for culture and sensitivity it is best to take the sample from the kidney. Requiring sacrifice of the fish and often not acceptable to the client. When swabbing an external ulcer, even if the sample is taken correctly, may not reveal the true cause. There are further issues which tend to mean you can end up with the incorrect information on the type of bug to the wrong sensitivity profile.

Surgery

There are some differences to fish surgery compared to mammals with the first being that fish need to be kept moist and for short procedures, a damp towel covering the fish’s eyes is suitable. (Note that towels and handling can damage the fish’s mucous layer.) Site preparation consists of a gentle wipe with sterile saline swab followed by one wipe of dilute povidone iodine swab. Traditional scrubbing damages the non-keratinised skin. It is acceptable to carry out no site preparation - think of fin snips - with no detrimental effects such as wound dehiscence or postop infection apparent. Traditionally scales should be removed (one or two rows) from the incision site otherwise delayed healing/postop infection may occur. This also provides easier placement of sutures so less iatrogenic trauma. However, current thinking is that this is not a necessity. If removing external masses healing will be by secondary intention.

To enter the coelomic cavity a ventral midline incision can be made posterior to the pelvic girdle (attachment of pelvic fins) ending anterior to the vent. The pelvic girdle can be incised and the incision extended anteriorly to the pectoral fins but the pelvic girdle may require wiring back together in larger fish. After the skin incision, blunt dissection with scissors of the musculature tends to decrease haemorrhage (remember fish blood volume is considerably less than mammals). Haemostasis must be good. If removing abdominal masses then no more than debulking may be achieved as delineation between tumour and normal tissue is difficult to determine without using CT or MRI scans. If the tumour is within the gonads then complete removal should be undertaken. Fish up to 12” in length can be sutured in a single layer using 4.0 nylon (preferred) or equivalent monofilament with a 12–16 mm cutting needle. Single interrupted, horizontal mattress or X mattress patterns can be used. Wound healing usually within 21–30 days (partly temperature dependent) and suture removal is preferable if possible.

Hospitalisation

Providing hospitalisation can be problematic as maintaining fish systems requires an actively working filtration system which needs time to mature. Stripping down and sterilizing the system between patients is not an option or having tanks empty between patients. Using a plastic paddling pool can be an option although it is labour intensive. Maintaining the system with a resident population to keep the filter ticking over can be useful although this means the filter is not routinely sterilized, the resident population may be at risk from infections, and still requires a lot of work to maintain making it expensive. One simple and effective solution is to do away with filters and replace them with trays of fast growing plants {think of aquaponics). Mature Busy Lizzie plants {Impatiens spp.) are cheap and effective. This removes the nitrogenous waste. At the end of a patient’s hospitalisation period they can be discarded leaving just the tanks and pipes to be sterilised.

Dispensing

Routinely used chemicals for the treatment of parasites such as potassium permanganate, malachite green, and formalin maybe better obtained by the client from the local aquatics shop. As perhaps will salt (a useful first aid treatment) and chloramine-T used either as a disinfectant or antiparasitic. Still leaving several veterinary endo/ectoparasiticides, aquatic disinfectants, antibiotics, NSAIDs that can be dispensed amongst the 300 or so drugs that are currently used in ornamental fish medicine.

Medications can be applied topically, by short dips, longer term baths, prolonged immersion, injection and in-feed. In selecting a medication thought should be given as to how it can be given. Most fish are inappetant when ill although using appetite stimulants can help. To minimize volumes, antibiotics should be given by injection and used as a last resort. As fish are poikilothermic treatment duration and frequency of repeat are affected by water temperature. Increasing the water temperature particularly in coldwater fish will improve immune function. It is also good practice to include supportive treatments along with the actual medication. Vitamin C and levamisole increase immune function, using a water disinfectant decreases pathogen load within the system and salt decreases osmotic stress.