P. 170

An Urban Experience
protozoa). But enteric infections with bacteria such as Pseudomonas can also present in a similar fashion.
The common term of ‘dropsy’ is used when there is
also protrusion of the scales to create a ‘pine cone’ appearance due to subcutaneous edema. This is obvious in  sh with larger scales, but is dif cult to appreciate in species such as the angel sh with  ne scales. Dropsy
is often accompanied by ‘pop-eye’ (exophthalmia). These are commonly a result of primary or secondary bacterial infections causing in ammation and vascular damage, especially to the rich vascular beds in the kidney and choroid rete behind the eye. The insult to the kidney interferes with  uid balance, causing the ‘dropsy’ appearance and in ammation behind the eye causes the ‘pop-eye’ appearance. There is one breed of gold sh where exophthalmia is selected and these are known as telescope moors.
Fish in advanced disease can present with buoyancy disorders. They may either become negatively buoyant and sink to the tank  oor, or become positively buoyant,  oating to the surface. This is a very common condition in gold sh breeds and in my experience, it is more common in rotund breeds such as the ryukin, pearl scale and orandas. These  sh tend to also have twin tails. There is suggestion that  sh should not be overfed and that they should be given adequate  ber in their diet. Systemic bacterial infections are also common causes
of buoyancy disorders. Less common causes include coccidial and fungal infections of the swim bladder.
Fish that are wasting present with concave abdomen. The differential diagnoses for poor body condition in  shes include, but are not con ned to the following: chronic malnutrition, or infections by bacteria (e.g. mycobacteriosis), protozoal organisms (e.g. Hexamita, Spironucleus, Cryptobia, Sporozoa, Ichthyobodo) and metazoa (e.g. Gyrodactylus, Dactylogyrus and a number of cestode species). Fish with enteropathy will have long fecal strings, that may contain bubbles and  oat, or they may be empty fecal strings (in most freshwater  shes, normal fecal casts should resemble black string). If they are overfed, their fecal strings take on the same color
of the  sh food fed to them. Those with enteritis will display congested vents. This can be overlooked when assessing health of pond  sh. Thus it is very important to capture some  sh to examine their vents.
Causes for sudden death are dif cult to diagnose because  sh tissues autolyse rapidly. Based on epidemiological principles, sudden death is likely due to environmental causes. Collating a good history and water quality analyses are important.
Inappetance is a non-speci c sign of illness. It can
also occur when water temperature deviates from their tolerance range. The most common is during winter when owners are unaware that they need heating for their Siamese  ghting  sh, or their heater has stopped working. You will see remains of uneaten food in the tank or  lter.
So we have discussed the clinical signs displayed by  sh during ill-health. But some other things we should also consider include their environment. Fish that are sick tend to produce more mucus and you may notice a  shy smell coming from the tank and perhaps there may be excess stable foam accumulating at the water surface.

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