A common parasite As with many fish parasites, small numbers of Costia (or more correctly Ichthyobodo) are not uncommon and appear not be detrimental to the fish’s health. In small numbers these parasites seem to live on cellular debris in a commensalistic relationship with their fish host. Costia occasionally live on the skin and gills of healthy fish and it ..
Even one parasite warrants immediate action The parasite Chilodonella is a major threat to fish health and finding even one parasite warrants immediate treatment. Chilodonella is a potentially dangerous parasite for two reasons. First, unlike many parasites, it has a wide range of temperature tolerance and outbreaks often occur at low temperatures when fish are least able to resist. ..
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Practice make perfect Although the microscope is a fairly simple instrument to set up and use, interpreting what you see can sometimes be difficult. It really requires practice until such times as you know what is normal and what is not. As a piece of advice I would suggest familiarizing yourself with healthy or non-urgent ..
Setting up The most common cause of disappointing results is poor setting up of the microscope before use. The performance of almost all microscopes can be improved if a little time is spent focusing before use. No matter what quality microscope you buy, it makes sense to get the best possible image it is capable ..
General microscopy For general microscope work, a magnification between 40X and 400X is usually sufficient and will allow for relatively easy identification of most common ectoparasites. Higher magnification When talking about higher magnification it is important to understand the difference between simply magnifying the size and increasing the amount of visible detail. With high-power microscopy ..
A sequence of steps to take There is a clear sequence of steps to take to achieve perfect viewing. These are detailed in the box below. A word of warning: Take care when adjusting the focus knobs that you do not advance the objective lens onto the slide! It is very easy to break the ..
Specimen needs to be as thin as possible Before any specimen can be examined under the microscope, a slide has to be prepared. No matter how good your microscope is, the final image can only be as good as the slide you are viewing, so proper preparation is important. A normal compound microscope works by ..
An essential piece of equipment Without a microscope it is simply impossible to tell the difference between a water quality and a parasite problem. The microscope should be considered the most basic of tools in fish disease diagnosis – indeed, an accurate, full diagnosis of the disease and its cause just isn’t possible without a microscope!! ..
When a condition is untreatable As with all other animals, there are situations when the fish, for a variety of reasons, either fails to respond to treatment or has a condition that is untreatable. It is my belief that fish are capable of suffering and therefore the most humane act in such a situation is ..
