When Doing Microscopy on Koi.....

[adreamer2]

What magnification would you suggest to study the effects of bacterial infections?......

I'm trying to determine what kind of microscope to purchase.... Just trying to get it before Spring arrives.... hehehee

I was looking at a microscope with the magnifications of: 100, 450, and 900 mag lenses.....


Adreamer2

[Charlie_23456]

Quote: Originally Posted by adreamer2 What magnification would you suggest to study the effects of bacterial infections?...... I was looking at a microscope with the magnifications of: 100, 450, and 900 mag lenses..... Adreamer2

Hi Adreamer2,

A microscope that gives you magnifications of 100X - 900X would be sufficient for any Koi microscopy needs. From those numbers I would assume that there are three objectives on a rotating turrent, one each of 10X, 45X and 90X with 10X oculars. Study of the bacteria itself would be very hard to do for the average person because it would require culturing and staining. Most Koi microscopy is done to identify parasites...flukes, fish lice, anchor worms, costia, chilodonella, Trichodina, Ick, etc. In the case of parasites the most common objectives used would be the 10X and 45X...depending on the size of the parasite.

A good microscope should have excellent optics (good quality glass rather than plastic), good lighting with a good quality condenser (condenser is under the stage and regulates the amount of light reaching the objectives). Also make sure it has a mechanical stage and not just stage clips. A mechanical stage lets you move the slide with the specimen in a x-y axis by turning knobs, where as the stage clips keep the slide stationary and you need to move the speciment by hand moving the slide around. Another option is whether the scope is monocular or binocular...single eye piece or two. The binocular is more comfortable when viewing specimens but costs more.

If you're not sure of what you are seeing in the microscope, a USB viewer that slides into one of the oculars so pictures can be taken or specimens can be viewed and saved on your computer can be a very useful tool.

[butterfly]

Quote: Originally Posted by adreamer2 What magnification would you suggest to study the effects of bacterial infections?...... I'm trying to determine what kind of microscope to purchase.... Just trying to get it before Spring arrives.... hehehee I was looking at a microscope with the magnifications of: 100, 450, and 900 mag lenses..... Adreamer2

You should start with 100x and go to 900x. At 100x adjust the field, cotrast light etc. then move to higher. At high resolution, you should see them as small specs almost indistinguishable from dust particles. However, if it is a bacterium it will move around and you will be able to identify from their movement. That is if the slide is fresh and the bacteria still alive. Second, you should look at multiple fields and see whether you see the bacteria or moving specs in large numbers. Many bacteria has flagella or moving tails. You may or may not see that in your magnification.

[Charlie_23456]

Actually...Bacteria are identified by whether they are 'rods' or 'spheres' and some are 'spiral'... whether they are gram positive or gram negative...whether they are single, in pairs or chains...hence you would need to culture/stained them for identification. You would also view them, after they have been prepped, with an oil immersion objective.

Although you can see bacteria 'vibrating', the critters that are moving around and have flagella and or cillia are usually unicellular organisms...protozoa...and are not bacteria...but are the critters that you are interested in identifying, i.e. costia, chilodonella etc.

[Rich L]

If you are looking for a microscope to treat koi, you will be using it mostly for parasites.

I use 40 power for larger parasites (flukes, etc.) and 100 & 400. 100 is a little low for costia, particularly with one of the less expensive scopes so 2 or 400 will work with smaller bugs like costia.

Most scopes we use have a 10X single or pair of eyepeices and 4, 10, 400 objectives. My scopes have always had a 100X objective to provide 1000X magnification (100 X 10). I seldom use it and then only for my own amusement. It's not of much value for our routine use.

As to single or binocular, A single eyepiece is as good as any unless you will be using the microscope for extended periods. Then the binocular eyepieces are more comfortable. It's also easier to sell the one with the pair as well.

There should be a mechanical stage with an adjustable slide holder.