Birds are the only animals with feathers and scales. Their scales in their feet indicate their ancestral link to reptiles. Feathers are modified scales, being non living outgrowth of certain skin cells. Examples of these non living outgrowths are the human hair and fingernails.
There are two kinds of feathers foe birds. The contour feathers that cloth their bodies and provide their flying surfaces, and the other one is the down feathers which characterize young birds and sometimes, underline the contour feathers of the adults. Both types of feathers can make interesting preparations and will make great a great study with the microscope. Best source for feathers are pet shops, a pillow factory, or a chicken farm.
However, feather mites on poultry and chicken farms are widespread and maybe contagious. Birds feathers should regularly be checked with feather mites. Detection of feathers mites are done by examining the feather under the microscope. Feather mites can be accurately detected under a stereomicroscope on living as well as the dead birds. Each microscope examination is concluded with the determination of the species. Feather mites are naturally microscopic and cannot be seen without the aid of the microscope.
If the feather mites are situated on the radii, they can be seen as little dots on dark feathers and therefore the microscope is needed to examine this type of infestation. Microscope is also essential in examining minor infestation and smaller feather mites. The exact diagnosis is carried out through microscopic mite detection.
When studied under a microscope, you will find out that birds feathers have many interesting features. The long central shaft of the contour feathers carries many parallel side branches, the barbs. These barbs cling together in the flat sheets known as vane in order that the feather will be stiff enough to beat against the air when flying. The barbs are also equipped with the barbules or the multitude of tiny hooks. These barbules interlock tightly with each other to set the barbs into the form of the vane. Place a contour feather on a microscope glass slide, examine it and notice the way in which the barbules interlock to form the vanes.
The feathers in the bottom parts of the birds lack the stiff central shaft called the quill of the contour feather and they are nothing more than tiny puffs of long, slender, fluffy strands of feathers. The down feathers are excellent insulating material as the loose, wooly barbs trap and hold air that is the most effective and excellent insulator. Pure down feathers make the very best sleeping bags and outdoor garments. Permanent mount of feathers are very simple to make. Specimen is immerse in xylol for five minutes and after that, it is remove and will be allowed to drain. Then the feather is mounted into a drop of balsam on a microscope glass slide and then capped with a cover slip.
Specimens that mostly make great mounts are fish scales. This specimen is also very easy to mount on the microscope glass slide. Probably, most people are aware that the age of a tree can be determined through counting the growth rings in the sawed section of the trunk. The same information can also be revealed by the scales of many fishes because they also exhibit similar type of growth rings. These concentric rings are formed as the scales of the fish increases in diameter with the age of the fish. During periods of slow winter, these rings are crowded together and are wider in space as a result of more rapid summer growth. It is possible to estimate the age of fish by counting its seasonal growth rings underneath a microscope.
Two types of scales are commonly found in fishes, in general. Some fish lack scales altogether, many eels for example, but the scales are usually cycloid or ctenoid among the bony fishes. The cycloid scales are finely toothed like a comb along one margin. By immersing the scales in xylol or oil of gloves for ten minutes, the microscopist can be able to prepare mounts for both types. Allow the scales to drain dry and then mount them in balsam on the microscope glass slide.
