By
Dennis Owusu Boateng
CSSVD CONTROL UNIT (GHANA COCOA BOARD)
Introduction
Care and handing of insect is just insect culturing which is generally the breeding of insects (beetle) for further use.
They can be use for experimental works, tourism and so on.
Sometimes hormones are also excreted from insects for preparation of cosmetics pomades etc.
Preparing Insect for Culturing
Apparatus
Insectarium
Media
Large Plastic or glass jar
Weighing scale
A tray of about 60mx60m
Glycerol
Insect culturing
Using beetle of cocoa as an example, the medium is prepared in the ratio of 8:1, which means eight parts of cocoa to 1 part of glycerol then the insects are then transferred to it.
It always difficult to start a new culture.
It has become possible for one to start a new culture from a sub-culture.
There are several ways of transferring insect from subculture.
Sub-culturing methods
This is the processes of preparing new culture from an old or exciting one.
There are several methods of sub-culturing.
These are stated below;
Paper transfer
Scoop or spoon transfer
Sieving transfer
Pan sorting
Use of topping
Paper transfer
The use of paper strips to transfer adult insects from an older stock jar to a new one is the quickest and easiest method.
Paper strips approximately 5" X 1" are used for sub-culturing pint and quart jars.
In a bottle with many beetles on the surface of the flour, put the paper strip into the mass of beetles, and wait for them to cover the bottom 1/4 - 1/3 of the strip.
Then quickly but carefully withdraw the strip from the first jar and insert it into the jar of new flour.
Shake the paper strip and tap it against the sides of the jar to remove the beetles.
Repeat the process until the desired number of beetles is transferred.
Discard that paper strip and use a fresh one for the next jar you subculture.
Scoop or spoon transfer
Use a small scoop or plastic spoon to collect adults from one jar or bottle and transfer to another.
"Sterilize" the scoop or spoon by rapping against the table top several times on both sides.
Tilt the bottle so adults move to one side to concentrate them for scooping.
Scoop carefully to prevent mashing any beetles against the side of the container.
Avoid scooping flour as much as possible. (You just want to collect live, healthy adults).
Again, it's a good idea to spot check each stock as you subculture it. Place about 10 adults in a "sterilized" Petri dish as mentioned above.
Avoid scooping flour as much as possible. (You just want to collect live, healthy adults).
Again, it's a good idea to spot check each stock as you subculture it. Place about 10 adults in a "sterilized" Petri dish as mentioned above.
Sieving transfer
When paper or scoop transfers are not possible, sieve and select live beetles for subculture by using the following protocol;
1. Bang sieves, receiving pans and aluminum sorting pans firmly and thoroughly on wastebasket lid immediately before and immediately after use. Bang the plastic transfer funnel lip sharply on the tabletop or wastebasket lid several times.
2. Inspect: Banged equipment visually for presence of clinging larvae or adults. If larvae are stuck in the sieve, try to dislodge by additional banging. If this fails, gently poke at them with a brush to encourage them to go on through or withdraw, whichever is the shorter route to getting out. Be careful not to damage them while they are caught in the sieve. If they bleed onto the sieve, their blood and body fluids will corrode the screen.
3. Sterilize brushes: Always sieve into a receiving pan, never onto the table top! Sieve any flour which contains larvae as quickly as possible, with continuous agitation dump siftings immediately into sorting pan to minimize the opportunity for larvae to try to crawl through screen and get stuck. For those caught in screen, dislodge first by banging sieve against receiving pan. Dislodge any remaining larvae by poking or "tickling" through screen gently with brush. Don't use lateral brushing action to dislodge stuck larvae --- rough treatment can squash larvae, and hemolymph from injured larvae can corrode screen of sieve. After sieving diseased stocks, wipe down the sieve and receiving pan with alcohol and dry completely.
Pan sorting (after sieving)
Adults
Count or sort the beetles collected in the aluminum pan by brushing adults into a Petri dish with a small to medium sized brush.
If your sample has a very large number of adults in it, flying beetles can be a problem.
You can minimize the problem by first putting all the collected beetles in one or more Petri dishes and place lids on the dishes.
Then return smaller portions of beetles to the aluminum pan for sorting a bit at a time.
Pupae
If collecting pupae from a jar with a spoon, you can exclude many adults by tilting the jar to one side.
Adults will move to the low side, and you can scoop from the center (Be sure to “sterilize" the spoon first by wiping off and rapping it against the table top several times on both sides!) .
Sieve, then brush adults and larvae into one petri dish, and brush pupae into another dish.
Diseased stocks
Diseased stocks should be sub-cultured every two days to dilute the disease organisms. Transfer only live beetles! Dead or moribund beetles should be discarded.
If a stock is not producing progeny
Are there any adults still alive? If there are live adults, check to see if they are all males (some disease seems to plug up and kill the females first). Is there evidence of disease . . . dead, dried, and sometimes darkened, larvae and pupae? ("Licorice stick" is a good description the of dead larvae's appearance. Dead pupae appear discolored and mummified, and are often chewed on by the adults.)
Are there mites in with the adults, or clinging to the adults? To differentiate between grain mites, psocids, and parasitic mites, you can look at this web pageto see what grain mites and psocids look like.
Parasitic mites tend to hang all over the adults, sometimes to the point of giving them a frosted look, and also hide under the wings and elytra. They seem to prefer female beetles, possibly as a way of being near eggs which they may feed on.
A permanent or long term cure is possible. Follow this link to view the section on parasitic mites in the "Disease & Mites" part of this guide.
Trouble Prevention
Keep all containers of beetles or culture flour closed or covered when not being used or worked with.
Bang pans and sieves up-side-down vigorously against wastebasket lid before and after each use to remove any remaining eggs or small larvae.
Wipe off and rap spoons and scoops against table top before each use.
"Squeegee", sterilize brushes before each use.
If beetle adults, larvae or pupae are found on the table top as a result of sieving, discard unless you saw it fall and are 100% certain of its origin.
Don't house beetles in airtight containers, and don't push corks tightly into mouths of vials. Insects need fresh air!
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