Parasitological sampling of fish

Lesson 12

1. Read the words:

scalpel

microscopic

squash

similarly

alternatively

tissue

2. Master the active vocabulary:

parr - [ ] молодой лосось

stun - [ ] оглушать ударом

blow - [ ] удар

scraping - выскабливание

coverslip - покровное стекло

gross - [ ] большой, грубый; макроскопический

clip - [ ] скрепка, зажим, зажимать, сжимать,

3. Read and translate the text:

Step 1. Examination of skin: first stun the fish with a sharp blow to the head. Then take scrapings for microscopic examination using a scalpel and scrape from front to back of the fish or around the fins (Figure A). Place scraping on a clean glass slide with a drop of water from the holding facility and cover with a coverslip.

Step 2. Examination of gills: following gross examination of the gills, clip a small portion of gill lamellae with sharp scissors and place on glass slide (alternatively scrap the gill lamellae with a scalpel), add a drop of the holding tank water and cover with a coverslip. Examine under low power with high contrast or phase.

Step 3. Examination of other organs: any other organs suspected of having parasitic infection can have squash preparations made from small sub-samples of tissue and examined similarly using light microscopy.

Step 4. Record and/or draw your findings.

Figure A. Skin scrape of salmon parr using a scalpel.

4. Translate the following words and word combinations in writing.

1. a sharp blow - _________________________

2. a drop of water - _______________________

3. the holding facility - ____________________

4. a clean glass slide - _____________________

5. gill lamellae - __________________________

6. from front to back - _____________________

5. Translate into Russian using чем … тем …:

1. The more you learn, the more you know.

2. The more one studies nature, the better one knows its laws.

3. The better products, the better meal.

4. The sweeter water, the drier mouth.

5. The older the cow, the more time one need to cook it.

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