SN/T 1420-2004Protocol of diagnosis for whirling disease (English PDF)

2.1 Equipment

Ordinary balance, analytical balance, general centrifuge, micro-oscillator, water bath, oscillating water bath, ordinary microscope, hemocytometer, pH test Paper, mortar, scalpel, tweezers, beakers, slides, centrifuge tubes, adjustable pipettes, etc.

2.2 Reagents

Bleaching powder, 10% formalin, 1% malachite green, 70%, 80%, 90%, 95%, 100% alcohol, xylene, Giemsa staining solution (see attached Record A), pepsin solution (0.5%) (see Appendix A), casein solution (0.1%) (see Appendix A), 0.1 mol/L sodium hydroxide, 10% cattle Serum protein, phosphate buffered saline (PBS) (see Appendix A), methanol, acetone. All chemical reagents were of analytical grade.

3.1 Clinical symptoms

The diseased fish is in a frantic rear-end campaign, especially when fed or frightened. In cold water conditions, the clinical manifestations of rotational motion are usually it occurs 2 to 3 months after infection and can last up to one year. Diseased fish from 2 months to 8 months old with black at the back and tail of the trunk. faint in the late stage of the erythema, the diseased fish sacral atrophy, the sputum is exposed, the mandible is deformed, the spine is curved, and the skull behind the eye is severely sunken.

It still carries pathogens after the year.

3.2 Parasitic examination

3.2.1 Pathogen morphology

(7.5µm~8µm), micro-ovate, flanked by small lentils; there are two pear-shaped capsules, two round embryo nucleus in the spore, a seamless ridge Visible suture, no iodine foam (see Appendix B).

3.2.2 Sampling

3.2.2.1 Sampling principle

Select a clinically symptomatic fish for parasite examination. If it is asymptomatic, it can be randomly sampled according to the number of fish.

3.2.2.2 Number of samples

Take 5 to 10 tails for symptomatic fish for parasite examination, or for asymptomatic fish group according to Table C. 1 Conduct a spot check.

3.2.3 Smear inspection

3.2.3.1 Cut the head longitudinally and observe the presence or absence of cysts (milk-white, 1 mm to 2 mm in diameter) in the cartilage tissue of the ear region.

3.2.3.2 If there is a cyst, take a small cyst on a glass slide, crush it, and check it with a microscope from 450 to 600 times to see if there is a brain.

Sticky spores.

3.2.3.3 If no cysts are found, the cartilage tissue is cut from the otolith area and the contents are scraped for smear examination. Both the left and right ear stone areas need an examination.

3.2.3.4 No spores were found in the above two tests, which can be checked according to 3.2.4.

3.2.4 Smear staining check

3.2.4.1 Cut the head of the suspect fish and cut it longitudinally, incubate in 45 ° C water for 1 min to 3 min, and move the loose meat and brain to a waste capacity.