When novel coronavirus pneumonia sweeps the globe, it is well known that the virus sampling tube is used routinely in our daily inspection and prevention. In many diseases, many infectious diseases are not obvious. Clinical experience alone is difficult to diagnose accurately and to use drugs accurately, which often leads to the illness. Therefore, it is necessary to take disease materials from sick animals or corpses with virus sampling tubes, further conduct microbiological and serological tests, find out the pathogens, and then take corresponding prevention and control measures, so as to achieve the purpose of preventing, controlling and extinguishing infectious diseases, reduce the blindness of clinical work, improve the technical level of veterinary personnel and protect the interests of farmers. Whether the methods of collecting, storing and sending sick materials for inspection are correct directly affects the inspection results and the development of prevention and control work. Therefore, collecting and testing samples is an important content of diagnostic testing. In addition, whether the sampling time is appropriate, whether the samples are representative, and whether the sample processing, storage and transportation are timely will affect the accuracy and reliability of the test results.

The following summarizes and arranges how to correctly collect, preserve and send sick materials for examination, hoping to provide some reference for grass-roots veterinarians and farmers.

1、 Collection principle

1. Fresh, representative and sufficient: collect dead poultry samples within 6 hours in summer and 24 hours in winter: the number of samples collected shall meet the needs of diagnosis and testing, and leave room for re inspection if necessary.

2. Reduce the pollution of diseased materials: during autopsy, the corpse should be soaked in disinfectant solution to prevent the pollution of feathers and dandruff to diseased materials; During the collection of sick materials, the instruments and containers for collecting sick materials must be disinfected in advance to reduce the pollution of the instruments or containers containing sick materials to the sick materials: when the abdominal cavity of the corpse is opened, the sampling tube takes the sick materials at one time to reduce the pollution caused by the exposure of the sick materials to the air.

3. Typical sampling: select the samples without drug treatment, with the most typical symptoms or the most obvious lesions. In case of complications, sampling should also be considered.

4. Reasonable sampling: according to the requirements of diagnostic testing, a sufficient number of samples must be collected in strict accordance with the regulations. In addition, the samples to be tested for different epidemics are different, and the sampling shall be focused on the possible epidemics. For those who cannot determine what kind of epidemic disease, comprehensive sampling shall be carried out.

5. Safe sampling: not only protect the sampling personnel to prevent the leakage of pathogens, but also prevent the samples from being polluted.

6. Rapid inspection: it shall be sent to the laboratory for inspection as soon as possible. Delaying the inspection time will affect the inspection quality and the reliability of the results.

2、 Collection method of disease materials

1. Collection of tissues and parenchymal organs: after opening the abdominal cavity, attention must be paid to the integrity of the intestinal canal. If it is necessary to isolate and culture bacteria, scald the organ surface with a red burning surgical blade, insert the flame sterilized inoculation needle into the scalded part, extract a small amount of tissue or liquid, conduct smear microscopic examination or inoculate it on the culture medium for culture.

2. Collection of liquid diseased materials: collect liquid diseased materials such as blood, bile, abscess fluid and exudate, use sterile straw or syringe to absorb the liquid of diseased tissue through the scalding part, inject the diseased materials into the sterilized test tube, plug the cotton plug and send it for examination.

3. Whole blood collection method: take 2-5ml blood from the chicken heart or wing vein with a sterilized syringe and inject it into a sterilized test tube. It is recommended to add a small amount of anticoagulant (3.8% sodium citrate 0.1-0.5ml or sodium citrate solution, preparation method: glucose 2.05g, sodium citrate 0.8g, citric acid 0.055g and sodium chloride 0.42g, add distilled water to 100mi, autoclave for 10 pounds and 80 minutes.)

4. Serum collection method: take 2ml of blood from the heart or wing vein of the bird with a sterilized syringe, inject it into the sterilized 1.5m1 centrifuge tube and place it into an inclined plane. After the blood coagulates and the serum precipitates, suck out the serum and inject it into another sterilized test tube for standby.

5. Collection method of intestines and intestinal contents: select the intestines with obvious lesions, discard the contents, rinse them with sterilized normal saline, and then put the sick materials into sterilized 30% glycerol saline buffer for examination. You can also cut the intestinal canal, wash it with sterilized normal saline, burn the mucosal surface with a red burning surgical blade, insert the inoculation needle into the mucosal layer, and take a small amount of disease material to inoculate on the culture medium. To collect intestinal contents, burn the serosa layer of the intestine with a red burning surgical blade, insert the inoculation needle into the intestine, absorb a small amount of intestinal contents, put them into a test tube, or tie the two ends of the intestine with intestinal contents tightly, remove other parts and submit them for examination.

6. Collection of skin and feathers: select the edge of the obvious part of the skin and put a little into the sterilized virus sampling tube for examination; Feather should also select the part with obvious lesions, scrape a small amount of feather and root dander with a sterilized blade, and put it into a sterilized test tube for inspection: collect the fluff in the incubator, use sterilized tweezers to take 3-5g of fluff from the air outlet of the brood machine, and put it into a sterilized test tube for inspection.