【Animal Modeling】-Non-infectious fever model

  (1) Model of fever caused by turpentine or 2,4-dinitrophenol

  1. Modeling material animal: rabbit; drug: turpentine or 2,4-dinitrophenol, saline, ethanol, 5 mol/LaOH solution.

  2. Modeling method: inject 0.4 ml/kg turpentine or 2% 2,4-dinitrophenol ethanol solution (or aqueous solution, 150 mg 2,4-dinitrophenol) into 80 ml brine, and add 5 mol/ L. Add NaOH solution dropwise to the salt solution, drop it until the drug solution becomes clear and bright yellow, and continue to stir, and then add 100 ml of conventional salt solution to 15-30 mg/kg.

  3. Modeling principle Turpentine or 2,4-dinitrophenol can cause fever in animals.

  4. Changes after model construction Within 18-20 hours after injection of turpentine, the animal caused fever, which reached a peak in about 24-36 hours, and increased at a temperature of 1.5-2.0°C for 2 days. After injection, start 15 times of 2,4-dinitrophenol heat at about 20 minutes, reach a peak in 1-1.5 hours, and increase by 2-3°C.

  (2) Carrageenan-induced fever model

  1. Modeling material animal: rat; drug: carrageenan, saline or distilled water.

  2. Modeling method Inject 1% carrageenan suspension subcutaneously into each hind leg of the rat (accurately weigh 100 mg carrageenan in a test tube, add sterile saline or distilled water to 10 ml, lightly Stir gently and place in the refrigerator overnight). 4°C, take out the next morning and gently invert several times to homogenize the suspension) 0.1 ml/tablet.

  3. Modeling principle Carrageenan can heat animals.

  4. Changes after modeling The body temperature of animals usually starts to rise 4 hours after carrageenan injection, reaches a peak at 6-7 hours, and continues for more than 10 hours.

  (3) Fever model induced by heterosexual protein

  1. Modeling material animal: rabbit; medicine: protein ept or skimmed milk. 2. Modeling method: intramuscular injection of 1.0 g/kg of 10% protein ept or 3-5 ml of sterile skim milk was injected subcutaneously into the rabbit.

  3. Modeling principle Heterosexual protein can cause fever in animals.

  4. Changes after modeling After the injection of protein ept, the animal's body temperature increased significantly within a few hours. After injecting milk, the body temperature usually rises by 1.0 to 1.5°C after 3 hours.

  (4) Fever caused by warm puncture

  1. Modeling material animal: rabbit; drug: anesthesia.

  2. The modeling method is to anesthetize the animal, measure the rectal temperature of a normal rabbit, make a 3-4 cm incision in the skin along the midline of the rabbit's skull, and connect the sagittal and coronary sutures. Hole in the skull. Insert the thick needle vertically into the hole and pierce it straight into the bottom of the skull. After the occipital process, a puncture can also be performed 1.5-2 cm to the right of the midline connected to the upper edge of the orbit.

  3. Modeling principle stimulates nerves and heats animals.

  4. Changes after modeling Mechanical stimulation of the thalamus can cause a significant increase in body temperature, which lasts for several days in 2-4 hours. In the latter method, the body temperature rises immediately after the puncture.

  (5) Classical swine fever model

  1. Modeling materials Animals: Landrace pigs, York × Landrace binary hybrid pigs, approximately Gram × Landrace × Duroc Turnary hybrid pigs, 1-2 months old, weighing 15? 35 kg; medicine: skimmed milk.

  2. Modeling method The healthy control group was not injected with any drugs. The blank control group was injected with 2 ml saline per kilogram of body weight. Another group of experimental pigs were injected subcutaneously with 1-3ml. /kg Increase the body temperature of defatted and disinfected milk pigs.

  3. Modeling principle Heterosexual protein can cause fever in animals.

  4. Changes after modeling The body temperature of most experimental pigs increased 2 hours after being injected with skim milk, reached a peak at 4 hours, maintained for 2-6 hours, and then slowly decreased. Indicates a long-term heating type of up to 28 to 32 hours, which can maintain a high temperature of 40°C or higher. After the body temperature rises, pigs show signs of high fever, such as thirst, irritability, loss of appetite, flushing of the eyes and conjunctiva, irritability and lethargy.

  5. Note that pigs show a stable response to changes in the external environment, and the exothermic response is relatively stable, regardless of age (weight) or breed. This is the ideal laboratory animal model for fever. Before establishing a fever model to select the appropriate dose, the dose selection can be tested in advance. When choosing the weight of experimental pigs, a weight range of 20-25 kg is appropriate, because too light weight will reduce the resistance to fever, and too much weight will cause difficulties for experimental animals.