Preparation of animal specimens

(1) Small mammal specimens can be divided into fake skinned specimens for scientific research and ecological specimens for teaching and exhibition.

① Pseudodissection specimen (taking rats as an example)

fruit peel

Put the mouse on the dissecting disc and plastic cloth, and cut the skin along the front of anus in the middle of abdomen to the back of sternum with a scalpel. Don't use too much force during the operation, so as not to cut the abdominal cavity and pollute the fur. Then use a knife back or tweezers to separate the skin and muscles connected with the incision and hind limbs, respectively push the hind limbs out of the incision, cut the knee joint and remove the muscles on the calf, peel off the muscles around the back, and then cut off the joint of genitalia, rectum and skin. Clean up the connective tissue around the caudal base, hold the caudal base tightly with your left hand, and slowly pull the caudal vertebra upward with your right hand until it is completely pulled out, then peel it off to the forelimb, cut it off at the elbow joint, remove the muscle and peel it off to the head, and use a scalpel to cling to the skull to the ear. When you cut or cut off the ear root to the eye, you can see a layer of white omentum-like eyelid margin, and after carefully cutting the lower end of the omentum, your eyes will be exposed. When peeling off the upper and lower lips, first cut off the cartilage at the tip of the nose, and then peel off the lower lip with a scalpel. At this point, the skin and the body have been separated, the fat in the skin and the muscles attached to the skin are removed, the antiseptic is evenly coated, a little cotton is wrapped around the bones of the limbs to replace the original muscles, and then the mouse skin is turned over to form a straight tube with the skin facing outwards.

fill up

The 1 bamboo, which is slightly thinner and smoother than the original coccyx, is used to fake the coccyx, or lead wire is tightly wrapped around cotton to make a dummy tail, which is inserted into the tail of rats, and the dummy tail is longer than the original tail, reaching the abdominal cavity 1/2, so that the tail is fixed and the whole body is supported. Then, the fluffy cotton is kneaded into a shape that is thin at the front and thick at the back, the front end of the cotton is clamped with big tweezers, and then it is tightly inserted into the head from the opening, and then the fluffy cotton is properly filled in the insufficient parts of limbs and trunk. At this point, the cut coccyx should be close to the cotton in the abdomen, so that the coccyx does not become warped. When sewing the incision, the specimen should be put straight and the needle should be sewn from the inside out.

Plastics and fixing

The quality of specimen making has a great relationship with plastic surgery. During plastic surgery, the specimen should be placed horizontally on the table, with the head facing left, the front legs retracted, the palm side down, the hind legs straight, the sole side up, and the tail flat. Use tweezers to pick up cotton in the eyes, which looks like a slightly convex eyeball. Hair should be neat, ears should be upright, head should be slightly pointed and hips should be arched. The label is attached to the right foot, the specimen is placed on the fixing plate, and the limbs are fixed with pins. After drying in the shade, the fake peeled specimen was made. (2) The ecological specimens of museums, teaching and other units often make animal specimens into life postures for popular science. The method of stripping is basically the same as that of pseudo-stripping specimens. When filling, only lead wire (steel bar or steel plate for large animals) is needed to support its limbs. The type of lead wire used depends on the size of the animal itself. The head, limbs and tail are supported by 1 wire respectively. The lead wire of the head is first rolled with cotton into the same thickness and length as the original muscle of the neck, and one end is fixed on the skull. You can also keep the original skull. In addition, the 1 lead was inserted into the limb from the sole of the foot along the posterior side of the limb bone, leaving a section for fixation. Lead wire is bent along the bones of the limbs and tied to the bones with thread. It is still necessary to add cotton to the limbs to replace the original muscles. The coccyx should not be made of bamboo, but must be made of lead wire in various postures.