1. Stripping tools: scalpel, dissecting scissors, bone scissors, long tweezers (sharp, with no serrations in the front end), dissecting disk or plastic sheet, thin lead wire or bamboo chopsticks, brain spoon (take a piece of lead wire, and mash the front end into a spoon shape), needle, thread, cotton, bamboo wire, and preservative mixed with arsenic trioxide and alum.
2. Before measuring the specimen, it is an essential step to measure the relevant parts of the specimen, and only by obtaining accurate data can the species be better identified. Measuring tools and articles include steel tape measure, ruler, label and collection book. The contents of the measurement include the following items. Weight: the total weight of an animal's body; Body length: snout to anus, snout to tail base of large animals; Tail length: the length from tail root to tail end (except tail hair); Length of hind foot: from the last end of tarsal joint to the front end of foot (except claw), ungulates should measure the front end of hoof; Ear length: the length from the base to the top of the ear shell (except the tufts). Large mammals also need to measure shoulder height (from the midline of the shoulder back to the front fingertip), chest circumference (the maximum circumference of the chest behind the forelimb), waist circumference (the minimum circumference of the front waist of the hind limb) and hip height (from the midline of the hip back to the toe tip).
Step 3 make animal specimens
(1) Small mammal specimens can be divided into fake peeled 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 the back of a knife or tweezers to separate the skin and muscles connected with the hind limbs, respectively push the hind limbs out of the incision, cut the knee joint and remove the muscles on the calf, strip 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 palms facing down, the hind legs straight, the soles of the feet facing up, and the tail flat, and cotton should be picked up with tweezers to look 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.
(2) Specimen making of medium-sized mammals generally refers to rabbits, marmots, giant squirrels and weasels, such as weasels. The preparation method is basically the same as that of small mammals. Because this specimen is relatively large, the opening of the abdomen is slightly larger. When filling the body with bamboo filaments, a bamboo stick is needed to support the body.
(3) Specimen making of large mammals generally refers to tigers, leopards, wild boar, deer, etc. And there are generally two methods of making, ecological specimens and preserving skin and skull without filling prosthesis for scientific research. Taking this kind of specimen as an example, it can be made from the root of the tail to the snout and the inside of the limbs. However, when dealing with horned cloven-hoofed animals, it is necessary to open a "ya" mouth between the two horns and the back of the neck, and cut off the skin around the root of the horn; When the angle is large, it needs to be operated on the neck side. In addition, the hooves and claws of the limbs need to stay on the skin.
(4) Preparation of liquid immersion specimens of some small animals (such as bats and mice). ), this method can be used to prevent decay and alopecia, because the field work conditions can not be completed at one time, or because the purpose of classification can not be clearly seen after the specimen is dried, and because of the research needs of internal organs. The method is to soak the organs exposed from the abdominal opening with 75% alcohol solution or 5 ~ 10% formalin solution. Before soaking, each specimen should be tied with a numbered bamboo stick for easy reference.
(5) Preparation of bone specimens by insect erosion This method is suitable for preparing various bone specimens of vertebrates. Take animal specimens as an example. In the past, they were usually peeled and eviscerated first, then cooked with clear water, and then the muscles attached to bones were removed with tweezers. However, it was time-consuming and laborious, which easily damaged the specimens and affected their classification, identification and collection. In recent years, China has adopted the carnivorous habit of Coleoptera insect-dermatophyte larvae to remove muscles attached to bones, and achieved good results. Introduction is as follows.
① Morphology and insect origin
The body of the skin worm we use is oval, black or auburn, or patterned, with a body length of 2 ~12 mm; Larvae has segmented body and long hair. House dust mites are distributed in the north and south of China. They not only like to eat meat, but also bite books, clothes, rawhide sheets, medicinal materials and so on. When this method is carried out, it is necessary to collect and cultivate insect groups first, and it is best to collect midges in warm spring and summer. At this time, you can attract them with flesh and blood, or you can collect them in slaughterhouses where midges often move, stalls selling flesh and blood, and fur warehouses of animal husbandry companies.