Key Points and Detailed Operation Methods of Antler Harvesting Techniques

Velvet antler is the unossified young horn growing on the forehead of male deer, possessing multiple pharmacological effects and is a precious traditional Chinese medicine. There are many species of cervids, but the Chinese Pharmacopoeia recognizes only sika deer velvet and red deer velvet. Timely harvesting of velvet antler is an important part of the production process for @#@253@#@ farms (households), directly affecting the economic benefits of deer production. The author of this article introduces the velvet harvesting techniques for sika deer and red deer. According to different specifications required for velvet harvesting, the harvested velvet antler includes sika deer's two-branch velvet, three-branch velvet's cut-head velvet and sawed velvet, and red deer's three-branch velvet, four-branch velvet's cut-head velvet and pot velvet. According to different restraint methods used during velvet harvesting, they can be divided into mechanical restraint and drug restraint (the combined mechanical and drug restraint method is rarely used in practice).

I. Preparations Before Velvet Harvesting 1. Personnel Preparation Professional deer farms generally form a velvet harvesting and inspection team composed of the deputy farm director in charge of production, the velvet processing team leader, the deer team leader, technicians, and experienced processing personnel. They observe the velvet growth situation on the farm daily, having a clear understanding of the harvesting timing so as to harvest at the appropriate time. 2. Equipment and Supplies Preparation Farms (households) using the mechanical restraint method for velvet harvesting should conduct a comprehensive overhaul of the semi-automatic splint-type restraint device (hanging pen) on the farm to ensure it is in normal working condition. Prepare velvet saws, anesthetics, hemostatic drugs, technical training for velvet processing personnel, and equipment needed for velvet processing. 3. Mastering the Accurate Timing of Velvet Harvesting The velvet harvesting specification should be determined based on market demand information, while also considering velvet yield. Two-branch velvet is expensive but has low yield; three-branch velvet, although lower in price than two-branch velvet, has high yield. Therefore, when harvesting velvet, while considering market demand, one should comprehensively consider the growth and yield of the velvet antler to decide whether to harvest two-branch velvet or three-branch velvet. For sika deer at the first sawing, two-branch velvet is mainly harvested; at the second sawing, two-branch velvet is generally harvested, but if a sika deer at the first sawing can produce two-branch velvet with a fresh weight of 0.5kg or more, the second sawing can consider harvesting three-branch velvet. Male deer at the third sawing and beyond mainly harvest three-branch velvet. Red deer generally do not harvest red deer lotus velvet (equivalent to sika deer's two-branch), mainly harvesting three-branch velvet; for individual velvet with good growth and vigorous development, four-branch velvet can be considered. When harvesting velvet, pay attention to observing the mouth tip and root condition of the velvet. If the velvet's mouth tip is thick, plump and tender, with vigorous growth and the velvet root does not show cucumber-shaped or wart melon skin morphology, large mouth-tip velvet can be considered; otherwise, small mouth-tip velvet should be harvested.

II. Restraint of Deer The restraint methods for deer are mainly mechanical restraint and drug restraint, while the combined mechanical and drug restraint method is not widely used in actual on-site velvet harvesting. 1. Mechanical Restraint The main equipment for mechanical restraint is the semi-automatic splint-type restraint device (hanging pen), which consists of a passage connected to the pen and the restraint device. The passage has multiple gates and a disc-type revolving door. When deer are directed into the passage, these structures can push the deer to be sawed into the restraint device for restraint. Completing these tasks requires 9 people. 2. Drug Restraint The drug restraint method mainly uses anesthetics to anesthetize the deer, putting the deer to be sawed into a comatose state to achieve the purpose of restraint. There are mainly two commonly used anesthetics in the drug restraint velvet sawing process, namely succinylcholine and Miannaining. Succinylcholine anesthesia restraint. The use of succinylcholine (succinylcholine chloride) began abroad in the mid-1950s. Because the effective immobilizing dose of this drug is very close to the toxic dose, poisoning is very likely to occur, causing death of deer during anesthesia. The following points should be noted when using succinylcholine anesthesia restraint. Before administration, estimate the deer's body weight (sika deer 0.07-0.10mg/kg, red deer 0.065-0.09mg/kg), accurately determine the dosage, preferably use the optimal dose at once, and absolutely avoid administering a supplemental injection after insufficient dosage, to prevent anesthetic poisoning. Before administration, calm the deer herd to prevent deer from panicking and running around, causing adverse reactions or even breaking the velvet antler. The best injection sites are the deer's neck and arm to promote rapid drug absorption. When the deer falls, promptly have someone secure the head to prevent injury to the velvet antler, while laying the deer on its side in a cool place. To prevent excessive bleeding during sawing, elevate the deer's head. Do not saw the velvet immediately after the deer falls; observe until the deer's heartbeat accelerates and blood circulation is vigorous, then saw before the deer is about to regain consciousness, and pay attention to hemostasis. After the deer is anesthetized and falls, observe changes in the tongue, eyes, and breathing to prevent poisoning and death. Miannaining anesthesia restraint. Miannaining is a recently developed special immobilizing agent for cervids (sika deer 1.5-2.0ml/100kg, red deer 1.2-1.5ml/100kg). It has fast anesthesia speed and has antagonistic antidotes Huisuling No. 3 and No. 4. It is currently widely used, safe and effective, but the following points should be noted when using it: 1. Contraindicated for those with severe parenchymal organ lesions, after satiation, or still in an excited state after vigorous exercise. 2. When used under fasting conditions, the deer's head and neck should be elevated to prevent rumen contents from overflowing and being aspirated into the lungs. 3. When used in high-temperature seasons, antidotes should be available as a safety guarantee; under severe cold conditions, deer have increased tolerance to this drug. 4. This drug has strong effects; strictly prohibit misuse in humans. 5. This drug is a chemical restraint agent and should be strictly managed and used by professionals, with attention to theft prevention and illegal use.

III. Velvet Sawing Techniques 1. Velvet Sawing Time Since the entire velvet harvesting season is in midsummer, after inspecting the deer to be harvested on the evening of the previous day, saw the velvet early the next morning before morning feeding. At this time the deer are fasting, the environment is quiet, which facilitates the recovery of the sawed deer and the processing, preservation, and drying of the velvet after sawing. 2. Velvet Sawing Location After the deer is restrained, use a specially made velvet saw to cut at 1.5-2.0cm above the pearl disc. The sawing plane should be parallel to the pearl disc. Never damage the antler base, which would destroy the foundation for antler growth. The sawed velvet antler, after weighing and registration, is sent to the processing room for processing. 3. Hemostasis Hemostatic drugs. Commonly used hemostatic drugs are: (1) Qili San and zinc chloride in equal parts, mixed evenly and ground into powder for. (2) Qili San and dried fried loess ground into powder for use. Hemostasis method: Divide the hemostatic powder evenly into portions on thick paper pieces. After sawing the velvet, hold the thick paper piece and press the powder onto the saw wound, then twist and press the drug evenly onto the saw wound with the hand. For individual deer with severe bleeding, after evenly twisting and pressing the hemostatic drug onto the saw wound, cover the saw wound with a small plastic sheet and tie it to the antler base with straw rope to stop bleeding. Remove the plastic sheet and thin straw rope within 24 hours to prevent prolonged time causing necrosis of the antler base and loss of antler growth capacity. After velvet sawing is completed, for deer restrained by the mechanical restraint method, release the restraint device and let the deer out. For deer anesthetized with succinylcholine, let them recover naturally. For deer anesthetized with Miannaining, Huisuling can be used to revive them, or they can be allowed to recover naturally.