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Velvet Antler Removal
The first question to ask yourself is do you want to harvest velvet antler form your reindeer? If the answer is yes, then you should make sure you have the proper handling and restraining equipment. Without adequate facilities, you risk injury not only to the reindeer but also to yourself. Is the payment for the antler worth the risk of injury?
Once you have decided to go ahead with velveting, you should find your buyer. Every buyer will have a different time in which they prefer to cut velvet antler, therefore knowing which buyer you are using will help determine when you are cutting. IF you do not have a buyer identified, you may use the following as guideline.
Remember the actual number of days the antler needs to grow seems to vary depending on when growth is initiated. Velvet antlers all have a characteristic look when they are ready to harvest.
The main beam will reach a point where it has just started to curve forward and the bulb is out on the end. The bulb will grow to the point of almost splitting into 2 branches but will instead sit dormant for about a week. You should identify when the dormant stage occurs because antler will be calcifying at the base, thus losing a lot of value. You can see that prime antler will be very oily and glossy in appearance.
The following table may provide a rough guideline to properly time removal of velvet antler:
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Age
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Number of Days from First Budding of Antler
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Yearlings
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45 – 50
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2 years
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50 – 55
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3 years
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55-60
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4 years
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60 – 65
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5 years and older
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65-75
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Once you have determined the antler is ready for harvesting, be sure to take care when running them through the facility as not to damage the velvet; it is very sensitive at this point. It may be best to separate males and females prior to calving. This will alleviate the stress put on the young calves when you want to remove antler. When the females’ velvet antlers are ready to harvest, the calves are usually big enough to be safe from injury. You may choose to do only your bulls and dry females.
Some buyers may only want the main shaft and browtimes as shovels don’t have much value. These may be left on and cut in hard antler which is then used from crafts of many types.
Nerve Supply
Antlers are supplied by 2 relatively large nerves. The nervous system can be compared to the branches of a tree. The major nerve supply in all cervids comes from the infratrochlear nerve and the zygomaticotermporal nerve.
Antler Anesthesia
Lidocaine or other anesthetic drugs have been historically used to block the transmission of impulses along the nerves. Correct infiltration of local anesthetic drugs around the nerves which supply the pedicle and antler will provide full analgesia and completely block pain sensation in the antler.
Types of Lidocaine
Lidocaine can be purchased from veterinarians or pharmacists in most parts of Canada. Lidocaine is usually sold combined with epinephrine. Lidocaine without epinephrine is usually sold as Lidocaine Neat and is recommended for use in velvet antler removal. Lidocaine buffered with 10% sodium bicarbonate reduces pain of injection and provides excellent anesthesia. It is often used for injection in children. Epinephrine causes the blood vessels in the area to contract to reduce bleeding but prolongs the anesthesia. It is a very useful combination for many surgical procedures and the repair of wounds. However, epinephrine may slow or decay the onset of anesthesia, especially when used for antler removal. Lidocaine usually carries a withdrawal time for milk or meat.
Ring Block
The accepted technique for creating local anesthesia of the antler is called ring block. A ring of anesthetic solution is placed around the base of the pedicle. This effectively blocks all nerve transmission from the antler to the pain centers of the brain.
The injections are a series of overlapping lines of local anesthesia under the skin at the base circling the entire pedicle. To make a line of anesthetic, fully insert 1 and a ˝ inch long 18 gauge needle on a syringe of lidocaine under the skin of the skull where in joins the pedicle. Inject the anesthetic solution as you slowly pull the needle out. There should be a 1 ˝ inch line of anesthetic deposited under the skin. Repeat this procedure, overlapping the lines slightly, until the pedicle has been completely encircled. The volume of lidocaine needed is about 1.24 ml per cm of pedicle.
Performing the ring block can be difficult if the skin is closely attached to the skull, especially in reindeer. Try to inject in the area of the head a little farther from the pedicle where the skin is looser.
Analgesia
Analgesia, or the absence of pain sensation, should occur rapidly if the local anesthetic has been correctly placed. Incorrect placement or insufficient amounts of drug results in delayed onset or total lack of analgesia. Allow at least 3 minutes after injection for the drug to take effect before attempting to cut the antler.
Testing your results
Prior to cutting the velvet antler, the degree of analgesia should be assessed. There are no direct tests to evaluate antler anesthesia, but these indicators have been used:
- Squeezing or flicking the velvet antler
- Fine needle prick around the base of the antler, and
- Small initial saw cut
Apply these tests to the lateral part or outer side of the antler base where nerve supply is greatest. If they react by flinching or movement of the head, anesthesia is not complete.
Other Anesthesia
Electro-immobilization
The following explanation of electro-immobilization (EI) is quoted from Section 2.3 of the Canadian Recommended Code of Practice for the Care and Handling of Farmed Deer (Cervidae).
EI is NOT a form of anesthetic. Electro-encephalograms and other evidence show that animals undergoing EI are fully conscious and sensitive to pain.
There is no question that EI produces immobilization. It renders and animal immobile almost instantly. However, there is no scientific proof that EI offers any pain relief. Using EI to immobilize and anesthetize animals for velvet antler removal is considered to be inhumane by many.
Note: The Canadian Veterinary Medical Association has adopted a position that EI is unacceptable and objectionable from an animal welfare prospective.
Electro-anesthesia
Electro-anesthesia (EA) is also called transcutaneous electrical nerve stimulation (TENS). TENS is widely used in human medicine, including dentistry, to block pain. EA is achieved by passing a low voltage electrical currant across nerves causing a reverse flow or blockage of impulses. IN sensory nerves, this has the effect of locking or short circuiting the pass ways for pain. The result is analgesia or lack of pain sensation in the area served by those nerves. Supporters of EA believe that when this modified electrical current is applied to antler nerves, it causes enough analgesia in the antler to allow amputation. Research projects conducted to date appear to confirm this belief.
EA is performed by positioned electrode clips at the base of the antlers, across the skull of the animal. Typically, one electrode clip is attached to the skin in front and the other behind the pedicle. Alternatively, the electrodes are placed one on each ear. The electrodes are the unattached to a machine which converts electrical current into the correct form for delivery to the animal. It is critical that good contract be established between electrodes and the skin of the animal. Hair and oil on skin serve as insulators and prevent transmission of electrical current. The use of electrocardiogram (EKG) gels, which contain electrolytes, is recommended to ensure that an electrical field can be established to achieve anesthesia.
Due to the unique insulting properties of reindeer hair, EA is not suitable for use with reindeer unless the hair is shaved at the site of application of the chips of ensure good contact. IN addition, the skin on the skull is attached very firmly, making it hard to secure the clips. For these reasons, EA cannot be commended for antler removal on reindeer.
Compression Analgesia
Compression of tissues and nerves has been used to supplement anesthesia and control bleeding for many years through the use of tourniquets of various types. The use of compression to provide anesthesia for removal of velvet antlers was first used by New Zealand researchers during the 1997/1998 velveting season in New Zealand (Matthews et al. 1999). They reported that excellent anesthesia was achieved. However, there was a trend to reduced antler production in the following season.
A modified compression technique using rubbing tubing as a tourniquet around the pedicles was evaluated by researched from Agriculture and Agri-food Canada in elk. Compression was shown to provide some analgesia during the removal process. This method shows some encouraging signs for pain and stress reduction and can be applied following injection of lidocaine.
Tourniquet Application
Tourniquets are devices placed tightly around the body part to control bleeding. They are positioned between the heart and the location of bleeding. Before antler amputation, a tourniquet should be placed around each antler pedicle between the skull and the base of the antler, or coronet. The tourniquet prevents the heart from pumping blood from the severed blood vessels.
Effective tourniquets are flexible and elastic so that they conform to the shape of the pedicle, and remain tight when they are stretched into position. Rubber surgical tubing or strips of inner tube make good tourniquets. Baling twine, rope, wire etc. should never be used because they do not stretch and will cause serious damaged when tightened to stop the bleeding. Rubber surgical tubing should be applied to one or both pedicles by wrapping the tubing around each pedicle 2 to 3 times while stretching the tubing enough that it appears white. If there is bleeding following antler removal, the tourniquet has not been applied tight enough to compress the blood vessels.
Discard or clean and disinfect all tourniquets between uses. Blood and hair are easily removed from surgical tubing or rubber strips in a pail of water and disinfectant. Change the water and disinfectant in the pail frequently.
Antler Removal
After anesthesia and control of bleeding are assured, cut the soft antler 1” above the coronet using a clean, disinfected and sharp cutting tool of your choice.
The most common instrument used for cutting velvet is a course tooth hand saw used in wood working (back saw). Meat saws, hunting saws and other coarse tooted saws may also been used. The type of saw is not as important as its sharpness. A fine tooth or dull saw performs poorly. Besides more effort requires by the operator, it can damage the antler by tearing the skin on completion of the cut. Choose a coarse saw, one that has relatively fewer teeth per inch. For this reason, the obstetrical wire or bone cutting wire frequently used in dehorning cattle is not effective for removing velvet antlers.
Pay careful attention to cleanliness and disinfecting of the saw. IT should be rinsed and disinfected between each animal with a non-toxic, food grade disinfectant or alcohol. Keep your saws and tourniquets in a large pail of disinfectant when not in use on an animal. Iodine disinfectant, such as Sani-Kleen 77 by Dustborne should be used whenever possible.
Identify the line on the antler above the coronet where the saw cut will be made. This line of removal should be able 1” above the antler-pedicle junction (coronet). In some animals, the shovels are very close to the head. In this case, make 2 cuts. Remove the shovels with the first cut and make the second cut on the main beam. Cut through the antler along your pre-determined line of removal with relatively long, smooth strokes. Some operators begin the cut between the antlers, moving to the outside of the antler. Others prefer to cut from the outside to the center. Use the methods that allow you to remove them cleanly and quickly. Most important, cut parallel to the coronet and do not allow the angle of your cut to carry your saw into the pedicle. Support the antler during the cutting so that it does not fall and strip the covering skin off the antler.
Animals with inadequate local anesthesia will show pain by attempts at head withdrawal and general struggling. Sensation to the antlers persists if:
- the local anesthetic was not injected in the right location,
- too little anesthetic was injected to produce local anesthesia
- the operator has not waited long enough for the anesthetic agent to take effect,
- compression has not been tied tightly enough
It the animal responds poorly to cutting, adjust the local anesthesia. Try these things:
- wait awhile longer for the initial block to take effect
- add more local anesthetic to the blocking sites
- increase the tension of the compression device
Tourniquet Removal and Hemostasis
After removal of antler, apply hemostatic powder to the cut surfaces and allow a brief period for the powder to work before removing the tourniquet. Heat cautery (cauterizing) is not necessary or advisable. Observe the antler stumps for excessive bleeding before releasing the animal.
Blood flow from the cut surfaces varies from minor oozing to some spurting of small arteries. Blood pumping from several large arteries is considered significant bleeding. These animals need observation. Intervention and treatment may be necessary if there is no reduction of bleeding within 5 to 10 minutes.
Another method to control bleeding is to apply a wide, brown elastic band over the cut end of the remaining antler. This helps prevent unnecessary bleeding and with deteriorate in sun and fall off within a few days. Once the elastics fall off, regrowth of the antler will begin.
Note: Tourniquets left on an animal will result in permanent damage to the pedicle and abnormal or poor antler in the following years. Do not forget to remove the tourniquet after removing the antler.
It is important to prevent flies from laying eggs in the edges of the exposed velvet. Maggots in the antlers can cause major problems. If you end up with a maggot problem, be sure to treat it quickly and thoroughly.
Wound dressing of fly repellant such as Boroform or KRS to prevent insect activity on the pedicles can be applied if needed. Control of bleeding is also important so that flies and other insects are not attracted to the animal.
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