Advances in Sheep and Goat Medicine

0749-0720/90 $0.00 + .20

Routine Sheep and Goat Procedures

Christine S. F. Williams, BVSc, MRCVS*

MASS HANDLING Although you can usually win in a battle of physical strength with an individual sheep, in the long run you lose, because there are more sheep where that one came from, and you cannot sustain the effort. Large-scale producers know this and invest in cleverly designed systems based upon animal behavior, to ensure that the animals move themselves, with minimal human involvement. Smaller producers, especially hobbyists, rarely have handling systems, and so there is the real risk that health programs will be delayed or not instituted at all, if the effort required is too great. People with limited physical capabilities can easily be hurt, and muscle sprains and bruises are common to everyone after a day of wrestling sheep. Handling systems that are properly designed12,13 allow sheep to How through smoothly, with no balking or mad dashing. If the latter happens, there are fundamental design Haws. When you have to work with sheep and there is no handling system, it is necessary to pack them into a small space, just big enough for you and a group of sheep. There should be four good solid sides to the enclosure, because the pressure exerted by massed sheep is substantial. Visual barriers will collapse and hog panels will bend, perhaps resulting in broken legs in this situation. If you can make a long working pen, 3 to 4 feet wide, you can fill it with sheep and then work your way along it, keeping the treated sheep behind you, separate from the untreated. If you have spindly legs, a long coat will make you into a more effective visual barrier. Sheep raceways are only 15 to 18 inches wide, designed for single file movement, with no turning around, and there is not sufficient room to stand in these raceways. You can work outside them by leaning over and injecting, ear tagging, and perhaps dosing orally. It is important that these raceways remain full of sheep. If there is a gap, a determined sheep can get a running start and launch itself up and over the backs of sheep ahead of it. When this happens there is· a real risk of physical injury if you are bending your head over the *Director, University Laboratory Animal Resources, Michigan State University, East Lansing, Michigan Veterinary Clinics of North America: Food Animal Practice-Vol. 6, No.3, November 1990

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raceway. Although there are always individual differences, the behavior of western range ewes makes them easier to handle in a chute. Farm flock ewes are harder to work with; they swing their heads around much more frequently. Weigh scales, tipping cradles, and treatment crates can all be incorporated into the traffic flow. Some cradles tip the sheep on their side; others tip them over on their backs, with the feet at a comfortable height for stand-up, straightbacked foot trimming. However, some of these devices, although very effective, are complex, and they should be used only by skilled team members. An untrained person could break an arm or get a sheep leg trapped and broken. INDIVIDUAL RESTRAINT Although most rams are fairly friendly, none should be trusted. Some bloodlines in certain breeds are characterized by extremely aggressive ram behavior, which gets worse in the breeding session. Even a friendly ram may charge if you catch and restrain a ewe, especially if she is in heat. For this reason all farm flock rams should have collars and be tied up before you work with ewes. An added advantage of the collar is that it gives you something to grasp if the ram becomes physically aggressive. If you catch the collar, he will not be able to back away and charge again. A bell helps to warn people about rams that charge from behind. Rams will swing their heads around when restrained, and if they can get their head down and start moving, they are very difficult to stop. With one hand on the collar and the other under his chin, pushing his nose up, a small person can stop most rams. You may be more successful pushing a ram backward than trying to pull a stubborn one. If you pull hard on the top of the collar, you cut off the blood flow to the head and the ram will drop to his knees and have a minor convulsion, lasting about 15 seconds; instead, pull on the bottom of the collar. The current interest in giant sheep has led to rams so big that they are difficult to shear. This problem can be overcome by giving the giant ram 15 mg xylazill:~_ IV ~nd then positioning him next to the shearing board, so that when he drops he is in the right place. Trim the feet (and other desired areas) while he is sedated. Ewes and big lambs can be restrained by holding the wool and skin under the chin and by holding the tail head with the other hand. Raising the tail head makes the sheep move, usually forward. If she goes backward, just swivel her 180 degrees for desired positioning. Catching sheep by the wool is not acceptable; it is painful and also causes bruising, with resulting blemishes, on the carcasses of slaughter lambs. There are various ways of tipping up a sheep, to get it to sit on its rump. Picking up the sheep is ridiculous, but you still see it done. Pulling a leg out from under the sheep is another way. The easiest way is to stand on the right side of the sheep, with the right hand under the jaw, right thumb over the muzzle, left hand placed flat on the rump. Suddenly swing the sheep's nose back onto its left chest wall and push down hard with the left hand, and the sheep will become disoriented and sink down to the left and behind you. Change the position of your feet and stand with the sheep's back and head supported against your legs (Fig. 1). If you push down on the front end of the sternum, this will make the spine curve and the sheep may relax more. There are breed and age differences in how easily sheep will relax or '"give up." Compact muscular sheep such as old-fashioned Dorsets, do not relax; nor do 100-lb ewe lambs on full feed, which kick considerably. Under no circumstances should a volunteer try to help by holding the hind legs; it only gives the sheep something to kick against. Lambs on lush alfalfa or clover should not be

ROUTINE SHEEP AND GOAT PROCEDURES

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There are breed and individual differences in dairy goat behavior. The La Mancha breed, with little or no ears, is generally stoic and easy to handle, whereas certain individuals of the Nubian breed are extremely difficult. Goat bucks are a different problem; they reek, particularly so in the breeding season (fall and winter). Some of this is due to the habit of urinating over the front legs, face, and beard, and some of it comes from the scent glands. However you handle the buck, you will acquire the same reek. Goat bucks fight by rearing up and then crashing down and butting heads. An aggressive buck may rear up on you, so caution is indicated. When you are restraining a goat buck, your intent is to not let him get his head up so he cannot rear up. Hanging onto the beard is extremely effective, if you can bring yourself to do ill Even when bucks are clipped for show, the beard is usually left on, so do not shave it off unless absolutely necessary. Angoras have horns, and these are useful to hold onto, especially when the animals have been sheared and there is no chin hair and very little chin skin to hang onto. Occasionally, a kid horn will come off in your hand; usually, this is in a flock with poor nutrition, or the kid is not growing well, but that is no consolation. If you pick up a half grown kid and hold it against your body, sooner or later it will stiffen, then struggle and poke its horns in your face. Lambs with scurs seem to be able to do the same. Dairy goats usually do not have horns, but if they do, hold onto them, as well as the collar, and keep the goat sandwiched between you and a wall. They do not like their horns held, but it is dangerous to not hold them. The most useful restraining device for helping one person handle sheep or goats is the Gambrel restrainer· invented in New Zealand. You put the front feet up close to the ears and the animal lies quietly (Fig. 2). When you are working alone, fixing dystocias, it is much easier with a Gambrel than with a collar, halters, and so on. *Available from Premier, Box 89, Washington, IA 52353

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To restrain a ewe and stop her straining on a vaginal prolapse, the least expensive yet most effective method I have found is a baler twine harness. There are various ways of designing it, but the goal is to apply pressure against the vulva. With the design shown (Fig. 3), the pressure is applied via a rectangle of knotted twine. Wool should be wrapped around the twine at points where it might chafe the skin. The twine should be so tight that the ewe is almost ready to drop to her knees. This, after all, is akin to the classical method of casting livestock with ropes. After awhile she will get more comfortable and walk around normally. If the harness loosens, attach some more strategically placed twine to take up the slack. SAMPLING The jugular vein is the easiest place to obtain a blood sample. Sheep should be backed into a corner and held with the neck in a natural position, not twisted to one side, and the head pointing straight ahead, perhaps slightly stretched forward. The handler is equally as important as the sampler. Shearing is not necessary if the wool is long and parts easily. However, it may be necessary if you have a fat-necked muscular sheep with half an inch of springy wool on it, which makes it difficult to palpate the jugular vein. Single-person bleeding techniques exist lO (Fig. 4). If you are right-handed, set the sheep on its right rump, resting against your right leg. With your left hand, push the head down onto the sheep's left side. This will raise the right jugular vein without manual occlusion. Shear the neck if you cannot see the vein. Also, you can stand astride a sheep or hornless goat, and using your left elbow to push the head to the left,

Figure 3. Baler-twine prolapse harness.

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Figure 4. One-person bleeding technique. A, Person sitting. B, Person standing.

you can hold off the right jugular vein with your left hand and bleed the animal with the right hand. However, you cannot do this if you have short legs or the sheep are high strung and tend to jump forward. Small lambs and kids that wriggle can be held between your knees with the animal's feet off the ground (M. Smith: Personal communication). Because most sheep and goats will urinate when they stand up, you can collect urine by quietly entering the barn while the animals are still lying down and using a paper cup taped to a fishing rod. Do not use a metal cup because animals will stop urinating when they hear the sound it makes. The classical method of cutting off their air by holding the nose may be effective, but it will not impress some companion animal owners. In this case, a bitch catheter inserted blindly works very well on ewes and does. Avoid the clitoral fossa, which is about 1 inch inside, and aim for the spot where the vagina proceeds over the rear brim of the pelvis. If you cannot do it blindly, guide the catheter in, under your gloved index finger. Bucks and wethers cannot be catheterized easily because there are three obstacles: the urethral process, the sigmoid 8exure, and the urethral recess at the rear brim of the pelvis. IDENTIFICATION How you identify sheep and goats will depend on registry requirements for pedigree animals and the owner's preference for commercial animals. Registered Angora goats have to be tattooed as well as ear tagged or notched. Dairy goats are never ear tagged or notched for registration or show purposes. Commercial dairy goats have neck tag numbers if necessary. Sheep breed societies have metal tags that they distribute after the application for registration has been made.

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Tattooing If tattooing is done poorly, the numbers will become illegible later. To do it properly, clean the ear with alcohol. Prepare the tattoo code, inspect it by punching a piece of paper, and then scrub tattoo paste onto the needle points. After you have clamped the ear, remove the clamp, put paste on a toothbrush, and scrub into the puncture holes. Use black paste on light skin and dark green on dark skin. To tattoo La Manchas (no ears), put the mark on the tail web. Roll-on inks are not always successful in the hands of neophytes. Ear Tags Ear tags come in many shapes and sizes-metal and plastic, large and small-but there is still no tag that remains in for the lifetime of 100% of sheep and is easy to read from a distance. The tiniest, least expensive tags are brass chicken wing tags. * these are useful for identifying newborn Finn lambs, whose ears collapse under the weight of other tags. They are also useful as a fall-back tag, in addition to the main tag. If the large tag rips out, the small one should still be there. When these wing tags are put in lambs' ears, they should be placed with half the tag extending beyond the edge of the ear. This will allow for growth. Other varieties of tags are either self-piercing, which is fast, or require punching a hole and then putting the ear tag through it, which is much slower. Granulations may occur, but they seem to occur less often with plastic tags than with metal tags. Where you place the tag depends on how the owner wants to read the numbers. People who sort sheep by number coming down a race at speed need the numbers on the side of the sheep closest to the person standing by the sort gate. The number should be large, facing forward, and hanging from the lower border of the ear. If you want to identify sheep from a distance, from any direction, use large tags with numbers on both sides. People who sort sheep by looking down on them (useful when they are in the scale or stopped in the race) put button tags Hat on the top outside of the ear, and people who look for individual sheep while they are eating at the feeder need the hanging tags with numbers facing backward. The system I currently use involves a chicken wing tag in the left ears of newborn potential replacements, and a Rototag* in the right ear of all ewe lambs and left ear of wether lambs. Ewe lamb replacements get a second tag, which is large and double-sided, in the left ear as soon as they are confirmed pregnant. Ear tags and applicators should be kept clean and placed in alcohol or other disinfectant immediately prior to use. New ear punches are sharp and cause more bleeding than do blunt old ones. Also, ears bleed much more on warm days, so if possible, ear punching should be done in the cold. The self-piercing tags cause much less bleeding. Black numbers on light bright tags are easier to read than are white numbers on dark tags, because the white numbers get covered with sheep grease. FOOT TRIMMING Foot trimming is a necessity brought on by intensification. Range operators with thousands of animals spread far and wide rely on the sheep and goats to wear their own feet down by trailing across rocky or sandy ground. Farm Hock

·Available from Premier, Box 89, Washington, IA 52353

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operators who keep sheep and goats on heavy productive soils, with bedding in the barn, will have to do some of the work themselves. Meat breed sheep, with low wool growth, tend to have slow horn growth, whereas the wool breeds tend to have faster growth and need trimming more frequently. Failure to trim feet does not cause foot rot, but it may lead to foot abscess or lameness if the overgrowth breaks off or cracks and dirt enters the hoof. It is unwise to attempt to trim the feet of sheep housed on a dry straw/manure pack in the barn. The feet will be extremely hard. Likewise, in very dry summers, the same situation may occur. Wait until ewes have been out in the rain for a few days and then trim the feet, after the wool is dry. Animals kept for show purposes will need their feet trimmed perhaps every 2 months, to ensure that the pasterns do not change their slope. Never trim a foot the day before a show. If the animal goes lame or stands awkwardly, it will place badly. Goats in particular may stand with their rear pasterns sagging and their toes spread for a day or so after trimming. The traditional, very difficult method is to set the sheep or Angora goat on its rump and then lean over the animal and trim the back feet first. In this manner, you avoid the possibility of injury from the animal's sharp trimmed front foot while you reach for the back feet. A less difficult method is to use a sheep chair, but this involves catching the animal and getting it into the chair; you still have to bend over, but not so far. The easiest method uses a cradle at the end of a raceway, where the sheep is tipped on its back and the feet are at a convenient height to trim. Dairy goats are usually trimmed while on a stanchion milk stand about 12 inches off the ground. Simply lift a front foot off the ground and bend the leg at the carpus. The hind leg is more difficult to manipulate, and the goat may kick. Stand at the side of the goat facing the rear. Place your left knee under the goat between the udder and the left hind leg, pick up the foot, and keep the leg Hexed. This reduces the risk of leg damage. The ultimate in equipment is the compressed air power-assisted shears. However, these are dangerous in the hands of an inexperienced person, and it is possible to amputate a foot or finger with them. The two basic designs for hand shears are the Burdizzo foot rot shears with straight handles,· and the Felco design with contoured handles for easier use and more leverage. t People with small hands cannot open the Burdizzo handles to their full extent, so the blades are never open to the full range. This necessitates making two small cuts instead of one large one. Drilling holes in the handles and putting a leather strap between them stops the handles from opening too far and makes it easier to close them. The Felco shears with the rotating handle are helpful for people with small hands or who get blisters easily. Although you can use garden shears and other devices on a few animals, the true test is whether you can use them comfortably on many animals. I prefer the Burdizzo for exploration and drainage of foot abscess, and the Felco for bulk hoof trimming. Both styles work better when they are sharp, and sometimes one works better than the other depending on the consistency of the foot. The six-cut system, defined by Vicary,14,15 is a sequence of cuts to achieve optimal results with minimal effort. The goal is to restore the foot to the shape it was when the sheep was born. In this way, the natural wearing of the hoof is maximized, thus extending the time between trims. The heel should not be

·Available from Nasco, 901 Janesville Avenue, Fort Atkinson, WI 53538 tAvailable from Premier, Box 89, Washington, IA 52353

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trimmed except to remove Haps of overgro~th. Dig out the dirt, which would blunt the shears and is very difficult to cut when dry, and so expose the sole. Make cut 1 across the front (Fig. 5A). With experience you will get it exactly at the right depth, so you can just see a faint pink color in the sole. Cut 2 makes the outer wall Hush with the sole. Cuts 3 and 4 should be at an angle, so more inside wall is removed. Cut 5 is the same as cut 1, except in the opposite direction, and cut 6 is same as 2. My version of the six-cut system (Fig. 5B) involves no wrist direction changes, so it may be slightly easier and/or faster. Goats with very long toes will rock back on their heels. Incorrect trimming will make this worse and leave the toe pointed up in the air, with the goat still walking on its heels. Known as the Dutch clog foot, such feet cannot be corrected in one session but can be corrected by sequential alteration in the angle of the bearing surface of the foot (Fig. 6). Occasionally, goats' feet grow in a peculiar fashion, with little differentiation between the wall and the sole. This may be a sequel to laminitis. The horn is very hard and cannot be cut with regular shears. Farriers' hoof nippers or a hack saw blade is needed to cut them back if the goats are walking on dry bedding.

DOCKING There are no regulations in the United States regarding docking. This is in contrast to the United Kingdom, where there are regulations determining the minimum length of the tail. Breed standards or show ring fashions in the United States encourage ultra-short docking. Because it is a widely held notion that short docking predisposes to prolapses of the rectum and vagina, breed societies should be urged to change their standards to prevent unnecessary suffering of the animal and financial losses to the owner. Where hothouse lambs are sold very early, with no access to lush pasture, there is no reason to dock them, nor to castrate. Half Finn ewes do very well on pasture with their natural tails; quarter Finns may not. There are three main methods of docking. One is the rubber ring, another is a combination of clamp and cut, and the third is cautery. To get the tail long enough to cover the vulva, it should be cut around the end of the tail folds, which are ventral and bare-skinned. Remember that as lambs fatten up, the tail gets shorter. 1

1 3

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B Figure 5. A, Vicary's six-cut system of hoof trimming. B, Modified six-cut system.

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Figure 6. Correction of goat's hoof with toe pointing upward.

Although it is often stated that lambs should be docked as early as possible to minimize pain and distress, there is no evidence that there is any difference in the lambs' behavioral reaction during days 1 to 7. 8 Although many people claim to be able to dock and castrate on day of birth, there are some sound reasons why this should not be done. If docking and castration in any way deters the lamb from sucking, colostrum intake will be diminished, putting the lamb at greater risk of hypothermia and/or infection. Methods (1) Rubber rings. These are fairly simple to apply in a one-person operation. Lambs may throw themselves around for about half an hour, then return to normal behavior. On farms where there is a risk of tetanus, lambs can be given 150 IU antitoxin, if the ewes were not vaccinated previously. Tetanus appears to be more common following the use of rings than with any other method. (2) Clamp and cut. This can be achieved with an emasculator or with a Burdizzo clamp and a knife. Some lambs will bleed, especially if it is a warm day or if they are large, fat singles. (3) Hot docker. The low-tech version is a chisel heated in a campfire. The high-tech versions are electric and propane-heated docking pliers. Lambs show very little reaction after this method. Occasionally, a ewe may try to reject a lamb because of the smell of burned wool. This method should not be used by the ultra-short dockers, because burns to the anus and vulva are likely. It is important to put lambs onto clean bedding after docking and castration during which open wounds are produced. If a ewe chews on a newborn lamb's tail, it should be immediately docked properly, because a mangled tail often becomes infected and may lead to an ascending infection in the spinal cord.

CASTRATION Dairy and pygmy goats should be castrated if they are intended to be companion animals. This will reduce the smell and the aggressive behavior. Angora goats are castrated so that they can be run in wether Hocks for mohair production. Sheep are castrated so that Hocks and feedlots can be managed without unwanted pregnancies. Although there is evidence to show that young entire ram lambs produce a more desirable, leaner carcass, sheep raisers will

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still castrate lambs if the packers, as they are currently doing, substantially discount buck lambs. When castrating sheep and goats for 4-H wether projects, check the show rule book for definition of a wether. If it defines a wether as an animal with no testicles, then a late Burdizzo clamped animal, with small, atrophied testicles may cause a problem. There are basically three methods in use: the rubber ring, the Burdizzo clamp, and the knife. Rubber Ring Although this method is considered less stressful to the owner because there is no cutting or blood loss, it is nonetheless stressful to the lamb. Most lambs will act as if they are hurting for up to 1 hour after they are castrated by this method. They will throw themselves on the ground, get up, fall over, and so on. Although it is generally said that one should perform this technique as early as possible to reduce stress, there is no evidence that the behavior of lambs is any different between 1 and 7 days of age. 8 As with docking, this operation on the day of birth is contraindicated if it reduces colostral intake. There are several problems that might arise with this technique. Inexperienced people may apply the band after the testicles have retracted, so all that happens is that the empty scrotum falls off. These accidental, short-scrotum lambs are a nuisance in the feedlot, because they behave like rams. Some people intentionally "short-scrotum" lambs, perhaps in an attempt to avoid the packer discount. If the band is applied too high, it might trap the urethra. The nipples should always be above the ring. If the lamb seems uncomfortable for more than the usual hour, check the ring and remove it if in doubt. Tentanus is a potential sequel on certain farms, and antitoxin should be given at 150 IU per lamb if this risk is considered high enough. There are no laws in the United States regarding the use of rubber bands, but in the United Kingdom they must not be applied to lambs more than 7 days old, and the operator must be 17 years of age or older. The technique of applying the band to lambs that are 60 to 100 pounds and then cutting off the scrotum the next day may yield cosmetic results, but serious questions have to be raised concerning the humaneness of such a technique. Burdizzo Clamp The clamp should be applied to each side of the scrotum, making certain that the cord has not "popped out" of the clamp. If this happens you will get a one-sided buck. The clamp should not be applied once across the whole scrotum; there should be a central portion of undamaged skin with clamp marks on each edge. Dairy goats, meat goats, and sheep should be castrated at a young age, whereas Angoras, especially in the southwestern United States, are traditionally castrated at 6 to 12 months of age. This is done so that the animals develop bigger horns, which enable them to fight off predators better. Also, a more developed penis may reduce the problem of urinary calculi, on the assumption that calculi could pass easier down the urethra of a later-castrated animal than an early castrated animal. Techniques vary according to the preference of the operator. Some people clamp twice on each side, some attempt to pull on the testicle to ensure that the cord has separated, and others leave the clamp on for a set time. However, Texas Angora raisers, who may castrate several hundred yearlings at a time, get satisfactory results with a single clamp application on each side, with no waiting.

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Problems of Burdizzo clamping are that older animals may get scrotal swelling sufficient to make them uncomfortable and walk stiffiy for 4 to 5 days. This can be avoided by castrating them as early as possible. If the clamp is applied too close to the body, it is possible to include the urethra, with disastrous consequences. Clamps that do not fit tightly, perhaps those that have been used on large lamb tails, may not give uniform results. Knife Castrating with a knife guarantees that there will be no possibility of a functional testicle remaining. Cut off the bottom one third of the scrotum, then pull out each testicle, which is slippery and tries to retract. In order to hold onto it with finger and thumb, you have to press your thumbnail into the side of your index finger, and your finger will get quite sore after castrating a lot of lambs, which many will still prefer to using their teeth. There are castrating knives available that have clamps on the end of the handle, which substitute very well for teeth. Problems of castration with the knife are that lambs will be stiff and spend a lot of time sitting down quietly for a day or so. Also, the wound provides entry for infection, so lambs should be placed on clean, new bedding after castration. If tetanus is a known risk on certain farms, antitoxin may be given. Blood loss is another possibility. Some people try to reduce this by scraping the blood vessels with a blunt knife until they break; others believe equivalent results are obtained by steadily pulling on the cord until it snaps and the arteries retract and self-seal. If blood does start to drip steadily, tie a string around the neck of the scrotum and hope that an internal blood clot will form. Mark the lamb so you can find it later that day to remove the string. After the lambs have been castrated, let them rest quietly for the remainder of the day. DOSING Although it is easy to dose newborn lambs or kids with pills, it is much more difficult to give boluses to older animals, even with a balling gun. They are adept at recognizing them and spitting them out minutes later. This uncertainty about whether the dose was retained, together with other considerations such as cost per bolus and difficulty with administration, make it more likely that people will choose to administer medication in liquid form or by injection. Small amounts can be given orally with an ear syringe or a disposable syringe. Oven basters or 60-cc catheter tip syringes are useful, provided the ends are kept smooth (the molars can cause a lot of damage to equipment). Automatic dosing guns are convenient and time saving, especially if attached to reservoir packs. However, they should always be checked to be certain that they are actually delivering the desired amount. Because it is a preset dose, based on an estimated weight, some animals will be overdosed and some underdosed unless you keep altering it, which negates the reason you used the gun in the first place. When dosing sheep orally, the head should be kept in a reasonably normal position, to enable the sheep to swallow rather than inhale. Dosing guns and balling guns used improperly can cause pharyngeal and esophageal trauma. Large volumes can be given by stomach tube (foal size for adult sheep and goats). Lambs are often stomach tubed with colostrum instead of bottle feeding. 3 Tubing is indicated when there is poor sucking re8ex, because bottle feeding a reluctant swallower usually leads to inhalation pneumonia. Tubing is also a temporary measure to feed potential foster lambs; this stops them from

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becoming fixated on humans and milk bottles. Lambs that need oral fluids should be tubed with calf electrolyte mixtures with added glucose for energy, to a final concentration of 10%, i.e., 10 g glucose in 100 mL.4 The technique for stomach tubing lambs is as follows: Wrap the lamb in a towel and sit it on your lap, facing away from you. Lubricate the tube. Hold the jaw with your left thumb and forefinger, with the fourth finger resting across the neck, as far down as you can reach. Thread the tube in with your right hand, and slide it down the back of the mouth. If it is going down the esophagus, you will feel the tip going past your fourth finger. After the 15-inch tube has gone down so far that only 1 inch protrudes from the mouth, attach a catheter tip syringe and inject slowly. Distention of the stomach may cause the lamb to struggle, and it usually urinates anyway (that is what the towel is for). Concerns about the tube being in the trachea are alleviated if you felt the tip going by and the tube went in all the way. A standard lamb stomach tube is too wide to coil up in the trachea, so if it went down 14 inches in a small lamb, it cannot be in the trachea. A piece of fishing line tied to the tube is a good precaution in case a large lamb swallows it. If you do, by accident, get the tube into the trachea and inject colostrum, the lamb will not cough; it will drown quietly. It will struggle a bit, then go limp, with gradually decreasing respiratory efforts. DEHORNING Because of the relationship between polled genes and intersex genes, it has so far been impossible to produce a strain of polled goats that does not have a problem with infertility. Because goats have such a strong hierarchic social structure, it is not advisable to keep both polled and horned goats together in close confinement. Besides injuries, there is the risk of some goats being unable to cope psychologically, and they will never thrive and produce to their full potential. Dehorning a mature doe will drastically alter her position in the hierarchy, and she should not be put back with her polled pen mates until her head is fully healed. It is not easy to put one goat back into an established small group, so it is better to introduce several. There is less chance of injury and psychological stress if all the goats are in a large pen with multiple feed and water points, rather than several small pens, even when the space per goat is the same. At 25 ft2 per goat in a large pen, there is not much fighting; at 20 there is some, and at 15 there is much. In a large pen, the attacked goats have enough room to run away. It is obvious, then, that it is better to have either all horned goats or all polled goats that have been disbudded at birth. In France, the majority of dairy goat herds in confinement are horned and there is strong selection against the polled gene. In the United States, dairy goat herds are usually polled, with a mixture of heterozygous naturally polled and disbudded goats. Angora and range meat goats in the southwestern United States are usually all horned, for defense against predators and for something to hold the goat with. Also, Angora goats can be sexed in a chute by their horns; does and early castrates have small horns, late castrates have intermediate-sized horns, and bucks have large horns. Disbudding Kids should be disbudded in the first two weeks of life. Buck kid horns grow faster than doe horns, and Swiss breeds have stronger horn growth than does the Nubian breed. You can delay disbudding Nubian kids, especially doe kids, up to 2 weeks or longer, but you cannot do this with Swiss-type buck kids.

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Some large single buck kids from longer than the average I50-day gestation will be born with horns. These kids should be disbudded at 2 to 3 days of age, provided the kid has good muscle tone and is drinking well. Disbudding a buck kid is the true test of proficiency and many fail it, judging by the number of scurs seen on adult stud bucks. Doing it well and early is the secret. If you try to dehorn a buck kid whose horn base is wider than a regular dehorning iron, you will get regrowth of the horn in a crown outside the burned area. If you try to dehorn a small kid with a wide calf dehorner, you may get regrowth of the horn from the center of the ring. Technique Goat keepers who have kept goats for many years usually dehorn kids themselves with restraint only and get very good results; they justify the lack of anesthesia as "brief grief." Neophyte goat owners take kids to an experienced disbudder or to a veterinarian. An inexperienced person could commit two errors. The first is to be too timid with time or temperature. This will lead to horn regrowth and scur formation. The second is to be too enthusiastic with time of application, and this will result in brain damage or death because of heating of the cranial bones. If one person is doing the job, a dehorning box offers the best and safest restraint (Fig. 7). Although local anesthetic is commonly advocated, the actual technique is not easy, and the baby goat will scream while being held securely in preparation for the injection. It takes a skilled person to hold a baby goat for a ring block, and because the skin is tightly attached to the bone, infiltration is difficult and you risk sticking the needle in your finger, the goat's eye, or your assistant. Nerve blocks can be used, but it is necessary to block four sites instead of two as in the calf. Although it is often suggested that goats are more sensitive than other ruminants to local anesthesia, it is more likely that adverse reactions are the result of overdosing. Baby goats are one tenth the size of calves. Problems of overdosing are convulsions or drowsiness. Keep drowsy goats in a warm place. If they will 7"

Cut out head hole after assembly

18"1

1%"

,

~

2"x8" stock

Figure 7. Dehorning box.

ROUTINE SHEEP AND GOAT PROCEDURES

751

not drink, administer subcutaneous dextrose saline. The difficulties with local anesthetic are the reasons why many kids are disbudded with physical restraint or general anesthetic. If kids can be brought to the animal hospital, the easiest and fastest technique is masking them down with halothane and oxygen. It also has the advantage of rapid recovery. However, remove the mask and gas How during cautery; otherwise, a Hash fire in the goat hair may result. Xylazine at 0.3 to 0.4 mg/kg2 is commonly used for injection anesthesia, and kids should be kept warm during the prolonged recovery period. The equipment most commonly used is an electric-heated metal rod with a hollowed-out end. None of the irons can be relied on to maintain a constant temperature, and it is extremely important to match temperature and time. Underburning will result in scurs and overburning will lead to brain damage or death. The kid horn bud is located over the sinus, but it is very close to the cranium, much closer than in calves. Goat horns grow faster and stronger than calf horns. Plug in the electric dehorning iron and let it heat up for a few minutes. Test the iron periodically for 2 seconds on a piece of pine board. When the iron leaves a circular black ring with a very slight depression in the wood, and smoke just begins to rise, at the end of 2 seconds, that is the "defined" temperature. Apply the dehorner firmly over the horn area and rock it around slowly for 3.5 to 4 seconds. Remove the iron and slide off the thin cap of horn. After a wait of a few seconds, repeat the process for another 3.5 to 4 seconds on the same site and then pull out the central core of tissue that is overlying the bone. Immediately spray with a pressurized aerosol of antibiotic powder, which will cause rapid cooling. Repeat the entire procedure on the other horn. Although it may be argued that removal of the core is not necessary for preventing regrowth of horn, the fact that it can be removed means that you have burned evenly all around. If it will not come out, you have not burned enough. Also, removing the core prevents later accumulation of pus under the necrotic center. Inject the kid with 150 IU tetanus antitoxin. Although the risk of tetanus after disbudding is not great, it is such a devastating experience for the owner to lose a kid this way that antitoxin as a routine is a good practice for companion goat herds. Correction of someone else's poor technique that resulted in scur formation or removal of kid horns that are too long to fit inside the hollowed-out dehorner requires general anesthesia. Shave the head and make a ring cut with the scalpel outside the horn base. All tissue inside the ring has to be removed or destroyed. Nip off short horns with bone forceps, and cut off longer ones with embryotomy wire. Then dissect all remaining skin and tissue back to the original scalpel cut. Then cauterize all bleeders with the dehorning iron. Do not apply the "defined temperature" iron for any longer than 5 seconds at a time. Caution: These irons get hotter if you wait too long after testing for the "defined" temperature. Always test the iron prior to starting a procedure. Dehorning Adult Goats Do not attempt dehorning on a mature buck, because the horns have such a broad base that, if you remove them, the holes may never close. Adult wethers have smaller horns, but even these are so broad based that a Barnes horn scoop will remove most of the bone covering the top of the head. In addition, there is the risk of fracturing the cranium, which is very close to the posterior horn base. Adult does can be dehorned under general anesthesia using xylazine, approximately 10 mg IV per large adult, plus the local anesthe-

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sia at four sites. One site is halfway between the inner canthus of the eye and the anterior edge of the horn. The other site is the same place as in calves and can be found halfway between the external canthus of the eye and the posterior edge of the horn (Fig. 8). Xylazine alone, even when goats appear to be deeply anesthetized, does not produce adequate analgesia for dehorning. Clip the hair of the top of the head, scrub the area, then position the doe in sternal recumbency, with an assistant kneeling astride the chest, holding the goat" s head in a normal position, as if the goat were awake. Position the embryotomy wire low down behind one horn and, while kneeling in front of the goat, start sawing off the horn. As you pull, the goat's nose will tend to tip down, and this will make your cut too high at the front, so the assistant must keep the head in the natural, muzzle-ahead position. The wire should be cutting below the skin-horn junction. As the wire approaches the front of the horn, slow down; otherwise, the saw will tear off some skin if the horn breaks off suddenly. With old wire, the horns cut slower and hotter and there may be no bleeding at all. With new wire there is a lot of bleeding and you may have to use hemostats or cautery. Do not use frayed wire; it always breaks in the middle of a horn. Mature goat horn is very hard and considerable effort is required. If there is any doubt that the wire cut was made below the skin/horn junction, go back and cut off a strip of skin all the way around and cauterize any bleeding points with a hot iron. When you have finished both horns, put a nonstick dres~ing over the two holes. Wrap a piece of gauze loosely around the head, just to keep the dressing in place. Then slide a piece of tubular stockinet over the head, cut ear holes and eye holes, and fasten it loosely around the muzzle and neck with elastic adhesive bandage. If you choose not to bandage, the wound will look dry at first, but then the sinus mucous membranes will swell and start to seep. There will be seepage for 1 week or longer. During this time the goat should be fed hay on the ground and be kept in a pen where the ceiling is clean. Because the holes are on the top of the head, foreign bodies dropping into the sinuses may cause chronic sinusitis. The goat will be "head-shy" for weeks and should be given plenty of space to escape from regular pen mates. Generally, if you make the

Injection site

Injection site

Figure 8. Nerve blocks for dehorning.

753

ROUTINE SHEEP AND GOAT PROCEDURES

owners assist during the procedure, they will never again forget to get the procedure done at an early age. DESCENTING "Descenting" is not a correct term because what you are really doing is destroying or removing the sebaceous glands that are located behind and slightly medial to the horn buds. You cannot keep mature dairy goat bucks in suburban areas without annoying your downwind neighbors. The worst smell comes from the Swiss-type bucks in the fall and winter, and it is a combination of stale urine smell and musk from the head glands. Bucks urinate on their faces, beards, and legs and produce more of the musk in the fall. There is only one way of truly descenting a buck, and that is to castrate him. "Descenting" is a misnomer. There is no way of stopping a mature buck from reeking of urine. Destruction of the glands on the head is done with the hope that it might reduce the musk smell; it will not eliminate it. Some owners do not want this, reasoning that does might prefer to be bred by the best pheromone producers. Others solve the problem by using yearling bucks, which do not reek as badly, and the ultimate solution is an artificial insemination tank. "Descenting" Buck Kids at the Time of Disbudding Move the iron back and cauterize on a semicircle behind and medial to the disbudding area (Fig. 9). Five seconds per site should be adequate. The consensus among goat owners is that the bucks done this way "smell less" when mature. Adult Bucks The two musk glands on the top of the head are located behind the horn area, buried deep in the folded hypertrophied skin. The gland opening is hairless, at the bottom of a fold. If you are to attempt removal, anesthetize the buck and make a cut around approximately three quarters of an inch away from the crescent-shaped hairless opening. Cut the skin down to the bone and

"Descenting" site

"Disbudding" site

Figure 9. Position of iron for "descenting" after disbudding.

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dissect it free. Examine the tissue and slice it to see whether you have been cutting through connective tissue, which is white, or glandular tissue, which is yellowish. If necessary, remove more skin. It is difficult to close the gap, because the skin is very thick and attached to the bone. At best, you can hope for a reduction in the smell. This is not a recommended routine procedure.

DEWATTLING Many goat breeders believe that wattles detract from the appearance of a show goat, and it is difficult to show clip the hair from them evenly and smoothly, so the wattles are removed at birth. Pull on the wattle and cut at the base with a pair of curved scissors. There is a fibrous core and sometimes a blood vessel that may need to be pinched. Sutures are not necessary.

TEAT EXAMINATION OF NEWBORNS At the time of birth and again at disbudding, all goats should be examined for presence of supernumerary teats, spur teats, fish tail teats, and double orifices. This should be done in bright light by a person with good eyesight and a witness. This is the only way to prove that double orifices and extra teats do not "appear after the kid is born," as is commonly stated by chagrined owners. Although it is technically possible to perform cosmetic surgery on kids, the true test will come when the doe's udder develops. Goats often have glandular tissue attached to spare teats, so when the goat freshens, the gland with no exit will be very obvious. In addition, there is the ethical problem of registering an animal that has had a defect corrected.

INJECTIONS Because sheep and goats are food animals with a short time from birth to meat, injection sites should be chosen with care. My preference for subcutaneous injection is the neck. In young lambs, if there is any reaction, you can see it and deal with it, and in adult ewes coming down a raceway, the neck is readily accessible. Intramuscular injections can be given in the neck or shoulder muscle for the same reasons. Sheep should not be injected when they are wet, because this increases the number of injection site reactions. Clostridial vaccines produce marked tissue reaction and palpable swellings. 5 In dairy goats that are show animals, these vaccines should be placed in a site that is not obvious, e.g., the brisket. Visible lumps on goats could be considered as evidence of caseous lymphadenitis, and this could cause rejection from a show. Injections of some anthelmintics, as with extra-label use, should be done with the knowledge that sometimes animals will react strangely. Goats given levamisole may froth at the mouth, and an occasional individual may appear to hallucinate, looking at something that is not there (C.S.F. Williams, personal experience). Ivermectin sometimes appears to cause severe pain for a minute or two, and sheep may jump up and fall over backward in the chute (C.S.F. Williams, personal experience).

ROUTINE SHEEP AND GoAT PROCEDURES

755

CONDITION SCORING Condition scoringll of ewes is used to improve productivity and manage feed resources. Ewes ovulate the most at a condition score of 3 to 3.5 and should be at least at this score by lambing. Thin ewes and very fat ewes ovulate less. To score ewes, palpate the lumbar spine by running the thumb down the dorsal processes and feeling the lateral processes with the fingers. Scores are assigned as follow: 1 = Each dorsal spinous process and each transverse process has a distinct sharp end. 2 = Dorsal spinous processes are in a smooth line with deep undulations. Transverse processes have smooth round ends. Lumbar muscle concave. 3 = Spinous processes are joined in a line with slightly detectable undulations. Transverse processes are well covered, and you have to push firmly to get your fingers under the edge. Lumbar muscles are not concave nor convex. 4 = The dorsal spinous process line is straight and only detectable with firm pressure. Transverse process ends cannot be felt; nor can you get your fingers under them. Lumbar muscles are convex, with a thick fat cover. 5 = The ewe is so fat there is a dip down the middle of the back. NEWBORN TECHNIQUES Artificial Respiration Lambs that are born with a heart beat but that will not breathe, in spite of chemical or physical stimulation, should be treated rapidly with a respirator. The one developed by Weaver and Angell-James l6 consists of a 9.5-cm tube that extends from the pharynx to the muzzle. A flange then covers the muzzle. Outside this there is a one-way valve, and then a milking machine inflation liner for a mouth piece. Hold your hand around the muzzle to create an airtight fit, and blow down the tube at 20 breaths per minute. Every 3 minutes, wait 15 seconds to see if respiration starts spontaneously. Another technique involves attaching a short mouth piece to a stomach tube. 15 Pass the stomach tube down the esophagus until you can feel the end of the tube in the upper neck region. Pinch off the esophagus directly below the end of the tube. Then blow into the mouth piece, with the lamb's mouth tightly closed. Air will travel back up the esophagus and down the trachea, and it will inflate the lungs. This is a three-handed technique, unless you can hold the mouth piece in your teeth. This technique avoids you blowing up the stomach instead of the lungs. Direct mouth-to-mouth resuscitation of weak lambs should be avoided for zoonotic reasons, e.g., chlamydia, Q-fever, and Salmonella spp. Lambs that will not breathe and that are more than 7 days premature will not have developed sufficient surfactant to prevent spontaneous pulmonary collapse after artificial inflation. 16 Lambs born via cesarian-section, earlier than 135 days, do not survive well. Lambs that have been born as a result of spontaneous premature or dexamethasone-induced labor may have a better chance of survival, especially if they breathe spontaneously. A half-Finn lamb, twin to a mummy, has survived being aborted spontaneously at 129 days (C.S.F. Williams, personal experience). If you are interested in estimating the age of premature lambs, the following rule of thumb is helpful. 9 Lambs that reach 105 days' gestation will have wool on the head and neck only. By 115 days there is wool growth over all the rib cage area. By 125 days there is wool allover the body, but it is short and straight, like white velvet, over the thighs. By 135 days all the wool on the body has crimp in it.

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Treatment of Hypothermic Lambs Although most shepherds can tell whether a newborn lamb is in good shape by sticking a finger in its mouth ("hot" = OK, "warm" = worth watching, "cold" = desperate action required), no one can tell how low the temperature actually is. A rectal thermometer is very helpful, because the treatment varies with the level of hypothermia and the age of the lamb. 4 The following situations will illustrate. Situation 1: Lamb temperature is 37° to 39° C. Age is unimportant. If the lamb is wet from rain or birth fluids, dry it first. Then feed it and put it in a sheltered place with its mother. Situation 2: Temperature is less than 37° C and the lamb is less than 5 hours old. Dry it, warm it, and feed it. Situation 3: Temperature is less than 37° C and the lamb is more than 5 hours old and able to hold its head up. Stomach tube it, dry it, warm it, feed it again, and return it to a sheltered place. Situation 4: Temperature is less than 37° C, and the lamb is more than 5 hours old and is so weak it cannot hold its head up. Do not warm this lamb until it has received 10 mL/kg of 20% dextrose solution intraperitoneally. Then warm it. Stomach tube it when it can lift its head and sit up, not before. If you warm these comatose lambs without prior glucose therapy, they will suffer severe brain damage and few will survive. To make 20% dextrose, use 10 cc 50% dextrose + 20 cc 5% dextrose = 30 cc 20%, OR 10 cc 50% dextrose + 15 cc water = 25 cc 20%. To inject a weak lamb intraperitoneally, hold the lamb up by its front legs, so its back is against your legs. Apply 70% alcohol to

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Converted sock

Figure 10. Construction of lamb "sweaters."

757

ROUTINE SHEEP AND GOAT PROCEDURES

an area 1 inch posterior to the navel and 0.5 inch lateral to the midline, on the right side if you are right-handed. Inject the dextrose with a I-inch needle, aiming toward the rump. Warming is best accomplished in controlled-temperature hot air boxes, rather than with heat lamps, which pose a fire hazard and may cause hyperthermia or skin burns if the lamb is comatose at first. When dealing with these various situations, it is important that the treatments be carried out in the proper sequence. Colostrum The amount of ewe colostrum that a lamb needs in the first 18 hours of life to prevent hypothermia is 180 mL/kg in a still, dry 0 to 10 C environment. It is 210 mL/kg if there is rain and wind, at 0 to 10 C. It is much less than what lambs will drink to appetite, which is 267 mLjkg in 18 hours.7 Lambs usually become hypothermic because there is not enough colostrum available or because serious events transpire that cause lambs to voluntarily reduce intake (rejection, jumpy mother, blocked teats, difficulty finding teats, painful entropion, early castration/docking, and so on). If newborn lambs are given lamb "sweaters" to wear (Fig. 10), the incidence of hypothermia is greatly reduced, and the speed at which it progresses to a crisis is slowed. These "sweaters" are especially valuable when prolific ewes deliver low-body-weight lambs in cold climates (C.S.F. Williams, personal experience). If you also stomach tube all triplets and low-body-weight twins with 50 mL of colostrum as soon as they are born, you will be "putting some gas in the tank" and they will usually progress on their own. However, if you fill them up, they will go to sleep instead of going through teat sucking behavior and establishing good mother-offspring bonding. Too much bottle feeding encourages lamb-bottle-human bonding. For maintenance, lambs need 120 mLjkg/day of high-energy feed divided into two or three feeds. Tiny lambs benefit from more frequent feeding. Ewe milk is 6% to 8% fat, and ewe milk replacers are high fat compounds. Lambs can be raised on cow milk, but they will never be fat while drinking 3.25% fat milk. Cow colostrum is also lower in energy than ewe colostrum, and lambs need more of it to supply their caloric requirements in the first 18 hours of life. 7 To collect colostrum from ewes in much greater amounts than you can get by hand-milking alone, administer oxytocin 5 IU IV followed by a I-minute wait, or 10 to 15 IU 1M followed by a 3-minute wait, and this will enable you to milk out about six times more than normally available. 0

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0

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REFERENCES 1. Black-Drummond S: Angora Goats the Northern Way, ed 2. Freeport, Michigan,

Lonesome Farm, 1988 2. Buttle H, Mowlem A, Mews A: Disbudding and dehorning of goats. In Practice 8(2):63-65, 1986 3. Eales A: Feeding lambs by stomach tube. In Practice 9(1):18-20, 1987 4. Eales FA, Small J: Practical Lambing. A Guide to Veterinary Care at Lambing. Longman, 1986 5. Green DS, Green MJ, Hillyer MH, et al: Injection site reactions and antibody responses in sheep and goats after the use of multivalent clostridial vaccines. Vet Rec 120:435-439, 1987 6. Lester WA, Benson R, Froehlich P: Lamb resuscitation. Vet Rec 126:296-297, 1990 7. Mellor DJ, Murray L: Making the most of colostrum at lambing. Vet Rec 118:351353, 1986

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8. Mellor DJ, Murray L: Stress in lambs due to castration and tail docking. Res Vet Sci 46:387, 1989 9. Orr M: Estimation of gestational age oflambs based on fleece development. NZ Vet J 33:99,1985 10. Rodick BJ: A one-man sheep-bleeding technique. NZ Vet J 6:20, 1958 11. Russel A: Body condition scoring of sheep. In Practice 6(3}:91-93, 1984 12. Sheep Housing & Equipment Handbook, ed 3. Ames, IA Midwest Plan Service, 1982 13. Sheep Production Handbook. Denver, CO Sheep Industry Development Program, 1987 14. Vicary J: Discovering the ovine foot. MSc thesis, University College of North Wales, Bangor, Wales, 1988 15. Vicary J: The six-cut system. The Sheep Farmer Oct:22-23, 1989 16. Weaver BMQ, Angell-James J: A simple device for respiratory resuscitation of newborn calves and lambs. Vet Rec 119:86-88, 1986

Address reprint requests to Christine S. F. Williams, BVSc, MRCVS University Laboratory Animal Resources Michigan State University CI00 Clinical Center East Lansing, MI 48824-1313