TABLE OF CONTENTS Farm Resources Facilities and Equipment Considerations Before Purchasing Arch Frame Buildings Recommended Code of Practice for the Care and Handling of Sheep Use Sheep Behaviour to Your Advantage Herding Dogs Catching and Tipping Sheep Hoof Trimming Preparing for Shearing Ventilation Basics for Sheep Wintertime Ventilation Needs of Sheep Housing Plans Lamb Carcass Bruising Caused By Grabbing Fleece
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Farm Resources, Facilities and Equipment Adapted from ‘Evaluating Farm Resources and Sheep Production Systems’ by Bill McCutcheon, Former OMAFRA Sheep Specialist and ‘Housing and Equipment’ by Ian Alton, Former OSMA Director Labour Labour is an essential and important input in a sheep enterprise. If you are too busy to implement proper flock health and to monitor your sheep closely, the productivity and profitability of your flock will suffer. The amount of labour required will depend on your production system, the size of the flock, amount of cropping, degree of mechanization, facility design, and handling system. When evaluating labour requirements consider the distribution of activities on your farm throughout the year. For example, producers with accelerated lambing programs will generally have a higher, but steadier level of work through the year, while operations that lamb once per year will have increased labour during lambing. Producers who produce their own feed will have extra requirements during haying and cropping seasons. The degree of mechanization generally needs to increase if labour requirements are to remain the same as the size of the flock increases. Such things as feeding with large round bales, using selfdispensing grain feeders, and using tractors to clean pens will greatly reduce time requirements, but must be weighed against extra overhead costs. Whatever your feeding and management systems, however, always consider ways of setting up your facilities to make your work easier. Never create extra work by having things in inaccessible locations, or by trying to work through the stock to reach feeders or other pens. The merits of a good handling system cannot be stressed enough for decreasing labour requirements and encouraging proper flock care.
Land The amount of land you will need depends on whether you plan to produce winter feed for your flock and the level of confinement (i.e. grazing requirements) of the flock. The productivity of the land must also be evaluated to determine the carrying capacity (animals/acre) and the estimated yield from crop production. As this varies greatly throughout the province, it is advisable to contact an OMAFRA Sheep or Pasture Specialist to find out more about your area. Many producers are under the impression that you must own land to be a farmer or raise sheep. In many cases, unless you already own the land, it is likely most economical to rent your land and buildings. The extra debt load imposed on the farming business by buying land may be enough to make the farm business unsuccessful. Unless you have an off-farm source of income to pay for the farm mortgage, renting may be the most viable alternative.
Machinery What equipment do you need to operate a sheep enterprise? If you pasture your sheep you may need equipment to clip pastures for weed control and to spread fertilizer. Unless you are over-wintering your sheep on pasture, you will need to remove manure from the sheep barn and yards. The equipment needed for this could consist of a 40 to 65 h.p. tractor with a front end loader, a rotary mower, and perhaps a manure spreader. If you are going to be producing winter feed on-farm, baling and combining equipment will also be needed. It may be cheaper to buy your hay and grain than produce it yourself when you consider the cost of the equipment and labour required. If forage and grain are purchased off the farm, the shepherd has the opportunity to expand the flock by using more land for pasture. Hiring custom operators with their own equipment to crop your land may also be a viable alternative.
Housing Sheep do not require elaborate housing. Although extra considerations must be made for young stock and during lambing, adult sheep do not require a warm barn and can thrive if they are provided with a draft free place to get out of the snow and wind. Remember that animals housed outdoors during winter will have to put energy resources towards maintaining body temperature and, therefore, will have greater nutritional requirements. During periods of high production demands such as lactation or growth, the animal may not be able to eat enough to supply these needs, so production and body condition will suffer. When housing outdoors during the summer, do not neglect to provide shade for animals. When housing indoors, space requirements including floor space and feeder space must be evaluated to determine how many sheep can be housed in a given pen. The most important things to consider when assessing housing facilities are: • Adequate floor space for the number of animals to be housed. Ewes require 10-20 square feet depending on the stage of production. (See The Code of Practice recommendations at the back of this binder) • The ease of feeding, cleaning, and handling the flock • Ventilation and drainage
Lambing Facilities Lambs are born with little fat cover and a low energy reserve. Hypothermia is the main cause of lamb loss in Ontario and lambs that are exposed to cold, wet conditions are very vulnerable. Therefore, an insulated area is a must if you are lambing in the winter. Once lambs are dried off and have a good start, they are better able to handle lower temperatures. Many producers will isolate ewes with newborn lambs into mothering pens for a day or two. The purpose of these pens is to allow the ewe to calmly accept her lamb in safe and stress free environment. This may be particularly important for ewes the first time that they lamb, as they are more likely to reject the lamb(s). As well, other ewes that are close to lambing themselves may attempt to ‘steal’ newborns. Pens should be clean, easily disinfected, draft free and constructed so that lambs cannot become chilled or trapped. They should be no less than 4’ x 5’ in floor size and at least 30” high.
Ventilation Ventilating barns properly is an important and at times challenging aspect of maintaining a healthy flock. Viruses and bacteria thrive in low quality air and can cause respiratory diseases in animals. This is a particular problem for young stock, which are more prone to pneumonia resulting in poor growth and high mortality. When livestock are housed in barns the air should be kept clear of excess humidity and heavy odours. This is complicated by the fact that by-products of forage digestion are water and heat, and a flock of sheep can produce very humid conditions in a barn in a short period of time. The purpose of a ventilation system, therefore, is to replace the moist, warm air inside the barn with cool, dry air from outside. Providing adequate ventilation during the winter is a balance of circulating enough outside air to keep humidity down, while maintaining adequate warmth (e.g. prevent water lines from freezing, protect lambs, etc). Ventilation during the summer may be even more problematic if the outside humidity equals that within the barn. Barns can be ventilated naturally or by forced air fans. Open style barns are usually well enough ventilated but some of the larger ones require more elaborate systems to get air circulating through all areas. For closed barns, opening windows away from the wind will help solve the problem, but take care to prevent drafts directly onto the animals during the winter. Reducing stocking density, shearing animals, and providing dry bedding will help avoid problems with humidity in both the summer and winter. To learn about specific types of ventilation systems or if you are in doubt about the ventilation capacities of your barn, contact your provincial specialist to arrange a consultation.
Flooring Floors are typically either earth or cement. Earth floors are warmer, softer, and more economical, but may be hard to maintain. Good drainage is needed to keep the floor dry. Concrete floors are very hard and unforgiving, but are easy to maintain and sanitize. Plenty of clean, fresh bedding should be provided at all times. If it isn’t clean enough or bedded well enough for the shepherd to curl up on, then it isn’t adequate for the flock either.
Penning Ideally sheep should be divided into group pens according to nutritional requirements. This allows the shepherd to meet the nutritional needs of the animals as closely and economically as possible. Animals may be penned according to the following groups: • open/dry ewes on maintenance diet • rams • ewes preparing for breeding (flushing) • type of pregnancy (i.e. single or multiple pregnancy; if pregnancy testing performed) • ewes with newborn lambs • lactation demands (e.g. number of lambs, stage of lactation) • market lambs based on age, weight, and/or finish • replacement ewe and/or ram lambs (may feed differently than market lambs)
Feeding Sheep should be fed in a manner that does not require the shepherd to enter the pen with the flock. Walk-through (feeder divides two pens, allowing producer to feed both pens) or bunk feeders accessible from alleys should be used. Adequate bunk space must be provided to allow all sheep to eat at the same time with some space left over. This allows smaller, more submissive animals to eat at the same rate as the rest of the flock. This helps maintain an ideal average body condition in the pen, and helps decrease the incidence of overeating disorder in feeder lambs There are various styles of feeders available. Feeders should be designed to keep sheep from walking on the feed and to prevent feed from being pulled onto the ground. This helps keep feed clean to minimize parasite loads and decrease feed wastage. Commercially produced feeders will last longest, but for economic reasons adequate feeders can be made from wood.
Feed Storage Grain must be kept dry (i.e. off the ground and protected from the elements). Grain that gets wet is prone to developing moulds, which are potentially harmful to the sheep. Grain should also be protected from rodent infestation as much as possible. Protecting hay from moisture and sunlight helps to maintain nutrient quality and prevents wastage.
Watering Where possible, automatic watering devices should be provided. In cold barns you may have to consider heated automatic bowls and insulated or heated pipes. Approximately 40 ewes, 10 rams, or 5075 feeder lambs can use one watering bowl. Water is the most important and often the most overlooked nutrient in a sheep’s diet. Sheep do not like dirty water and will consume more if it is not fouled. Bowls should be checked daily and cleaned when needed. A quick scoop that only takes a second will clear the bowl of hay, straw, or manure. If you are using ponds or dugouts as a water source, watch for build up of blue-green algae. This alga can be potentially fatal to livestock and humans.
Manure Storage Store manure away from buildings and corrals to prevent run-off into sheep housing areas, water sources, and feed supplies. Take precautions when spreading manure to prevent contamination of water sources and oversupplying nutrients to soil. New provincial regulations regarding the handling and storage of manure will soon be in place. Contact OMAFRA to learn about these regulations and how to implement a nutrient management plan on your farm.
Canada Plan Service Canada Plan Service (CPS) is a nationwide network of agricultural engineers and livestock specialists concerned with the planning, design and construction of modern farm buildings. Their goal is to gather ideas from across Canada and then develop construction and management recommendations. In this way, up-to-date building technology and farmstead management practices are available to all Canadian farmers. Ten technical committees, with membership drawn from each province, develop the Canada Plan Service publications. Publications take the form of detailed construction plans or management and construction leaflets. Each province distributes the plans and leaflets according to its needs. (See their website (www.cps.gov.on.ca or contact OMAFRA (1-519-826-3100) for information on how to order building plans).
The CPS Information Resource focuses on the following areas: 1. Farm Structures and their Environments 2. Waste Handling and Storage 3. Animal Care and Comfort 4. Crop Handling, Storage, Processing and Conditioning 5. Rural Environment 6. Systems Engineering A few of the plans available specifically for sheep housing and handling include: • Pole frame sheep shed • Slotted floor sheep barn • Sheep drylot unit • Shearing floor and fleece-sorting table • 6-sided sheep feeder • Adjustable feed bunk • Mineral boxes • Lamb creep feeders • Feed rack • Fence line and walk through feeders • Sheep corral fencing and gates • Loading chute
Building or renovating When a decision is made to construct or make modifications to a farm building, new building code regulations must be considered. Farm building construction in Ontario is primarily regulated by the Ontario Building Code 1990. This code, proclaimed on October 1, 1990, recognizes farm buildings to a larger extent than previous Ontario Building Codes. It is necessary to obtain a building permit for all
agricultural construction projects in Ontario. Manure storage, grain bins and silos all fall into the definition of "farm buildings", and along with all other farm structures, will require building permits.
Farmstead Planning When planning a new building or adding to an existing farmstead, you must consider such things as: • Site drainage • Services (lanes, power, water supply, waste disposal: • Security • Separation distances for snow and wind control, ventilation and disease control • Distance separation from residences for control of noise and odours • Municipal Regulations Office of the Ontario Ministry of Agriculture, Food and Rural Affairs can provide many Factsheets and other publications pertaining to the planning of farm buildings, manure storage, etc. Check with your local municipality and OMAFRA early in the planning stage. The construction of livestock facilities is usually only permitted in agricultural zones. In addition, the location of the facilities is often restricted by setback distances from roads, lot lines, neighbouring houses and land uses. Usually these setback distances are based on the Agricultural Code of Practice and take into account: • Number of animals on the site. • Type of livestock • Management system • Degree of expansion • Manure storage
Considerations Before Purchasing Arch Frame Buildings By: Robert Chambers P. Eng Engineer, Swine and Sheep Housing and Equipment OMAFRA (Ontario Sheep News, March 2010) Pre-engineered buildings such as fabric covered arch-framed buildings or hoop barns, are common in Ontario’s Agricultural Community. These structures are used for hay, machinery and manure storages as well to house sheep. Properly engineered, constructed and maintained they can offer years of useful economic service. These buildings are not considered to be temporary buildings. A Building Permit is required and if used for livestock housing for more than 5 Nutrient Units (40 meat ewes or 100 Feeder Lambs) or as manure storages they will require a NMS (Nutrient Management Strategy) approved by OMAFRA and if greater than 300 Nutrient Units an approved NMP (Nutrient Management Plan) as well. The NMS and NMP must be prepared by a certified person. In unorganized municipalities where there may be no building permit requirements, a NMS must still be prepared and kept on the farm. Livestock housing and manure storages will also be required to be set back from conflicting land uses as per the Minimum Distance Separation formula, even for capacities less than 5 Nutrient Units. It is also required to file an engineering design with the municipal building official as well if deemed necessary by the official. Arch Frame structures are subjected to the same snow and wind loads as other types of buildings and should be designed as such. In order for a Farm Building to qualify as a Greenhouse and allowed designed uniform snow load of 0.7 kPa (14.6 lbs/ft2) it MUST have a heating and drainage system installed specifically to prevent the accumulation of snow. Having the building occupied by animals or having a clear plastic covering does NOT qualify as a heating system. These types of structures due to their profile can be subjected to unbalanced loading (accumulation on one side of the structure from drifting and sliding snow and ice) as well. This pile of snow and ice in extreme cases if not designed for, can create significant pressures pushing in on the wall of the structure. These buildings should be located away from other structures such as barns and silos where snow and ice could slide off and onto the roof of the hoop barn. Arch Frame buildings are commonly constructed on two types of foundation systems, On Grade and On Posts. Both systems have their advantages and disadvantages. On Grade systems have the steel frames anchored directly to the concrete floor. This provides the best support for the structure as the horizontal forces generated by the roof loads are carried
by the concrete floor. The disadvantage of these systems is that the roof covering must be protected from livestock damage. On Post systems are favored as they provide a more usable height along the wall. Since the steel frames impose a significant outward thrust on these posts, there must be some features designed so as to counter act these forces. The higher the wall, the more significant these forces become. Often designers use tie rods connecting the two sides of the building encased in a concrete filled trench under the floor to counteract these forces. Wind causes both uplift and lateral loading on buildings. As the wind moves up and over the top of a structure it generates significant uplift forces. Typically, the net uplift in a 1 year in 10 design wind can be in the range of 4.2 to 8.4 lbs/ft2. For example a building 27’ by 50’ could potentially have an uplift force of 11, 250 lbs, and this can double for short periods due to gusting. If this force has not been accommodated in the design and construction of the building, there is a significant risk of total failure. Lateral wind loads that try to push the structure over must also be designed for as well. The use of diagonal cables and structural members is commonly used to perform this function. Further more the tarp covering must be tightened regularly to insure that it is not damaged by flapping in the wind. In summary, fabric covered arch framed structures for farm buildings are subject to same building codes and engineering design principles as all other farm buildings. More importantly, for a safe environment for yourself and your animals and a useful structure for the future ensure that the building is properly designed, constructed and maintained for the purpose that it is intended for. This article was adapted from a factsheet on Plastic and Fabric Covered Arch Frame Buildings written by Harold House, Harry Huffman and John Johnson
USE SHEEP BEHAVIOUR TO YOUR ADVANTAGE Producers who understand sheep behaviour can use this knowledge to their advantage in all aspects of sheep production and management. Whether setting up and using handling and shearing facilities, moving the flock to a new pasture, or catching an individual sheep, taking their behaviour into account ensures the job is completed in an efficient, low-stress manner. Some important aspects of sheep behaviour as it relates to handling and movement include: • • • • • • • • • • • • • • •
Sheep do not like to be enclosed in a tight environment and will move on their own accord into larger areas. Sheep move toward other sheep willingly. Sheep move away from workers and dogs. Sheep have good long-term memory (relative) especially with respect to unpleasant experiences. If given a choice, sheep prefer to move over flat areas rather than up an incline, and up an incline rather than moving down it. Sheep prefer to move from a darkened area towards a lighter area, but avoid contrasts in light. Sheep flow better through facilities if the same paths and flow directions are used every time. Stationary sheep are motivated to move by the sight of sheep running (away). Sheep will balk or stop forward movement when they see sheep moving in the opposite direction. Sheep will move faster through a long, narrow pen or area than through a square pen. Sheep move better through the handling chute (race) if they cannot see the operator. Sheep will more willingly move toward an open area than toward what they perceive as a dead end. Very young lambs that become separated from their dams will want to return to the area where they first became separated. Sheep react negatively (as do all livestock) to loud noises, yelling and barking. Young sheep move through facilities easier when their first move through is with welltrained older sheep.
Many years of observation by people who work with sheep under a wide range of conditions have gone into establishing the above-listed points of sheep behaviour. They illustrate that certain actions and reactions by sheep are very predictable, and can be used to the producer’s advantage in all aspects of sheep management. Those producers who incorporate aspects of sheep behaviour into management of their flock will see positive results in the ease of moving groups, willingness of sheep to enter and be processed in handling facilities, and fewer stress indicators in the animals and handlers.
By Anita O’Brien, Sheep and Goat Specialist, OMAF, Kemptville. For more facts about sheep and many other useful factsheets go to www.omafra.gov.on.ca/english/rural/facts
Herding Dogs
A well-trained dog can save a producer a great deal of effort when herding and moving sheep. Many breeds of dogs are used on sheep farms throughout the world. In Canada, the black (or brown) and white Border Collie is perhaps the most popular. In selecting a dog, make enquiries, watch sheep dog trials and, if possible, enlist the aid of an experienced handler. A purebred dog is by no means essential, but a well-trained dog is. Most breeds of herding dogs have strong instincts to stalk and chase livestock. If these instincts have not been properly channeled through training, dogs will generally do more harm than good by chasing sheep in the wrong direction, running through the flock, or becoming overly aggressive towards the sheep. Even with well-trained dogs (depending on their temperament), you may wish to restrict their use to gathering sheep in large areas, rather than in small pens or handling systems. Dogs may become overly excited with sheep in confined areas, particularly if the flock is not moving well. The sheep will remember the frightening experience and may be reluctant to enter the handling system the next time. If you buy a professionally trained dog, be sure to take some time to learn commands that the dog will understand; improperly trained people may be just as frustrating for dogs, as poorly trained dogs are to shepherds.
Catching and Tipping Sheep By: Les Jones; Former OMAFRA Sheep Technician (Modified by OSMA 2010) Catching Sheep At times it is necessary to catch and handle individual animals. If you do not have a handling system and have to catch sheep in a pen, use gates or hurdles to make the pen as small as possible. Do not get into the habit of chasing sheep around a pen. This is not only tiring, but is potentially dangerous for the sheep and the person trying to catch them. Compared to horses or cattle, sheep are not large animals, however, they are very fast on their feet and very strong for their size. Many people have been injured by trying to catch a sheep improperly. Repeatedly chasing your sheep will also make them flighty and difficult to work with. Manoeuvre the sheep into a corner, extending your arms or using a portable gate to form a visual barrier. Approach the sheep slowly and calmly. The sheep will likely attempt to escape but will probably not move away from the wall, so its moves can be anticipated. To properly catch a sheep, reach for one of three places. •
Under the chin: Approach the sheep between its shoulder and flank (if you approach too close to the head, the sheep will likely be able to duck away from you). Cup your hand under the chin and point the nose up to stop the forward motion. Be sure that you get your hand on the bony part of the jaw, not on the throat or you will think you have caught a horse and will be dragged around the pen. Place your other hand on the tail/rump to prevent the sheep from backing away from your hand on its chin. If you are near a wall, you may wish to gently push the sheep against the wall to prevent sideways movement.
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Hind leg: Catch the animal by one hind leg, positioning your hand just above the hock. Move your other hand up to control the head as soon as possible. As adult sheep are still able to kick strongly while being held just by the leg, this method generally works best for young, lightweight animals.
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The Flank: Catch the animal by the front part of the hind leg as near as possible to the body. Place your free hand up to the head as soon as possible. If you control the head the rest of the animal will stay there as well. Whichever method you use, remember that the wool is not a handle and should not be used as a means of controlling the sheep. This is particularly important when handling animals near slaughter weight, as wool pulling is a significant cause of muscle bruising and meat wastage. To move the sheep lift the tail and let the head down a little, and anticipate that the animal may try to bolt.
Tipping or Turning Sheep Once the animal is caught, you may wish to ‘tip’ the sheep onto its rump to trim feet, inspect the udder etc. Surprisingly, sheep in this position struggle very little and are generally easy to work with (Figure 1). There are a few methods of getting the sheep into this position. Depending on your preferences, the following method is generally the least tiring and easiest on the handler and the sheep. These instructions are for a right-handed person, if you are left-handed you will likely find it easier if you reverse the directions.
1. Starting position: • Stand the sheep in front of you • Hold the sheep’s head in your left hand, placing your hand under the jaw • Your left knee should be near or just behind the sheep’s left shoulder • Your right leg should be touching the sheep’s side near its left hip • Your right hand on the sheep’s back over the hips 2. Turn the sheep’s nose away from you and right around as if it was trying to reach a spot on its back just behind the shoulder. As soon as you bring the nose around you will feel the weight of the sheep lean against your legs. 3. Put enough pressure on the hips with your right hand that the sheep cannot pick its back feet off the floor. Take a step back with your right leg (your back not the sheep’s!). The hind end of the sheep will start to go down. 4. Continue to bring the head around until the animal is sitting down with its back leaning against your legs. Steps 2-4 should be done in a smooth motion. The mistake most often made by beginners using this method is to move the wrong foot. Remember to pivot on your left foot and step behind you with the right foot.
Hoof Trimming By: Dr. Cathy Gallivan, PhD: ‘Sheep Canada’ Summer 2002 (Modified by OSMA, 2010) Sooner or later most shepherds have to trim a few feet. The frequency of this job varies with the breed of sheep and the environment in which they are kept. In an extensive grazing environment, where sheep are required to walk long distances, hooves wear down naturally and generally require little trimming. Sheep housed in smaller areas or in pastures with soft, wet ground may require trimming at least once or twice a year. Sheep that are housed on manure packs, for instance, may require more hoof care. The rate of hoof growth varies to some extent with the breed. Some breeds, such as Rambouillet, have been selected for their ability to travel long distances in very extensive grazing conditions. These breeds have feet that grow faster than other breeds commonly found in farm flocks grazing smaller areas, and may require more trimming. The other major difference between breeds is the hardness of their feet. Sheep with white feet generally have hooves that are softer and easier to trim than breeds with black feet. This is another example of breeds being adapted for a particular environment, as many of the breeds with black feet (such as the Suffolk or Hampshire) originated in parts of the UK where the ground may be soft and wet. Regardless of colour, sheep feet are softer and easier to trim when the sheep have been standing on soft or wet ground (e.g. late spring) than they will be after standing on hard dry ground (e.g. mid-summer). Shepherds planning to trim the whole flock in one session would be well-advised to plan the event to coincide with a period when the feet will be softer and easier to trim. In some flocks, foot trimming is done at least once a year on all animals, often before they are turned out onto summer pasture. However, a recent survey of sheep producers in Alberta revealed that many flock owners simply monitor the hoof condition of their sheep and trim individual animals as required. There are a number of foot trimming tools available that are specifically designed for trimming sheep. The type of design you choose is a matter of personnel preference. Some have handles that roll back and forth to make it easier on the operators hands. Some have serrated blades and some blades are plain. Lighterweight pruning shears are cheaper and may be suitable for small flocks, but won’t stand up to trimming hundreds of animal’s feet. The typical method involves catching, tipping, trimming all four feet and then releasing the sheep. Every shepherd will develop his or her own style of hoof trimming. The diagram below will get you started. Be careful and don’t get frustrated. You’ll get faster as you gain experience. If you make a mistake and cut too deep, don’t panic. It’s a bit like getting a hangnail – it does hurt and it may bleed, but no one ever died of a hangnail. As sheep have gotten bigger and stronger and shepherds older and smarter, a number of operations have turned to tipping tables or crates. Crates are usually placed in the handling system so that a sheep walks down the chute, into the crate, and can then be easily turned on her back for trimming. These crates can considerably speed up the job of foot trimming, and make it so that the shepherd can walk upright when the job is done! Some models require turning the sheep (in the crate) by hand, while others are spring loaded or hydraulically operated. When there are a lot of sheep to be trimmed, feet are particularly hard and dry, or when the use of a tipping table makes it important that the animals be handled quickly, pneumatic hoof trimmers that run off air compressors can also be used to dramatically reduce the time required. For more information regarding the magazine ‘Sheep Canada’ call the toll-free number 1-888-241-5124 or check out their web site www.sheepcanada.com
Trimming Hooves:
Preparing for Shearing By Rick Metheral (Former OSMA Provincial Director) (Modified by OSMA 2010)
Sheep should be shorn at least once a year, to help maintain healthy skin, and to minimize external parasites, wool blindness, and fly strike. Shearing day can be a hectic time in the shepherd’s calendar, but with some careful planning the day should run smoothly.
When to shear: There is not a set time of the year when you should shear, however, there are a few guidelines that may be helpful in determining the best time for your flock: • Producers often have their sheep shorn approximately a month before lambing. Be careful not to wait until the ewes are too heavily pregnant, as this will be stressful for the ewes and awkward for the shearer. Shearing a month before lambing helps keep the fleece clean during lambing. This decreases the chances that lambs will ingest manure by mouthing soiled fleece while searching for the teats. The lamb(s) will also have an easier time finding the teats for the first time if the fleece is short. Some producers may wish to crutch ewes prior to lambing rather than having them completely Photo By: Eadie Steele shorn. • Shearing can reduce heat stress and humidity in the barn. • Bear in mind weather conditions and housing facilities when planning shearing. Cold during the winter and sunburn during the summer can make life unpleasant for freshly shorn sheep. • Shearing while the ewes and lambs are together may cause injury to the lambs and havoc on the shearing floor. • Shearing ewes just after lambs are weaned or during periods of nutritional stress, may make shearing difficult. Talk to your shearer to see if he/she has a preference regarding shearing at this time. • Avoid foot trimming for a few weeks prior to shearing as sharp hooves can cause serious injury to the shearer. • Be sure withdrawal dates have been met for any pour-on medications used on the sheep. The shearer probably doesn’t need to be dewormed and the chemicals may contaminate the wool. • It may not always be possible, but try to avoid performing stressful handling practices, such as needling, deworming, etc, near to the time you are going to shear. The sheep will remember that the last time they were handled was stressful and/or painful, and may become agitated.
Preparing for Shearing: Preparation for shearing should begin at least 3 or 4 months in advance. There is a shortage of professional shearers in Ontario, and their services are generally booked early for the busiest times of the year. Leaving booking until the last minute may mean that the shearer will unavailable. This could seriously disrupt your management schedule and postpone shearing until an inopportune time. Take care of the wool while it is still on the sheep by avoiding throwing hay and straw over the backs of sheep, and by removing any plastic twine from feeds and pens. Contact the Canadian Co-operative Woolgrowers for an updated list of shearers in Ontario. With shearing day booked and fast approaching, begin to get the shearing area ready: • Shear in an area that the sheep are familiar with and normally enter • The shearing area should have:
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Adequate ventilation Good lighting Ready access to a hydro outlet Small catch area if shearing shed not available
You should have available: o Lots of eager help o Clean work area o Disinfectant approved for use on livestock for any nicks and scraps o Plywood; 4 X 8 to shear on o Rolling table for wool (slatted table or grated table to allow second cuts and vegetable matter to fall through when skirting fleeces) o Provisions for coffee breaks and meals Have the sheep inside and dry on the day before the shearer arrives. You will probably have to postpone shearing, if they are wet. Consider holding sheep off feed the night before. This is especially true if they are on an energy rich feed, such as lush grass or grain, as this may cause bloating and discomfort when sheep are tipped for shearing. Holding sheep off feed over night may also help keep the fleeces clean. Sheep should be allowed access to water. Try to separate your animals into groups to minimize the spread of diseases such as Caseous lymphadenitis by shearing healthy animals and/or those less likely to be infected first. This may include shearing young animals before older animals. If infected animals are detected during shearing, ensure the clippers are disinfected prior to shearing
other sheep.
Ventilation Basics for Sheep By: Robert Chambers P. Eng., Engineer, Swine and Sheep, OMAFRA, Fergus (Ontario Sheep News, November / December 2005) As we are moving into cooler weather it is time to review the basics of ventilation to ensure that we get the maximum comfort, and by association, performance from our flock. The vast majority of flocks in Ontario have some sort of shelter for the winter months. Though sheep can tolerate the cold given a proper diet, freezing, and near freezing rain combined with wind can be very detrimental to their health if they have no shelter to escape this type of weather. Every type of structure used to house sheep, or any other animals, relies on ventilation to introduce fresh air and to remove excess moisture, dust, manure gases and to modify the temperature. Moisture and gases are produced by respiration and from the decomposition of the manure pack. Sheep produce two types of heat: sensible or dry heat and latent or heat from the evaporation of moisture (the animals breathe and the manure pack). Latent heat production tends to decrease as the air temperature goes down and sensible heat production goes up. The desired temperature is maintained in the barn by stocking density (more sheep, more heat until welfare is compromised), insulation (more insulation, less heat loss through the building shell) or additional heat (expensive). Fortunately for sheep producers, with the exception of very young stock, sheep are able to withstand a wide range of temperatures as long as they are in a dry and relatively draft free environment. The goal is to have a Relative Humidity in the 50 to 75 % range; in this range condensation on the exterior surfaces is minimized and the animals are in their comfort zone. This can be achieved by means of natural or mechanical systems that are designed to remove air from the building, but also control the incoming air as well. Humidity is removed from the barn by introducing outside air into the barn space, mixing it with the air in the space, and then exhausting it outside. One kg of outside air at -25°C for example can have a volume of 700 litres, a relative humidity of 100% and contains 0.4 grams of water vapour. The air enters the barn airspace and warms up to 15°C and the same kg of air has a volume of 820 litres, a relative humidity of 75% and contains 8 grams of water vapour. It then leaves the barn space via the exhaust system. Thereby, a kg of air at -25°C, 100% relative humidity can remove 7.6 g of water vapour from the airspace at 15°C and a relative humidity of 75%. The type of shelter required depends on the production system. Those producers who lamb only in the early fall or late spring / summer can get by with only a rudimentary shelter, three walls and a roof with the open front to the South, is adequate. Whether it’s a non-insulated pole type structure, hoop barn or steel prefab type building the key to success is to orientate the opening away from the winter winds and towards the south. Animal comfort is reliant on a dry and relatively draft-free environment. The water system must be heated or insulated such to prevent
freezing and the barn temperature is allowed to swing in rhythm with the outside temperature. Any attempt to seal these types of buildings to increase temperature results in very uncomfortable sheep and a rapid deterioration in the structure. It is a recommended practice to insulate under the roofing steel with 0.9 RSI or R5 in order to reduce condensation and to install chimneys or ridge vents. Hoop barns should have a ridge vent or chimneys to exhaust the warm moist air out the top, barring this, the tops of the end wall should be left open so as to allow the humidity to escape, through this technique will be less effective on longer barns. For marketing reasons, many Ontario producers lamb year-round or through the winter, this entails a more complicated type of structure in terms of insulation and/or heating. Lambing pens should be kept about 2°C or greater with provisions of a means of heating sick/orphan pen(s) as the need requires. By placing claiming pens away from outside wall and/or drafts allows for greater comfort of newborns until they are dried off and adapted to their surroundings. In order to maintain a 2°C or greater temperature within the barn itself there is a need for heat and insulation. Heat can come in the form of the animals themselves and if required by the addition of a heater, typically a gas fired radiant tube heater. Insulation levels should be RSI 3.96 (R22.6) for the walls and RSI 5.32 (R30.4) for the ceiling. Again, supplemental heating may be required depending on production practices and the barn location (Lucan vs. Powassan for example). Ventilation rates, either natural or mechanical should range between 1.75 l/s (3.7 cfm) per ewe minimum to 10.1 l/s (21.5 cfm) per ewe maximum. With proper stocking rates, ventilation can maintain a comfortable relative humidity and temperature while minimizing condensation on the exterior surfaces of the barn, through this assumes equal distribution in the barn. Many facilities have proper sizing of inlets and outlets (fans or chimneys), but have “dead pockets” of air that are detrimental to animal and building health. For these situations the addition of stir fans like those used in the poultry industry can aid in the proper distribution of air.
Wintertime Ventilation Needs of Sheep Robert Chambers P.Eng Engineer, Swine and Sheep Housing and Equipment OMAFRA
Sheep that are housed inside during the winter require proper ventilation to obtain their maximum performance potential. Ventilation systems are best designed by a ventilation expert because of the complexity of the various factors involved. Producers though must understand how their system works and how to manage it to obtain optimal animal performance.
The five main environmental factors that are controlled by ventilation are: • Fresh air to breathe • Freedom from drafts • A comfortable room or barn temperature • A reasonable humidity level in the air space • Acceptable levels of contaminants In winter only a small volume of fresh air is required to provide oxygen, reduce humidity, and control odours. Summer ventilation requires large volumes so as to control the temperature. The challenge of any ventilation system is to provide uniform, high quality air throughout the facility. Fan ventilated barns require proper sizing, staging, location, and control of both the inlets and the fans. Natural ventilated barns use the natural forces of wind and thermal buoyancy combined with controllers (automatic or manual) to ventilate. Adjust the ventilation system to eliminate dead air
spaces. If needed, add stir fans to ensure even air distribution throughout the facility. Mature sheep with a full fleece are not susceptible to winter drafts; young lambs are at the other end of the spectrum. Low birth weight lambs, triplet and quadruplets, are often already challenged with lack of body fat reserves. A wet, newborn lamb exposed to a draft is at risk of dying from hypothermia at 100C. A dry, healthy lamb, even a small one, kept away from drafts with a belly full of colostrum can handle temperatures down to -10oC. In older bank barns the major source of drafts are open hay/straw chutes and improperly closed doors. Fan vented facilities can have improperly adjusted air inlets that dump incoming cold air directly on to the lambs. These inlets should be adjusted to jet air along the ceiling so as to mix with the room air, then slowly descend into the animal space. Doors left open can short circuit the ventilation system and cause drafts and pockets of poor quality barn air. Naturally ventilated barns are at the mercy of wind speed and direction for ventilation. Place a 12� windbreak skirt to the eve in front of the inlet or use 30% to 40% porosity shade cloth on the top 12� of opening on the curtain. These techniques allow for minimum ventilation, but reduce the effect of wind gusts and blowing snow. On still, extremely cold days, often a chimney can become an inlet. Condensation and snow can also accumulate underneath the chimneys. Locate lambing pens and young lambs away from these areas. Young lambs prefer to have a solid surface to lie against. Provide solid paneling such as plywood or previously enjoyed plastic penning from the swine industry located away from exterior surfaces. By lying together away from drafts and in dry surroundings, the overall room temperature can be lower, yet still provide a comfortable environment for these young animals. A quick and easy method to determine the presence of drafts is to wet the back of your hand. Most people can sense wind chill on the wetted portion of their hand if the air speed is greater than 50 to 60 feet per minute (0.25 to 0.30 m/s). Place your wetted hand in the area where newborn lambs are and approximately 4 to 6 inches (10 to 15 cm) above the surface; if you can feel a draft on the back of your hand it is too drafty. Mature sheep have a large comfort temperature range. Research from Norway concludes that full fleeced, well fed, healthy mature ewes housed in a dry draft free environment can withstand temperatures as low as -40oC.
Sheep can withstand cold temperatures as long as they are dry. Even a healthy, dried off and fed newborn can withstand temperatures to -10oC provided the environment is dry and draft free, though it is preferable to have a temperature greater then 16oC. The smaller the lamb or the higher the lambing percentage the warmer the barn should be during lambing. Instead of warming the entire barn space, provide a radiant type heating during lambing. A Radiant tube, Radiant brooders or Quartz Electric Radiant types of heaters should be used as they warm the surface of the manure pack, where the lamb is, as opposed to the air space above the lamb. The surface of the pack forms a warm, dry microclimate, which quickly dries and warms the newborn lamb. The main goal with winter ventilation is to control humidity and gasses such as Ammonia and Carbon Dioxide in the barn. The RH (relative humidity) should be ideally maintained between 50% and 75%. If the barn becomes too dry, the lung tissue of the animals can dry out increasing susceptibility to diseases. More often the case though is that barns become too humid, condensation forms on exterior surfaces allowing for the proliferation of molds and funguses that not only impinge on the health of the animals but can also cause equipment and structural deterioration of the barns themselves. The presence of fog throughout the barn indicates a RH of greater than 90%. Humidity is removed from a barn space by the introduction of outside cold air, warming the air by animal heat within the barn with or without supplemental heat to lower the RH of the incoming air. The presence of condensation on exterior surfaces should also be avoided. Moisture is then absorbed by this air raising its RH and exhausted back outside along with gases and dust from the barn space. The major sources of moisture include the animals and the manure pack. A mature ewe with lamb produces 2.2 litres/day and a finishing lamb 0.9 litres/day of humidity through respiration. The manure pack can also be a source of humidity within the barn. Once the manure accumulates to the point where it begins to heat from decomposition, significant moisture as well as Ammonia and Carbon Dioxide can be released. Birthing fluids add a significant amount of moisture to the manure pack, consider a clean out as soon as lambing is completed. Check the watering system to ensure leaks and spillage are kept to a minimum. With a solid manure system every litre of water that enters the barn must exit the barn in the animals produced, the manure or out of the ventilation exhaust. If the surface of the pack is well bedded to reduce the
moisture content of the pack and removed on a frequent basis before heating takes place, the overall air quality can be improved. Consider purchasing a Temperature/Humidity pen that allows the producer to quickly monitor the temperature and RH throughout the barn and identify problem areas. These devices can be obtained for less then $150 from ventilation supply companies. The recommended minimum ventilation rate to control humidity is 10 cfm (cubic feet per minute) per ewe and 3 cfm per feeder lamb. This may have to be increased to 3 and preferably 4 air changes per hour (a complete change of air in the barn every 15 to 20 minutes) to ensure good air quality if the manure pack is heating. Having the ewes shorn is one method to reduce the RH. The sensible heat (the heat that we feel) production can increase by a factor of four by a shorn ewe over a full fleeced ewe. The heat that is produced by the animals raises the temperature of the barn and consequently lowers the RH, thereby providing a greater absorption of the water vapour within the barn space. In an uninsulated structure, more heat is lost to the outside through the exterior surfaces. This lowers the temperature within the barn, thereby lowering the moisture absorption ability of barn air. These uninsulated surfaces are often below the dewpoint (point of condensation) of the room air and condensation on the exterior surfaces results. The recommended minimum insulation level for condensation control is R5 (RSI 0.9). Let’s consider the example of an uninsulated versus and insulated barn (R 5). If the outside temperature is 0oC, the inside temperature is 8oC and the RH is 75% in the barn. From the Psychrometric Chart (ASHRAE 1963) the dew point or the temperature, at which the RH equals 100% (condensation), is 3.3oC. The uninsulated surface will have a temperature of 2oC and will therefore have condensation. The insulated surface temperature will be 7oC and therefore will have no condensation on the surfaces. In conclusion dry sheep are happy sheep. If possible, shear incoming ewes to increase their heat output. If the barn cannot be kept warm through the addition of insulation or supplemental heat, then it is far preferable to increase the ventilation rate so that the RH remains below 75%. Keep the manure pack well bedded and remove it regularly to lower this additional source of moisture and gases.
Particular care must be taken to avoid drafts onto newborn and compromised lambs. Use solid panels to shelter these animals from drafts, and provide supplemental radiant type heat if required. A dry and cold environment out of the drafts is far preferable to wet and warm environment in a cold draft.