Key Points of Black-Boned Sheep Breeding Technology and Feeding Management Methods

I. Grazing and Feeding
　　
(1) Organization of the Flock
Rational organization of the flock not only saves labor but also facilitates flock management. Generally, the flock should be organized according to sex and age, based on the different grazing conditions in different regions.
In pastoral areas and regions with large pasture areas, generally 200 to 250 breeding ewes and replacement ewes form one flock, 150 to 200 castrated fattening rams form one flock, and 80 to 100 stud rams form one flock.
Farming areas generally do not have large pastures; sheep grazing mostly uses field edges, roadsides, forest land, and riverbanks, and grazing is subject to certain restrictions, so flocks should not be too large. 30 to 50 breeding ewes and replacement ewes form one flock, 20 to 40 castrated fattening rams form one flock, and about 10 stud rams form one flock.
In farming-pastoral areas and hilly and mountainous areas, this can be determined according to grazing conditions.
(2) Key Points of Grazing Management in the Four Seasons
① Spring grazing: Because the sheep have gone through the long winter and spring dry-grass season, the sheep are in poor condition and greedy, and are prone to overeating green grass, causing diarrhea, or accidentally eating poisonous plants and being poisoned, or developing bloat (rumen tympany). Therefore, spring grazing must first prevent sheep from "chasing green grass"; second, prevent sheep from "bloating." There is often a saying: "If you graze sheep and hold them back, they will be full of fat; if you graze sheep without holding them back, they will run until they are as thin as a monkey." Spring grazing requires a tight hand; at the beginning, graze on old grass slopes or feed some dry hay first, and then graze on green grass slopes. Spring grass is tender and high in water content, and the mornings are cold, so sheep must not be allowed to eat dew-covered grass, otherwise diarrhea is easily caused.
In spring, after the sheep graze and eat green grass, they should be fed salt once every 5 to 6 days. When feeding, it is best to fry the salt until it is slightly yellow, and add some ground feed that clears heat and stimulates appetite, along with necessary additives. This can help digestion, increase appetite, and supplement nutrition. At the same time, the flock should be given drinking water at least once a day.
② Summer grazing: The climate in summer is characterized by heat, heavy rain, and many mosquitoes and insects, so work to prevent heatstroke and lower body temperature should be done well. During grazing, attention should be paid to going out early and returning late; during the hot midday period, prevent sheep from "huddling together," and let the flock rest in a ventilated, shady place. When necessary, give appropriate rest during grazing. At the same time, do a good job of mosquito prevention and deworming. Give the flock more drinking
water, and appropriately feed some salt.
③ Autumn grazing: In autumn, the sky is high and the air is crisp, forage grass is abundant, and grass seeds gradually mature, so it should be the season when "the whole mountain and plains are good for grazing sheep." Autumn is the season for the flock to build condition and breed. During grazing, pay attention to letting the sheep eat their fill and graze well. This is important not only for winter fattening and marketing, but also for safely overwintering and for sheep reproduction.
④ Winter grazing: In winter, the weather gradually turns cold, plants begin to wither or drop leaves, and there are rain, snow, and frost. During grazing, attention should be paid to cold prevention, warmth keeping, condition maintenance, and protecting lambs. Winter grazing often takes place in front of and behind the village and around the sheep pen, letting the sheep eat some leaves and dry grass. On clear days, let the sheep exercise and bask in the sun more. Pregnant ewes must never be made to cross ditches and ridges. At the same time, the sheep shed should be repaired well; there is a saying that "a warm pen adds three parts of condition."
(3) Matters Needing Attention During Grazing
① Before grazing, the flock should be checked first. If sick sheep are found, they should be kept in the pen for observation and treatment. If ewes in estrus are found, they should be recorded and bred in time, and the number of sheep should be counted so as to have a clear idea.
② Grazing personnel should carry some emergency medicines and instruments, such as ten-drop water for heatstroke, and trocars for releasing gas, etc.
③ When going out to graze and returning from grazing, do not walk too fast. The grazing route should be moderate; do not travel long distances.
④ During grazing, it is strictly forbidden to throw stones at sheep, to prevent the flock from being startled. At the same time, pay attention to preventing attacks by wild animals.
⑤ Do not let the flock eat frozen grass, dew-covered grass, or moldy grass, and do not let them drink sewage. Prevent overeating and overdrinking.
　　
II. Barn Feeding
Boer goats and crossbred sheep are more suitable for barn feeding. Sheep raising in farming areas is also mainly barn feeding, and some is combined with seasonal grazing or "tethered grazing." Sheep farms and specialized households raising flocks all have dedicated sheep sheds and exercise yards, and are equipped with feed troughs and water troughs. The following points should be noted during feeding.
① Fixed time, fixed amount, fixed quality, fixed personnel. Feed the sheep on time so that the sheep form a conditioned reflex, which is beneficial for digestion and absorption. According to different sheep, determine the amount of grass and feed; it should be possible both to eat enough and not waste; ensure feed quality and variety; where conditions permit, formulate mixed daily rations according to feeding standards; feeding personnel should also be relatively fixed.
② Forage, feed, and drinking water must be clean. Do not feed moldy or spoiled forage. Forage must not carry water. In winter, it is best to drink warm water.
③ Keep the sheep shed clean and dry, achieve warmth in winter and coolness in summer, and clean manure frequently.
④ Do a good job of the two annual vaccinations in spring and autumn and routine deworming.
⑤ Do a good job of the usual sanitation and disinfection work on the sheep farm. Sheep manure should be piled, fermented, treated, and then used.
⑥ Increase exercise for the sheep and maintain sheep body hygiene.
　　
1. Feeding Management of Stud Rams
The feeding of stud rams requires feed with high nutritional value, sufficient high-quality protein, vitamin A, vitamin D, and inorganic salts, etc., and it should be easy to digest and good in palatability. Among the more ideal feeds, fresh and dry forage types include alfalfa, clover, sweet potato vines, peanut vines, etc.; concentrates include corn, bran, soybean meal, etc.; others include carrots, pumpkin, malt, bone meal, etc. Animal protein is also very important for stud rams. When breeding or semen collection frequency is relatively high, supplementary feeding of raw eggs, milk, etc. is required.
Boer stud rams should be raised in separate pens. Rams should be grazed in separate groups. Semen should be collected 2 to 3 times a day, and after collection they should be allowed to rest quietly for a while. Stud rams should also undergo regular quarantine, preventive inoculation, and prevention and treatment of internal and external parasites, and attention should be paid to observing their daily mental state.
The Boer goats raised in Lishui County are mainly barn-fed. Rams are grazed combined with exercise for 4 to 6 hours per day. Dry roughage consists of sweet potato vines and peanut vines, provided for free feeding. Each day, mixed concentrate is supplement-fed at 1% of body weight (formula see table). When semen collection is relatively frequent, 2 eggs are supplement-fed each day. Semen is collected 1 to 2 times a day, with one rest every 3 to 4 days. Except when semen quality is relatively poor during especially hot summer and especially cold winter, when semen is not collected, semen quality is relatively good at other times, and semen can be collected almost year-round.
2. Feeding Management of Ewes
(1) Feeding management before breeding: Before breeding, ewes should be conditioned and restored to good body condition to store nutrients for breeding and pregnancy. In ration formulation, the basis is maintaining normal metabolism. For ewes that are relatively thin and weak after weaning, nutrition should also be appropriately increased to restore body condition.
The Boer ewes raised by the Lishui County breeding sheep farm are also mainly barn-fed. Dry roughage such as sweet potato vines and peanut vines is provided for free feeding. They are grazed for about 4 hours per day. During this period, each ewe is additionally supplement-fed about 0.4 kg of mixed concentrate per day.
(2) Feeding management during pregnancy: In the first 3 months of pregnancy, because fetal development is relatively slow, nutritional requirements are basically the same as in the non-pregnant period. In the last 2 months of pregnancy, because fetal development is very rapid, with 80% of fetal body weight growing within these two months, there should be sufficient, complete-value nutrition during these two months. The metabolic level should be increased by 15% to 20%, calcium and phosphorus content should be increased by 40% to 50%, and there should be sufficient vitamin A and vitamin D. The Boer sheep raised in Lishui are basically the same as in the non-pregnant period in early pregnancy. In late pregnancy, each sheep is supplement-fed 0.6 to 0.8 kg of mixed concentrate per day, and 3 to 5 g of bone meal per day. About 10 days before lambing, more succulent feed should also be fed.
Pregnant ewes should be managed more intensively. Prevent crowding, prevent jumping over ditches, prevent startling the flock, and prevent slipping. Daily activities should mainly be "slow and steady." They must not eat moldy feed or frozen feed, to prevent miscarriage.
(3) Feeding management during lactation: The 2 to 3 months after lambing are the lactation period. In the 2 months after lambing, breast milk is an important nutrient for lambs, especially within 15 to 20 days after birth, when it is almost the only nutrient, so complete-value feeding of ewes should be ensured. Boer lamb daily gain during the lactation period is generally 200 to 250 g. For every 100 g of gain, about 500 g of breast milk is needed, and to produce 500 g of milk, 0.3 kg of air-dried feed is needed, namely 33 g of protein, 1.8 g of calcium, and 1.2 g of phosphorus. By the late lactation period, because lambs eat more feed, supplementary feeding for ewes can be gradually reduced until stopped.
In the management of lactating ewes, attention should be paid to controlling the amount of concentrate. Within 1 to 3 days after lambing, ewes must not be fed too much concentrate, and must not be fed cold or icy water. Before lambs are weaned, the feeding amount of succulent feed and concentrate should be gradually reduced to prevent breast disease. The ewe shed should be cleaned and disinfected frequently, and afterbirth and hairballs and other filth should be removed in time to prevent lambs from swallowing them and becoming ill.
The Boer sheep raised by the Lishui breeding sheep farm, during the lactation period, in addition to free feeding of green hay, are supplement-fed 1 to 2 kg of succulent feed and 0.6 to 1 kg of mixed concentrate per day. To speed up reproduction of Boer ewes, when lambs are 15 to 20 days old, they begin supplementary feeding with commercial complete-value suckling pig feed, and are gradually fed some green feed. Generally, lambs are weaned at about 2 months of age.
3. Care and Rearing of Lambs
The rearing of lambs not only affects their growth and development but also affects their lifelong growth and production performance. Strengthening rearing plays an important role in improving lamb survival rate and improving flock quality. Therefore, great importance must be attached to lamb rearing.
Colostrum period: Milk from ewes within 5 days after lambing is called colostrum, and it is the only complete-value natural food for lambs after birth. Colostrum is rich in nutrients such as protein (17% to 23%) and fat (9% to 16%) as well as antibodies, and has nutritional, disease-resistant, and mildly laxative effects. Getting colostrum in time after birth is very important for strengthening the body, resisting disease, and passing meconium. Therefore, newborn lambs should eat colostrum as early as possible and as much as possible. The earlier they eat and the more they eat, the faster they gain weight, the stronger their constitution, the fewer diseases they develop, and the higher the survival rate.
Normal milk period (6 to 60 days): At this stage, milk is the main food of lambs, supplemented with a small amount of forage. From birth to 45 days of age is the period when lamb body length grows fastest; from birth to 75 days of age is the period when lamb body weight grows fastest. At this time, although the ewe's milk yield is also high and the nutrition is also very good, lambs should begin eating early, and be trained to eat forage, to promote fore-stomach development and increase sources of nutrition. Generally, from 10 days of age onward, grass is provided. Young tender green hay is tied into bundles and hung in the air for the lambs to eat freely. From 20 days after birth, training to eat feed begins. Semi-moist feed scalded with boiling water is placed in the feed trough to guide the lambs to nibble. After repeated times, the lambs will eat it. Note that the temperature of the scalded feed must not be too high; it should be the same as milk temperature to avoid scalding the lambs' mouths.
Milk-grass transition period (two months of age to weaning): Lambs after two months of age gradually rely mainly on eating, with suckling as a supplement. After lambs can eat feed, feed diversity is required, and attention should be paid to individual development, with adjustments at any time to promote normal development of lambs. In the daily ration, digestible protein is best at 16% to 30%, and digestible total nutrients at 74% are suitable. At this time, lambs should also be given appropriate exercise. As age in days increases, drive the lambs to pasture for grazing. Grazing mothers and lambs separately is beneficial for weight gain, condition building, and prevention of parasitic diseases. Lambs to be weaned must all be dewormed before transfer to another group or sale.
4. Feeding Management of Replacement Sheep
Sheep from weaning to before breeding are called young sheep or replacement sheep. This stage is the period when the sheep's bones and organs fully develop. If nutrition cannot keep up, it will affect growth and development, constitution, feed intake, and future reproductive ability. Strengthening rearing can increase body size, promote organ development, and play an important role in improving future meat production ability and enhancing reproductive performance.
Abundant nutrition and sufficient exercise can make young sheep broad-chested, with well-developed heart and lungs and a strong constitution. Semi-grazing and semi-barn feeding is the most ideal feeding method for raising young sheep. From weaning to 8 months of age, on the basis of eating enough high-quality hay each day, supplement-feed 250 to 300 g of concentrate containing 15% digestible crude protein. If grass quality is excellent, less concentrate may be given. Because young rams grow faster than young ewes, they should be given more concentrate. Exercise is even more important for young rams, not only benefiting growth and development but also preventing the formation of hay belly and bad habits.
Regular weighing is a sign of the degree of developmental perfection of replacement sheep, and this indicator must be noted in feeding. Young sheep should have their body weight sampled and measured monthly on a fixed basis, so as to check the development of the whole flock. Weighing should be carried out in the morning before feeding or going out to graze.
5. Feeding Management of Crossbred Sheep
The crossbreeding utilization of Boer goats has already been promoted on a large scale in Shandong Province, but overall the number of crossbred sheep is still not very large. Because purebred Boer goats are currently in short supply and expensive, many good crossbred rams containing Boer blood are also retained for breeding, and crossbred ewes are used for grading-up crossbreeding to produce high-blood sheep. For the feeding management of crossbred sheep and high-blood sheep used for breeding, reference may be made to the feeding management of purebred Boer goats. However, with the comprehensive development of Boer goat crossbreeding utilization, the number of crossbred sheep will increase more and more, and in the future they may become the main commercial meat sheep. Therefore, the feeding management of crossbred sheep should be studied. In the feeding management of crossbred sheep, the following points should be noted.
(1) Feed nutrition should be appropriately increased: Because crossbred sheep grow and develop relatively quickly, especially from 6 to 9 months after birth, body weight can double compared with local sheep. Their nutritional requirements are also relatively greater, and appropriate supplementary feeding should be carried out on the basis of the local sheep ration. The amount of supplementary feeding is generally determined according to weight gain requirements (see Table 2-1) and the resource situation of green feed in different seasons. Generally, for crossbred sheep born in spring, in places with good forage resources, apart from appropriate supplementary feeding before and after weaning and before marketing for fattening, no supplementary feeding may be needed at other times. However, crossbred sheep born in autumn and winter generally all need supplementary feeding; otherwise, early growth and development will be affected, and the crossbreeding effect will not be obvious. Generally, mixed concentrate is supplement-fed at 0.5% to 1% of crossbred sheep body weight.
(2) Management should be strengthened: In addition to doing general daily management well, castration should be done in time and deworming should be done regularly. Castrated sheep are gentle in temperament, easy to manage, easy to fatten, and can reduce mutton odor and improve mutton quality. Lamb castration is generally done at about 2 months after birth. Deworming of crossbred sheep is very important. Generally, flukes and nematodes are dewormed once each in spring and autumn, tapeworms are dewormed once every two months, and external parasites are dewormed once each in spring, autumn, and winter.
(3) Short-term fattening: To improve growth speed and mutton quality, crossbred sheep can undergo short-term fattening one month before marketing. According to the experience of the people of Lishui County in raising crossbred sheep, under normal grazing conditions, crossbred sheep about 6 months old are supplement-fed 150 g of corn, 100 g of bran, 50 g of soybean meal, and 3 g of bone meal per day. After about one month of fattening, they can gain 6 to 8 kg.
(4) Lambs marketed in the same year: Promoting the marketing of lambs in the same year is of great significance for reducing forage requirements in winter and spring, avoiding "thin in winter, dead in spring," and increasing the commodity rate. The crossbreeding utilization of Boer goats provides more favorable conditions for marketing lambs in the same year. Crossbred sheep grow especially fast in the early stage; generally at 6 to 9 months of age, body weight can reach 25 to 30 kg. Even for crossbred sheep born in autumn, as long as nutrition is strengthened and supplementary feeding is reasonable, they can grow to about 20 kg at about 4 months of age. In addition, reasonably arranging breeding time is also a measure to ensure that lambs are marketed in the same year.
(5) Use of additives: There are many types of additives, whose main functions are to supplement nutrients, promote growth, prevent disease, and provide health care, etc. Additives commonly used for goats include mineral additives, rare earth feed additives, and deworming and health-care additives, etc. According to reports, adding 0.02% rare earth to the daily ration of fattening sheep after weaning increased average daily gain by 17.1% and feed conversion rate by 14.29% during a 60-day trial period. Monensin can promote propionic acid fermentation by changing the metabolic process and microbial activity in the rumen, thereby promoting weight gain and improving feed conversion rate. Monensin is mixed into feed in the form of a feed additive and fed. Generally, 25 to 30 mg is added per kg of daily ration, but care must be taken to mix it thoroughly and evenly. Zeranol is made from zearalenone by hydrogenation and reduction (the commercial product includes "Xudazhuang"). It does not belong to the hormone category, but it can prompt the sheep's pituitary gland to release growth hormone and promote protein synthesis. Therefore, it can not only promote the growth of muscle and fur but also promote bone development.