(1) The relationship between reproduction and lactation When the weight of ewes ewes reaches 70%-75% of the weight of adult ewes, or the weight of purebred sag ewes reaches 42-45 kg, and that of hybrid sheep is 32-35 kg, Can breed. After ewes are born, there are 10 months of milk production, 2 months of dry milk, year after year, until life, this arrangement, the final production of milk up to. According to the parity, the third child's milk yield can reach the highest peak. Most ewes give birth in February of each year and naturally estrus in September. The milk can be mated again in 7 months. In the first 3 months of pregnancy (September to October), both lactation and conceiving, but at this time the ewe's lactating function declines, the fetus gains slowly, and the nutrients needed for lactation have little effect, so it will not affect Lack of milk supply, lactation, and pregnancy do not produce contradictions in nutrient supply. (2) Lactation curve The lactation curve is a statistical index graph of the milk production of dairy goats in the lactation period. The distribution curve of milk production of milk goats each month is connected. It is used to assess the smoothness of dairy goat milk production during lactation as a basis for scientific feeding. Generally 20 days after the ewes lamb, due to the strong effect of prolactin, coupled with the nutritional reserve dry milk, milk production rose rapidly, to 40-70 days after delivery, reaching the highest peak. After 200 days, the milk production decreased slowly. After 180 days, especially after 210 days, the rate of decline was rapid, and lactation stopped until dry milk was reached within 300 days. After puerperal delivery, the ewes begin to lactate at the peak of milk production in one pass and then descend into the dry period to stop lactation and form a parabolic lactation curve. The lactation curve of milk production of high-yield dairy goats has a high starting point, and the rising and falling margins are relatively small. The peak lactation curve is flat, long lasting, and slows down. The lactation peaks of low-yielding dairy goats appear early and rise quickly. However, the lactation curve has a low peak, short duration, and rapid decline. (3) Change in milk fat rate The rise and fall of milk fat rate is the opposite of the lactation curve. After the delivery of colostrum, the highest milk fat rate can reach 8%-10%. As the milk production rises, the milk fat percentage decreases, and when milk yield is highest, the milk fat percentage is the lowest. With the decrease of milk production, the milk fat percentage gradually increases. The change in milk fat percentage is not as significant as the amount of milk produced. It is only slightly higher at the beginning and end of lactation, and it does not change much in the middle long term. Although the milk fat rate is the opposite of the milk yield, the daily milk fat production distribution curve is consistent with the amount of milk produced, and the most milk fat is produced at the peak of lactation. (4) Changes in body weight In a lactation period, the weight of ewes changes according to the following rules: the weight of the ewes is the largest, and after delivery, the fetus, the birth-restraint, etc. are discharged, and the body weight is obviously decreased. The colostrum period is slightly restored. After that, the amount of ewes is related to the amount of lactation. With the increase, the body weight continues to decline until the peak of lactation, and the body weight is reduced to the lowest. Until half of the lactation period, which is the sixth month of the lactation period, as the amount of milk produced gradually decreases, the weight begins to increase. After 7 months of lactation, weight gain was accelerated and weight gain after dry milk was faster. The increase in body weight of ewe during dry-milk period should include two aspects: first, the growth and development of the fetus; second, the increase in the degree of ejaculation in the ewe. Therefore, it is necessary to strengthen the feeding during the dry period so as to ensure the healthy development of the fetus on the one hand, and on the other hand, the ewes can restore their strength as soon as possible so that sufficient nutrients can be stored in the body to ensure the production of the next lactation period. (5) Feeding principle The general feeding principle is to hope that dairy goats can safely feed in large quantities, meet the needs of lactation as soon as possible, and consume as little as possible in the body to create conditions for high and stable production. In the stage of colostrum after a few days of birth, due to the accumulation of nutrients in the ewes and the lack of lactation, the amount of feeding should be small. Later, with the increase of the amount of lactation, the amount of feeding should be gradually increased and the amount of lactation decreased. The amount should also be reduced accordingly. The feed repayment of goat milk is related to milk production. When the milk yield is high, the feed utilization rate is high. If the milk production is 3.5 kg/day, the total digestible nutrients will be 1.5 kg; if the milk production is the lowest, the feed utilization rate will be low, and if the milk output is 1 kg per day, 0.91 kg will still need to be given. The total digestible nutrients. For this reason, we should make full use of the high feed compensation period in production. In the stage of rising milk production, when increasing the amount of feed, it is necessary to increase the amount, that is, when the feed is basically adapted to the milk production, it will continue to increase, so that the diet needs more nutrition than the actual milk production. After the material is added and the amount of milk no longer rises, the excess feed is reduced. When milk production declines, the drop will be slower than feeding, gradually adapting to the output, that is, reducing the material, the output will fall rapidly. It is obvious that the amount of feed at this time is not necessarily the same as the feed standard. After lambs are raised in the lactation period, they enter the lactation period, and during the lactation period, they can secrete the early stage of lactation, the prolific period of lactation, and the late stage of lactation. During different lactation periods, the ewes' physiological conditions and productivity are also different. There are also differences in the requirements for nutrient substances. They must be bred according to the nutritional requirements of different physiological stages so that sheep can obtain full-price balanced diets without causing waste. (6) The early stage of lactation is the initial period of lactation within 15 days after delivery. After delivery, the ewes consume a lot of energy, their physique is weak, their stomachs are empty and their digestive function is poor; genital organs have not recovered, and the functions of the mammary glands and blood circulation system are not normal, and multiple fetuses are overburdened by the heart during pregnancy and the abdomen and breasts The edema at the base has not yet disappeared, and at this time the recovery of ewes should be the main force. The specific feeding principle is based on high quality tender hay, and then see the ewes body fat, skin swell, appetite performance, fecal shape and odor, flexible feed and juicy feed. Normally 15 days after childbirth, 0.1-1.3 grams of bran can be fed daily and 0.5 kg of silage; 7-10 days after delivery, 0.2-0.3 kg of mixed concentrate can be fed daily, and 0.5 kg of silage can be used daily for 10-15 days. 0.3-0.5 kg of mixed concentrate can be fed and 0.7 kg of silage. After 15 days of lamb production, it gradually returns to normal feeding standards. During the early lactation period, care should be taken to ensure that, first of all, sufficient high-quality hay is allowed to freely feed, but the amount of concentrate and succulent feed must be increased from small to large, and the amount of feed must be increased slowly. Do not rush too fast, otherwise it will affect the ewe. Recovery of physique and recovery of reproductive organs are also prone to gastrointestinal diseases such as indigestion. Light affects the amount of milk produced in the sub-primary fetus, while it harms life-long production performance. For people with good lyricism, over-large breasts and indigestion, they should be fed with high-quality green hay. They should not feed green and juicy feed, control drinking water, and give less concentrate, so as not to increase digestive disorders and breast swelling, delaying the absorption of edema. For those who are leaner in body condition, weak in digestive ability, lack of appetite and breast swelling, they may feed some potato feeds with high starch content in appropriate quantities, and carry out extra-hospital exercise to enhance physical strength. (7) The procreative period of lactation is 15-180 days postpartum. High-yielding dairy goats reach the peak of lactation 60-70 days after childbirth. Generally, dairy goats reach the peak of lactation 30-45 days after childbirth, and then maintain a relatively stable high-yield period, and milk production begins to decrease after 180 days. The period of lactation is the highest period of milk production. Various nutrients stored in the body are continuously paid and weight is continuously reduced. During this period, dairy goats have a strong appetite and high feed utilization rate. They should use the best feed conditions to provide the best rations and promote their prolific milk production. In addition to feeding 2% to 4% of high quality hay each day, try to feed more silage, grass, and root tuber juice as much as possible. Insufficient nutrients are supplemented with mixed concentrates. In order to stimulate the full play of lactating function, some feeds can be fed in excess of the standard. If overfeeding feeds increase milk production, they should continue to be fed and the original dietary standards should be adjusted. If it is not possible to increase the amount of milk, extra portions should be removed. . In the high lactation period, high-yielding dairy goats eat more than 10 kg of feed per day. To make it safe to consume such a large amount of feed, attention must be paid to the volume and palatability of the diet. The volume of the diet should be small, and the palatability should be better. , high nutrition, variety, easy to digest. And from all aspects to improve the digestion of dairy goats, such as proper exercise, increase the number of feeding, improve feeding methods, regular quantitative, less to Tim Tim, clean. In the stable period of milk supply, changes in feed, feeding methods, and work schedules should be avoided as much as possible, and all possible means of keeping the peak of lactation more stable for a longer period of time. If the milk yield at the peak of lactation declines, it is very difficult to go up. (8) Late lactation 180 days after lactation enters the late lactation phase. Due to the gradual cooling of climate and the deterioration of forage conditions, together with the effects of estrus and pregnancy, the milk production is significantly reduced. At this time, it is necessary to maintain the nutritional status of sheep and gradually reduce the amount of concentrate feed, but it cannot be reduced too quickly. With the decline in milk production gradually decreased. If the refined material is reduced too quickly, the amount of milk produced can be drastically reduced, affecting the total output of the fetus. Conversely, if the diet for a longer period of time exceeds the nutrients required for lactation, the ewes will soon become fattened, which can also reduce the milk production. In short, at this stage it is necessary to increase the weight of the ewes not only too quickly, but also to make the decline in milk production more slowly. In this way, in addition to gradually reducing the fine material every day, should try to supply high-quality green hay and juicy green feed, to extend the lactation period, increase the sub-primary milk production, is conducive to the healthy development of the fetus, but also for the next fetus The lactation accumulates physical strength. China Agricultural Network Editor