Key Technical Points for the Breeding and Management of Small-tailed Han Sheep

1. Feeding and Management of Growing Sheep

Growing sheep refers to sheep from weaning to before their first mating (ewes at 3—8 months of age; rams at one year old). The quality of feeding at this stage directly affects the sheep's physical development, production performance level, and quality. Therefore, the following aspects of work should be done well:

(1) Strengthen nutrition to promote physical maturity

The feeding of growing sheep shifts from being based mainly on milk and concentrate to being based mainly on roughage. At this time, the sheep's plasticity is extremely strong; improper feeding and management can cause stunted growth and development, affecting the sheep's overall production performance. Sufficient high-quality green hay or green fodder should be supplied regularly, along with a certain amount of concentrate supplement, so that the sheep receive adequate nutrition and their growth and development speed is accelerated.

(2) Separate males and females into groups, and mate at the appropriate time

Small-tailed Han sheep can reach sexual maturity at 5—6 months of age. If they are allowed to mate whenever they come into estrus, premature pregnancy will inevitably affect the ewe's growth and development. Therefore, males and females should be separated into groups, and the age for a ewe's first mating should be limited to 8 months, or preferably when body weight reaches 40 kg.

(3) Castrate at the appropriate time

For some male lambs that cannot be used for breeding, castrate them at the appropriate time and sell them after short-term fattening.

2. Feeding and Management of Ewes

The feeding and management of ewes greatly affects the development, growth, and survival of lambs. The gestation period of Small-tailed Han sheep is 5 months, and the lactation period is 3 months; during the lactation period, they can come into estrus and mate. After mating and conception, in order for the embryo to fully develop and for the ewe to have sufficient milk after giving birth, there must be an adequate nutrient supply as the foundation. Therefore, the feeding and management of ewes must be done well consistently throughout the year.

Small-tailed Han sheep have the reproductive characteristic of “two births per year and multiple lambs per birth,” so their production continuity is quite close. Feeding should also target this characteristic by feeding according to the nutritional needs of the sheep at each physiological stage. Two feeding and management methods are introduced below.

(1) Staged feeding method

The staged feeding method means adopting corresponding nutrient supply according to the nutritional needs of sheep at different physiological stages, divided into the gestation period and the lactation period.

1. Feeding and management of pregnant ewes

The period from mating and conception to lambing is the gestation period. The task of feeding and management during gestation is to protect the pregnancy and ensure good fetal development. The gestation period is further divided into early gestation and late gestation. In early gestation, because fetal development is slow, nutritional needs do not increase noticeably, and under normal circumstances the nutritional needs of the fetus can be met. In late gestation, because fetal growth and development accelerate, 90% of the lamb's birth weight is gained during this period. If nutrition is inadequate at this stage, it will cause low lamb birth weight, low survival rate, weak resistance, and susceptibility to death. Moreover, nutrient deficiency at this time will lead to a lack of milk in the ewe after delivery. Therefore, at this stage, in addition to normal growth, it is best to supplement 0.25—0.5 kg of mixed concentrate.

The gestation period of Small-tailed Han sheep is 150 days. If feeding and management are improper during gestation, it can easily cause miscarriage and premature birth. It is strictly forbidden to feed moldy, spoiled, frozen, or other abnormal feed, and it is forbidden to drink ice-cold water on an empty stomach. In daily management, frightening, running rapidly, jumping over ditches, and other strenuous actions are prohibited; especially when entering or leaving the pen gate or during supplementary feeding, mutual squeezing must be prevented. Ewes in late pregnancy should not receive epidemic prevention injections. From 7—10 days before lambing, preparations for lambing and rearing should be made well. From 5 days before lambing, attention should be paid to duty observation in order to assist with lambing. Ewes about to lamb should be kept separately in a clean and hygienic birthing room spread with clean bedding straw. When the ewe shows signs of labor, someone should stay with her and let her give birth naturally; in case of dystocia, a professional veterinarian must handle it on site.

2. Feeding and management of lactating ewes

The stage from the lamb's birth to weaning is the lactation stage. Small-tailed Han sheep generally have a lactation period of 3 months. The main task at this stage is to ensure the ewe has sufficient milk for nursing, especially within one month after birth, which is even more important. At this time, the lamb's growth and development mainly depend on breast milk. If the ewe's nutrition is poor, milk yield will decrease, not only affecting the lamb's growth and development but also causing the ewe's own body weight to decline. To improve the ewe's lactation ability, more fresh grass, hay, and succulent feed should be fed, and an appropriate amount of concentrate supplement should be added, while paying attention to the supply of minerals and trace elements. In late lactation, the ewe's lactation strength declines, and since the lamb has already eaten crushed mixed concentrate, it mainly no longer depends on breast milk for survival. In addition to normal feeding, the supplementary feeding can be appropriately reduced.

During lactation, the pen should be kept clean and hygienic at all times, and afterbirth, hair balls, stones, and moldy grass should be cleaned up promptly to prevent lambs from licking them and causing disease.

The ewe's udder should be checked frequently. If teat blockage, udder inflammation, suppuration, or excessive milk is found, corresponding measures should be taken promptly to deal with it.

When weaning lambs, the supplementary feeding of succulent feed, silage, and concentrate for the ewe should be reduced a few days in advance to prevent mastitis.

(3) Balanced feeding method

This feeding method is based on the sheep's approximate nutritional requirements, without dividing stages or before-and-after periods. In addition to normal roughage feeding, a certain amount of concentrate is supplemented. This method is simple and easy to carry out, but it is not as scientific and reasonable as the former.

3. Feeding and Management of Breeding Rams

The quality of breeding ram feeding plays a decisive role in sheep production. As the saying goes, “A good ewe benefits a litter; a good ram benefits a flock.” That is the reasoning. Small-tailed Han sheep are mostly raised in scattered households, so not every household needs to keep a ram; generally, 1 ram for every 30—40 ewes is more suitable. Breeding rams must be raised separately and should maintain a balanced nutritional state throughout the year, neither fat nor thin, and full of energy. Although Small-tailed Han sheep ewes come into estrus year-round, mating is not concentrated, so the ram's mating task is not heavy. However, there is still a distinction between peak and off seasons for mating. Therefore, the feeding and management of breeding rams can be divided into two stages: peak mating season and off mating season. Generally, spring and autumn are the peak seasons, while winter and summer are the off seasons. Doing a good job in feeding and management during the peak mating season is very important.