Mixed breeding of rams and ewes has many disadvantages.

First, it is not conducive to grasp the best mating time.

When rams are mixed with ewes, they are bound to mate freely, which may lead to ewes getting pregnant and giving birth to lambs all the year round. This is not conducive to feeding and management, but also not conducive to fetal development, the birth of lambs are often poor physique, low survival rate. Comparatively speaking, ewes give birth to lambs better in spring and winter, and lambing in winter is better than that in spring. The ewes who give birth to lambs in winter are usually pregnant from July to August, when the grass is lush, the ewes are in good health, ovulate more, the conception rate is high, and the fetus develops well; when the lambs are weaned, the weather is getting warmer and can eat green grass. rapid growth and development, strong overwintering ability, high survival rate and high wool yield. Therefore, it is best to keep the ram and ewe separately and choose the ram to mate with the ewe from July to August, so as to ensure that the ewe will produce lambs from December to January of the following year. If the ewe gives birth to lambs in spring, both the ewe and the lamb can eat grass, so the ewe has plenty of milk, the lamb grows fast, does not need to buy a large amount of feed, and the cost is low.

Second, it is not conducive to grasp the best breeding object.

Generally speaking, sheep are sexually mature at the age of 7 ~ 8 months, but it is not suitable for breeding at this time; in addition, old sheep and sick and disabled sheep are not suitable for breeding, only healthy sheep aged 1.5 to 7.0 years old are suitable for breeding. If the rams and ewes are mixed together and mate freely, the old, weak, sick and young will become pregnant, which not only affects the treatment of the old, weak, sick and dead ewes, but also the survival rate of lambs is low and the growth is slow.

Third, it is not conducive to the utilization of well-bred rams.

Generally speaking, a ram can only mate with 15 to 20 ewes. If the ram and ewe are allowed to mate freely, it will consume too much energy of the ram, shorten the useful life, and cause waste.

Fourth, it is not conducive to giving full play to hybrid advantages.

Free mating is often not sure which ram the father of the lamb is, resulting in inbreeding, loss of heterosis and genetic diseases.

5. It is not good for ewes to feed.

When the ram is mixed with the ewe, the ram will often chase the ewe, and the ewe can not concentrate on feeding, thus affecting the growth and development of the ewe.