Because it is not easy to choose sows, and not all female pigs can be used as sows. Sows must have strong fertility and vigorous vitality. These things are not obvious at a glance and need to be screened. There are some skills in the selection of sows: sows aged 8~ 10 months and weighing more than 180 kg can be considered as reserve sows. After the primary election, the selection of reserve sows should be divided into three stages (three stages) based on the principle of "gaining about 400 grams per day":
(1) The first stage lasts for 37 days and weighs 40-70kg.
(2) The second stage lasted 63 days and the weight reached 70~ 120 kg.
(3) the third stage, 75 days, weight 120~ 180 kg.
If the growth rate of the selected sow reaches the third stage standard, it can indeed be used as a sow.
Second, the four main points of sow reproduction
Because the sow determines the production efficiency, so the four key points of sow breeding need to be firmly remembered by pig farmers:
(1) Spare sows cannot eat piglet feed.
Many pig farmers will choose to buy back sows, and the weight of sows may be relatively light (sometimes 120, 130 kg), so they will consider feeding ordinary fertilizers. But this is not right. The nutrition, calories and protein required by sows are higher than those of fattening pigs. Adequate nutrition plays a decisive role in the secretion of estrogen by sows, which indirectly determines the production efficiency of sows. Therefore, the feed of the sow is different from that of the piglet.
(sow should be managed in columns.
Spare sows cannot be raised with fattening pigs and must be fenced. Because the feed is different, it is impossible to manage sows more efficiently and scientifically if they are mixed together. Moreover, it is convenient to patrol the fence regularly and record the condition of the reserve sow that day. At this time, even if there is pig farm management software, it is useless to divide the fence.
(3) sow should be set before it is too late.
The character of the reserve sow must be docile, so it is convenient for breeding and childbirth, so the domestication and training of the reserve sow should start from an early age. From the piglet stage, it is necessary to carry out password training, so that sows can learn some basic movements, touch sows and make them closer to people. The gilts at this stage can be fed as pets.
(4) Do a good job in environmental management.
The estrus of gilts has a lot to do with the environment. After formal development and maturity, besides contact with boars, environmental factors are the biggest factors of estrus. Therefore, it is very important that the environment is clean and safe, and ventilation and lighting need to be just right. If the environment is not good, the smell is too strong and the ventilation is not good, it will not only breed bacteria, but also lead to the situation that sows are not in estrus, so environmental management should be done well.