There are three main types of sows, powder, liquid feed and granule.
Powder can be divided into the user's own mix of coarse powder (simple mixture) and commercial fine powder. Liquid feed is a form of feed developed in European countries in the last decade to reduce antibiotic use and improve the welfare of sows. With the sharp rise of corn price in recent years, some customers realize that the demand for matching grain increases sharply when the cost of mixing and matching grain is almost the same. Therefore, feed mills are developed to cope with market changes. But the use of granule material, there has been controversy, now combined with sow nutrition physiology and production practice problems, to analyze, welcome fellow pai Brick (this paper only represents the author's personal views).
1、The feed intake of sows on powder was greater than that on grain
The main reason behind this fact is that sows have large teeth, flexible tongues and large mouths, and the stimulation of powder to taste and smell causes the secretion of digestive juices in the first period compared with the amount of grain. Salivary amylase also acted more rapidly on powders than granules.
So sows have a stronger appetite for powder. In the wild, sows have a wide range of food, including root tubers, green feed, grain seeds, small animals, and so on. Mature grain seeds are very hard, so grain food is not the first choice for sows. In addition, pigs have the habit of scrambling for food, and the consequences of eating a large amount of granule at one time are very serious: the unchewed granule remains in the digestive tract for a long time, and the insufficient secretion of digestive fluid in the first stage also leads to the slow down of digestive tract peristalsis. Especially in the perinatal period, sows decreased appetite and constipation appeared inevitable.
2、Powders are "fresher" than grains
As is known to all, powder is not easy to be kept. In the north, the storage time in summer cannot exceed 15 days, because it has a larger area of contact with oxygen in the air after being opened and is easier to be oxidized. Particles, on the other hand, have a smaller contact area with the air after being squeezed, so they can be kept for a longer time. In terms of field application results, powder produced within 3 days is more advantageous (less intermediate links, better for sows).
After quenching and tempering, pressing, cooling, grading, packaging and other processes produced, is it not a sow the best feed? There is no economic factor involved here, just the following points:
(1)Can the cooling fan cool the newly produced materials quickly in summer?
(2)Is the granulation process effective for sterilization? From the aspect of microorganism, dry heat sterilization is better than wet heat sterilization, but can the granulation process be achieved? Besides, the granulated material is always transported to the finished product warehouse in a semi-open way. Is there any possibility of secondary contamination?
(3)Some heat sensitive material is like phytase, microzoology preparation and vitamin to wait, safe threshold quantity raises a level how many is advisable? As far as common sense goes, as long as the enzyme protein has no more than a 10% chance of surviving at high temperatures, what does that mean?
3、Powder material is more adaptable than particle material
For fattening pigs, the finer the powder is, the higher the digestibility, and the 2.0-3.0mm particles are most welcome on the premise that they are free from digestive tract ulcers. On the other hand, sows, especially those within 3 foetuses, should be given full play to their genetic advantage of high litter rate since their feed ensures a certain lean meat growth rate and exercises their gastrointestinal function.
On the premise that the nutrient demand is satisfied, the pulverized grain size of the feed is closely related to the function of the upper digestive tract, and the fiber content of the feed is related to the fermentation of the posterior intestine. Most studies have shown that the pulverized grain size of about 4.0mm is more beneficial to the health of sows, while the crude fiber content of 5%-8% is beneficial to the improvement of the moderate growth of microorganisms in the hind intestinal segment of sows. These two indexes are very unfavorable to the production of granule, and the most critical point is that they have a great impact on the service life of the ring mold.
So what would be the ideal sow feed? In order to maintain sows' performance, I think sows' feed should consist of three parts:
First, it is the powder material with full nutritional value. In order to ensure the digestibility of nutrients such as protein, the crude fiber level should not exceed 5%. The feeding method can be wet mixed material (water to material ratio 2-3:1) or wet feeding (water to material ratio within 1:1).
Two is the green feed or root tuber kind of feed, can be washed after chopping feed, supplement partial fiber and vitamin, at the same time can play the role of gastrointestinal health care.
The third is the soil or peat feed, the role is to protect the sow hoof quality health. The main reasons for the high frequency of population renewal, poor bone development and weak hoof quality of modern sows bred with high intensity are that they are often eliminated due to joint problems or hoof quality problems before reaching 5 or 6 yield.
