CN116686916A - Sow feed capable of reducing invalid piglet rate and promoting red hair and brightness of newborn piglet skin - Google Patents

Abstract

The invention discloses a sow feed capable of reducing the rate of ineffective piglets and promoting the red hair of newborn pigskin to be bright, and belongs to the technical field of livestock and poultry cultivation. The sow feed comprises the following components: 99.73-100% of basic ration, 0-0.27% of protein iron, and the protein iron is not 0. The basic ration comprises the following components: corn, wheat bran, soybean hulls, soybean meal, salt, stone dust, calcium bicarbonate, soybean oil, choline, baking soda, lysine, threonine, tryptophan, valine, glucose, fish meal, a mildew preventive, an antioxidant, phytase, fermented soybean meal and premix. The sow feed is fed in the late gestation period and lactation period of sows in a specific feeding mode, so that the iron nutrition level and the transmission efficiency of sows and piglets can be obviously improved, the invalid piglet rate is obviously reduced, the red hair and the bright of the pigskin of the newborn piglets are promoted, the feed intake of the sows and the average daily gain of the piglets in the lactation period are improved, and the reproductive performance and the growth performance of the piglets of the sows are improved.

Description

Sow feed capable of reducing invalid piglet rate and promoting red hair and brightness of newborn piglet skin

Technical Field

The invention relates to the technical field of livestock and poultry breeding, in particular to a sow feed capable of reducing the rate of ineffective piglets and promoting the red hair and the brightness of pigskin of newborn piglets.

Background

The efficient sow feeding is a source for ensuring stable production of live pigs, and the genetic characteristics of modern sows are greatly changed along with the change of breeding and feeding management, so that the method is mainly characterized in that the number of piglets produced in litter is increased, the birth weight of the piglets is reduced, the variation coefficient between litter is large, the feed intake in lactation period is reduced, and the like.

Iron deficiency anemia (Iron deficiency anemia, IDA) caused by iron deficiency is a common nutritional disorder that severely affects animal health and growth and reproduction, and is frequent in the late gestation and lactation of sows. Iron deficiency in gestation can reduce reproductive performance of sows, often resulting in increased labor and resulting in dystocia, and increased numbers of dead, mummy and low-birth weight piglets. The sow has the advantages that mental depression, reduced feed intake, reduced organism resistance and easy stress during iron deficiency in the lactation period of the sow, poor lactation is usually generated after the sow has IDA, and piglets can be refused by the sow during sucking milk, so that the occurrence of piglet IDA is easy to be caused, and the phenomena of slow growth speed and low piglet breeding rate are generated. The incidence rate of the IDA of the piglets is up to 30-50%, and the death rate of the piglets is up to 15-20%. Therefore, it is necessary to develop a sow feed which can prevent the occurrence of IDA in the piglets, further reduce the rate of ineffective piglets and promote the red hair and the brightness of the pigskin of the newborn piglets.

Disclosure of Invention

The invention aims to provide a sow feed capable of reducing the rate of ineffective piglets and promoting the red hair and the brightness of pigskin of a newborn piglet so as to solve the problems in the prior art.

In order to achieve the above object, the present invention provides the following solutions:

one of the technical schemes of the invention is as follows: sow feed capable of reducing invalid piglet rate and promoting red hair and brightness of newborn piglet skin comprises the following raw materials in percentage by mass: 99.73-100% of basic ration, 0-0.27% of protein iron, and the protein iron is not 0.

The sum of the mass percentages of the basic ration and the ferritin is 100%.

Further, the raw materials of the basic ration comprise the following components: corn, wheat bran, soybean hulls, soybean meal, salt, stone dust, calcium bicarbonate, soybean oil, choline, baking soda, lysine, threonine, tryptophan, valine, glucose, fish meal, a mildew preventive, an antioxidant, phytase, fermented soybean meal and premix.

Further, the sow feed for reducing the invalid piglet rate and promoting the red hair brightness of the newborn piglet skin comprises the following raw materials in percentage by mass:

further, the iron content of the protein iron is 15wt.%.

Further, the premix comprises the following components: iron, zinc, copper, manganese, iodine, selenium, cobalt, vitamin A, vitamin D3, vitamin E, vitamin K3, vitamin B1, vitamin B2, vitamin B6, vitamin B12, nicotinamide, calcium pantothenate, folic acid, biotin, L-ascorbic acid C, and 25-hydroxycholecalcia.

Further, the premix in 1kg of the basic ration comprises the following components: 5000IU of vitamin A, 3500IU of vitamin D, 15mg of vitamin E, 31.2mg of vitamin K, 11mg of vitamin B, 25mg of vitamin B, 62.5mg of vitamin B, 120.01mg of vitamin B, 10mg of nicotinamide, 4mg of calcium pantothenate, 1.12mg of folic acid, 0.24mg of biotin, 50mg of L-ascorbic acid, 17.5 mug of 25-hydroxycholecalcia, 154mg of iron, 100mg of zinc, 22mg of copper, 50mg of manganese, 0.56mg of iodine, 0.5mg of selenium and 0.56mg of cobalt; wherein the iron is derived from inorganic iron, and the selenium is derived from inorganic selenium.

The second technical scheme of the invention is as follows: the preparation method of the sow feed for reducing the invalid piglet rate and promoting the red hair brightness of the newborn piglet skin comprises the following steps: and weighing the raw materials of the components according to a proportion, and uniformly mixing to obtain the sow feed for reducing the invalid piglet rate and promoting the red hair brightness of the newborn piglet skin.

The third technical scheme of the invention: the application of the sow feed for reducing the invalid piglet rate and promoting the red hair brightness of the pigskin of the newborn piglet in improving the reproductive performance of the sow and the growth performance of the piglet.

The technical scheme of the invention is as follows: a method for feeding a sow in a period from a late gestation period to a lactation period, comprising the following steps:

(1) The daily feed feeding amount of each sow is 2.5kg after 85-90 days after mating;

(2) The daily feed feeding amount of each sow is 3.0kg 91-95 days after the breeding;

(3) 96-107 days after mating, the daily feed feeding amount of each sow is 3.5kg;

(4) 108 days after mating-delivery, wherein the daily feed feeding amount of each sow is 0-3.5kg;

(5) 1 to 6 days after delivery, the daily feed feeding amount of each sow is 1.0kg in 1 day after delivery, and 1.0kg is added in 2 to 6 days after delivery;

(6) The daily feed feeding amount of each sow is free feeding after 7-21 days after delivery;

the feed is the sow feed for reducing the ineffective piglet rate and promoting the red hair of the newborn piglet skin.

Further, the gestation period is 85 days after hybridization-delivery, the lactation period is 1 day to 21 days after delivery, the gestation period (pre-delivery period) is generally 114 to 116 days, and the period from 108 days after hybridization-delivery is regarded as one week before delivery.

Further, pregnant sows are limited to be fed in a limiting fence, the sows are fed with the feed 30 days before the pre-natal period (85 days after the mating), two meals are fed every day, namely 7:00 a morning and 15:00 a afternoon, and the feeding amount is fixed every meal (half of the feeding amount of every meal feeding day) after 85 days to 107 days after the mating; the sows are driven into a delivery room for feeding one week before delivery (108 days after mating), 7:00 and 16:30 daily feeding is carried out, and daily feed supply is properly reduced according to the feeding condition of the sows in the daily feed feeding range; feeding is limited 6 days before the lactation period of the sow, and the feeding is gradually added; feeding the sow for 7-21 days freely (feeding 1.5kg firstly, if the sow is full, the sow can lie down for rest, if the sow continues to stand and arch the feeding groove, feeding again, feeding a small amount of times, ensuring the sow to feed freely until the sow is full, the sow lies down for rest, and recording the feed intake); two meals were fed daily in the whole lactation period, 7:00 a.m. and 18:00 a.m..

Further, the sow is a growing binary multiparous sow (2-3 fetuses).

The invention discloses the following technical effects:

(1) The feed for reducing the invalid piglet rate of the sow and promoting the red hair brightness of the newborn piglet skin is added with the protein iron with the advantages of good chemical stability, high biological potency and easy digestion and absorption, so that the iron content, transferrin content, iron saturation and iron content in milk of the newborn piglet serum and umbilical cord blood, the normal milk lactoferrin content and the expression of transferrin and receptors in placenta are improved, the mother body effectively supplements iron to the piglet through blood, placenta and milk, the iron nutrition level of the newborn piglet and the transmission efficiency of mother source iron are improved, and the red hair brightness of the newborn piglet skin is promoted; in addition, mRNA expression and placenta vascular density of angiogenic factors BFGF and CD31 in NBW placenta are improved, expression of inflammatory factors HIF-alpha, TNF-alpha and IL-6 is reduced, placenta vascular function and anti-inflammatory capability are improved, and thus ineffective piglet rate is reduced, and positive effects are generated on performance of sow piglets. The sow feed provided by the invention can reduce the invalid piglet yield of the sow and promote the red hair and the brightness of the pigskin of the newborn sow under the condition of meeting the nutritional requirements of pregnant sows.

(2) Iron deficiency anemia is a high-grade disease of sows in the breeding cycle, and sows suffering from iron deficiency anemia often suffer from dystocia, stillbirth, mummy births and slow growth of newborn piglets. The occurrence of IDA of the sows and the piglets can be prevented by means of nutrition regulation and control, so that the reproductive performance of the sows and the growth performance of the piglets are improved. In recent years, the breeding industry begins to pay attention to the intervention effect of novel organic iron supplements on iron-deficiency anemia of the sow, but the regulation and control mechanism of iron supplementation of the sow on the performance of the sow is not yet elucidated. The protein iron added into the sow feed has the advantages of good chemical stability, high biological potency and easy digestion and absorption, the biological potency is higher, the utilization rate of the protein iron is 1.85 times of that of ferrous sulfate, and the protein iron is an ideal novel feed iron supplement. The invention clarifies the influence and action mechanism of different levels of iron on placenta function by researching the influence and transmission path of different levels of iron protein on the performance of sows and piglets and the hair color of piglets and focusing on placenta tissues. According to the research result of the invention, the optimal iron addition level capable of improving the performance and the transfer efficiency of the sow and the piglet can be screened, the transfer mechanism of the maternal iron is revealed, and data support and theoretical guidance are provided for improving the IDA of the sow and improving the performance of the sow and the piglet by applying the iron supplement in sow production.

(3) According to the feed feeding method for reducing the invalid piglet rate of the sow and promoting the red hair brightness of the newborn piglet skin, the sow is dynamically fed in the late gestation period and the lactation period, the nutritional energy requirements of the sow in the late gestation period and the sow in the lactation period are met, the feed is fed in a divided mode in the late gestation period and the lactation period, the feed utilization rate can be effectively improved, the invalid piglet rate of the sow is reduced, the red hair brightness of the newborn piglet skin is promoted, in addition, the average daily feed intake of the sow in the lactation period can be effectively improved due to the fact that the second meal is fed in the late lactation period of the sow in hot summer, and the average daily gain of the piglet is improved.

(4) By comparing the performance of the piglets with the placenta function of the groups added with different levels of protein iron, the invention discovers that iron deficiency or high-dose iron can cause adverse effect on the placenta function, and the invention is specifically expressed as follows: either iron deficiency or high-dose iron induces placental inflammatory responses, and high-dose iron induces oxidative stress by damaging the placental mitochondrial complex, resulting in insufficient placental angiogenesis, increasing the occurrence of dead fetus and mummy. The invention also discovers that 0.13% of protein iron (200 ppm calculated by iron element) is added into the sow feed, so that the performance of the sow and the placenta function of the sow can be improved, the iron nutrition level of the sow and the transmission efficiency of the maternal iron are improved, and the storage of the fetal pig iron is increased, thereby reducing the occurrence of invalid piglet rate of the sow and promoting the red hair and bright of the primary piglet skin.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a photograph taken of each group of newborn piglets fed with sow feed with different levels of protein iron. The left side and the right side are respectively provided with an L-photon group, an M-photon group and an H-photon group primary piglet shooting chart;

FIG. 2 is a graph showing the effect of different levels of protein iron addition to sow diets on the iron content and lactoferrin content in serum, milk and placenta; wherein, A is the serum iron content of a sow, B is the serum iron content of weaned pigs, C is the serum iron content of umbilical cord blood, D is the placenta iron content, E is the colostrum iron content, F is the normal-milk iron content, G is the colostrum lactoferrin content, and H is the normal-milk lactoferrin content; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=8;

FIG. 3 shows the effect of adding different levels of protein iron to sow diet on the serum physiological index of the sow and piglet; wherein, A is the content of ferritin in the sow delivery serum, B is the content of transferrin in the sow delivery serum, C is the sow delivery serum TIBC, D is the sow delivery serum UIBC, E is the iron saturation of the sow delivery serum, F is the content of ferritin in the piglet delivery serum, G is the content of transferrin in the piglet delivery serum, H is the piglet delivery serum TIBC, I is the piglet delivery serum UIBC, and J is the iron saturation of the piglet delivery serum; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=8;

FIG. 4 shows the effect of adding different levels of protein iron to sow feed on the biochemical index of the blood of a sow and a piglet; wherein A is the content of whole blood RBC of the farrowing sow, B is the content of whole blood HGB of the farrowing sow, C is the level of whole blood HGB of umbilical cord blood, D is the content of whole blood WBC of the sow, and E is the content of whole blood PLT of the sow; f is the content of weaned pig whole blood RBC, G is the content of weaned pig whole blood HGB, H is the content of weaned pig whole blood WBC, and I is the content of weaned pig whole blood PLT; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=8;

FIG. 5 is a graph showing the effect of different levels of protein iron added to sow diets on placental iron transfer; wherein A is mRNA expression level of iron metabolism related genes in the placenta of each group of sow, and B is expression level of iron metabolism key factors TF and TFR1 protein; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=6-8;

figure 6 shows the effect of different levels of protein iron added to sow diets on placental inflammatory factors and mitochondrial function. Wherein, A-E is the mRNA expression quantity of pro-inflammatory factors CSF3 (A), IL-1 beta (B), HIF-1 alpha (C), TNF-alpha (D) and IL-6 (E) in each group of pig placenta; F-G is the mRNA expression level of anti-inflammatory factors TGF-beta (F) and IL-10 (G) in each group of pig placenta; h is the protein expression level of mitochondrial complexes SDHA, ATPB, UQCRC, NDUFB 8; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=7-8;

FIG. 7 is a graph showing the effect of feeding different levels of protein iron in sows on placental vascular density and angiogenesis; wherein A-B is mRNA expression level of placenta angiogenesis related genes BFG (A) and CD31 (B); c is LBW and NBW placental vascular density statistics and representative field of view under 40-fold microscopy; LBW (Lowbirth weight, low weight piglets, < 1.1 kg); NBW (Normal birth weight, > 1.4kg for normal weight piglets); l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=6.

Detailed Description

Various exemplary embodiments of the invention will now be described in detail, which should not be considered as limiting the invention, but rather as more detailed descriptions of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In addition, for numerical ranges in this disclosure, it is understood that each intermediate value between the upper and lower limits of the ranges is also specifically disclosed. Every smaller range between any stated value or stated range, and any other stated value or intermediate value within the stated range, is also encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned in this specification are incorporated by reference for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the application described herein without departing from the scope or spirit of the application. Other embodiments will be apparent to those skilled in the art from consideration of the specification of the present application. The specification and examples of the present application are exemplary only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are intended to be inclusive and mean an inclusion, but not limited to.

The percentages in the examples below are by mass.

The premix in 1kg of base ration in the following examples comprises the following components:

5000IU of vitamin A, 3500IU of vitamin D, 15mg of vitamin E, 31.2mg of vitamin K, 11mg of vitamin B, 25mg of vitamin B, 62.5mg of vitamin B, 120.01mg of vitamin B, 10mg of nicotinamide, 4mg of calcium pantothenate, 1.12mg of folic acid, 0.24mg of biotin, 50mg of L-ascorbic acid, 17.5 mug of 25-hydroxycholecalcia, 154mg of iron (inorganic iron), 100mg of zinc, 22mg of copper, 50mg of manganese, 0.56mg of iodine, 0.5mg of selenium and 0.56mg of cobalt.

The iron content of the ferritin used in the examples below was 15wt.%.

Example 1

Preparing feeds with different protein iron contents:

according to the raw material compositions shown in Table 1, sow feeds with protein Iron contents of 0, 0.13% and 0.27% respectively were prepared, wherein the feed with protein Iron contents of 0 was a basic ration feed, and the feeds with protein Iron contents of 0.13% and 0.27% were equivalent to the addition of medium-dose and high-dose protein Iron respectively on the basis of the basic ration feed, and the sow feeds with the protein Iron contents of 0, 0.13% and 0.27% were named as low-level Iron group (L-Iron), medium-level Iron group (M-Iron) and high-level Iron group (H-Iron) respectively; the horizontal Iron group (M-ion) with the protein Iron content of 0.13 percent is equivalent to the addition of 200ppm of Iron element on the basis of basic ration, and the high horizontal Iron group (M-ion) with the protein Iron content of 0.27 percent is equivalent to the addition of 400ppm of Iron element on the basis of basic ration.

Table 1 sow feed composition

The preparation method of the feed comprises the following steps: weighing the raw materials of all the components according to the proportion, and uniformly mixing to obtain the sow feed.

Example 2

Influence of different levels of protein iron added into sow feed on sow reproductive performance and piglet growth performance: in order to verify the effect of the sow feed and the feeding method, the sow reproductive performance and the piglet growth performance of different levels of protein iron additive groups are compared and analyzed.

1. Test animals

The test animals are healthy 'long x big' Dans binary hybrid gilts (2-3 fetuses), and the test sites are Jiuzhou sow farm of Jiangmen Kong Cheng biological technology Co., guangdong province.

2. Test processing and grouping

On 83 days of gestation, 84 binary hybrid sows with similar gestation, pre-delivery period, fat condition and weight were selected and randomly divided into 3 groups: low-level Iron group (L-Iron), horizontal Iron group (M-Iron), high-level Iron group (H-Iron), 28 sows per group, each sow being 1 independent repeat. The three groups of sows are respectively fed with the feed of the sow in the L-ion group (with the protein Iron content of 0) and the M-ion group (with the protein Iron content of 0.13% and the Iron element content of 200 ppm) prepared in the example 1, and the feed of the sow in the H-ion group (with the protein Iron content of 0.27% and the Iron element content of 400 ppm) is fed for the period from 85 days of gestation (85 days after mating) to 21 days of weaning of the piglets in lactation. The feeding pattern is shown in tables 2 and 3:

TABLE 2 feed intake of sow during gestation period (kg/d)

TABLE 3 feed intake (kg/d) of sow during lactation period

Note that: feeding two meals each with fixed feeding amount (half of feeding amount per meal) at 7:00 a.m. and 15:00 a.m. each day 85-107 days after mating; one week before delivery (108 days after mating) sows were driven into the delivery room for feeding 7:00 and 16:30 daily. Two meals were fed daily in the whole lactation period, 7:00 a.m. and 18:00 a.m.. The feed is put in according to the feeding amount specified in the table 2 and the table 3 in gestation period and lactation period for 1-6 days, and the feed intake is recorded after the sow stops feeding; feeding 1.5kg for each meal in the lactation period of 7-21 days, if the sow is full, the sow can lie down for rest, if the sow continues to stand and arch the trough, feeding again, feeding for a small amount for many times, guaranteeing free feeding of the sow, until the sow is full, the sow lies down for rest, and recording feed intake.

3. Data analysis and processing

Data analysis was performed on 87 sows. Each sow was used as a test unit for statistical analysis. After the test data are preliminarily finished by Excel 2010 software, except dead embryo rate, weak young rate, young-building rate, invalid piglet rate, IUGR rate and fertility rate are checked by chi-square, the rest data are analyzed by single-factor variance by adopting Spass software. The normalization test of all data was performed using the Kolmogorov-Smirnov test and the variance alignment test was performed using the level's test. Duncan's method multiple comparisons were performed for those with significant differences. The results are expressed by mean value + -standard error, P.ltoreq.0.05 and the superscript of the different letters each indicate significant differences, while 0.05 < P < 0.10 indicates trending, and P > 0.10 indicates no differences between groups. The mapping was done using GraphPad Prism 8.0 software.

4. Results

The effective sample size statistics for each stage of the sow are shown in table 4. From 85 days of gestation to delivery, 4, 3 and 2 sows are eliminated from each group due to nonpregnant, disease, death and other reasons of the sows; from 0 day to 21 days of lactation, 2, 1 and 2 sows are eliminated respectively in each group due to death, poor milk, repeated hurdles and other reasons.

TABLE 4 statistical information table of the sows tested

Project	L-Iron	M-Iron	H-Iron
				Gestation 85 days (head)	28	28	28
Gestation elimination (head)	4	3	2
				Delivery (head)	24	25	26
Lactation phase elimination (head)	2	1	2
				Weaning day (head)	22	24	24

(1) Influence of different levels of protein iron added into sow feed on backfat, weight and oestrus of sow

The effect of different levels of protein iron on backfat, weight and oestrus of the sow is shown in table 5, and the results in table 5 show that the effect of different levels of protein iron on backfat weight and change of the sow (P > 0.05) and the effect of different levels of protein iron on oestrus rate and oestrus interval after weaning of the sow (P > 0.05) are not obvious.

TABLE 5 influence of different levels of iron protein added to sow feed on backfat, body weight and oestrus of sow

Note that: g85d in the table represents 85 days of gestation (85 days after mating).

(2) Influence of different levels of protein iron added into sow feed on sow reproductive performance

The influence of different levels of protein iron on the reproductive performance of the sow by the sow feed is shown in table 6, and the results in table 6 show that the addition of different levels of protein iron in the sow feed has no obvious influence on the total litter size, the number of live piglets, the number of healthy piglets, the number of weak piglets, the average weight of individual newborn piglets and the like (P is more than 0.05). The stillbirth rate (P < 0.05) and ineffective piglet rate (P < 0.05) were significantly reduced in the M-photon group compared to the L-photon group. And the mummy number produced by the sow in the M-photon group is 0, which is obviously reduced (P is less than 0.05) compared with that in the H-photon group.

TABLE 6 influence of different levels of protein iron added to sow feed on sow reproductive performance

(3) Influence of different levels of protein iron added into sow feed on feed intake in lactation period of sow

The effect of different levels of protein Iron added to the sow feed on the feed intake in the lactation period of the sow is shown in table 7, and as can be seen from table 7, the average daily feed intake (P < 0.05) of the sow in the lactation period is remarkably improved in the M-photon group compared with the L-photon group and the H-photon group.

TABLE 7 influence of different levels of iron protein added to sow feed on feed intake during lactation period of sow

(4) Influence of different levels of protein iron added into sow feed on growth performance of piglets

The influence of different levels of protein iron added to the sow feed on the growth performance of piglets is shown in table 8, and as can be seen from table 8, the influence of different levels of protein iron added to the sow feed on the average individual weight and litter weight of weaned piglets is not significant (P > 0.05). The M-photon group had a tendency to increase average daily gain in the piglets (P=0.08) compared to the L-photon group.

TABLE 8 influence of different levels of protein iron added to sow feed on the growth performance of piglets

Note that: in the scale pig raising production process, the method for raising the newborn piglets is adopted to continuously feed the newborn piglets and the number of the born piglets is regulated to improve the survival rate of the newborn piglets or the utilization rate of the sows due to the fact that the sows are not milk or are overmuch in birth after delivery, the economic values of the piglets are different or the newly born sows can be raised for more piglets. Therefore, the raising means that piglets are regulated within 48 hours after birth so as to regulate the number of the piglets after the number of the piglets in the sow is born. L21d in the table represents 21 days after delivery (day 21 of lactation).

From the test results, the addition of different levels of protein iron into the sow feed has no obvious influence on the weight, backfat and oestrus of the sow. But supplementing 0.13% of protein Iron, namely 200ppm of Iron element (M-ion group), remarkably reduces dead birth rate, invalid piglet rate and mummy number of the sow, remarkably improves average daily feed intake of the sow in lactation period, and has a tendency of improving average daily weight gain of the suckling piglets.

Example 3

Influence of different levels of protein iron added into sow feed on hair color of newborn piglets

1. Test animals

The test animals were healthy "long x large" Dans binary pregnant sows (2-3 fetuses) in example 2, and the test sites and methods (feeding amounts and feeds) were the same as in example 2. I.e. the piglets produced by the sow in example 2 were tested directly. The L-photon group, M-photon group and H-photon group were randomly selected for scoring at 9, 12 and 12 fosters, respectively.

2. Primary piglet feather color scoring method

The fur color of each piglet was scored prior to column adjustment, fur score = fur redness score + fur brightness score + fur mess score.

TABLE 9 haircolor scoring Table

3. Data statistics and analysis

After the test data are preliminarily consolidated by Excel 2010 software, single-factor analysis of variance is performed by adopting Spass software. The normalization test of all data was performed using the Kolmogorov-Smirnov test and the variance alignment test was performed using the level's test. Duncan's method multiple comparisons were performed for those with significant differences. The results are expressed by mean value + -standard error, P.ltoreq.0.05 and the superscript of the different letters each indicate significant differences, while 0.05 < P < 0.10 indicates trending, and P > 0.10 indicates no differences between groups. The mapping was done using GraphPad Prism 8.0 software.

4. Results

The pictures of the primary piglets of each group added with different levels of protein Iron in the sow feed are shown in figure 1, the hair color scoring results are shown in table 10, and as can be seen from figures 1 and 10, the hair color of the primary piglets can be improved (P is less than 0.05) by supplementing different levels of protein Iron (M-irongroup and H-irongroup) with the mother source.

TABLE 10 Primary piglet wool color score with mother source supplementation with different levels of protein iron

Example 4

Influence of different levels of protein iron added into sow feed on iron nutrition level of sow and piglet and transmission mechanism thereof

1. Test animals

The test animals were healthy "long x large" Dans binary pregnant sows (2-3 fetuses) in example 2, and the test sites and methods (feeding amounts and feeds) were the same as in example 2. I.e. the sow being farrowed, the piglet being sow produced and the sow after farrowing in example 2 were tested directly.

2. Sample collection

(1) Blood sample collection for sow and piglet

Blood sample collection of the farrowing sow: within 2 hours after delivery of the sows, randomly selecting 8 sows from each group, taking 10mL of blood from the auricular veins, sub-packaging 5mL into common blood collection tubes, standing for 30min, centrifuging for 10min at 4 ℃ and 3000r/min, collecting serum, and storing at-80 ℃; subpackaging 5mL into EDTA anticoagulation blood collection tubes, and immediately feeding samples for routine blood detection.

Collecting blood of weaned pigs: on the weaning day of piglets, randomly selecting 8 piglets in each group, taking 5mL of blood from the anterior vena cava, sub-packaging 2.5mL to a common blood taking tube, standing for 30min, centrifuging for 10min at 4 ℃ and 3000r/min, collecting serum, and storing at-80 ℃; subpackaging 2.5mL into EDTA anticoagulation blood collection tubes, and immediately feeding samples for routine blood detection.

(2) Placenta sample collection

On the day of sow delivery, randomly selecting 8 sows in each group, binding a cotton thread with a mark on the umbilical cord of a piglet after amniotic fluid is broken and the piglet is born but has not broken the umbilicus, then cutting off the umbilical cord, weighing the body weight of each piglet, making a record, retracting the umbilical cord into a delivery passage when the sow is delivered, finding the placenta of the corresponding piglet through the mark on the umbilical cord when all the fetal membranes are discharged after the sow delivery is finished, collecting the placenta corresponding to one normal weight (Normal birth weight, NBW, > 1.4 kg) and Low weight (Low birth weight, LBW, < 1.1 kg) of the piglet in each nest, and cutting off 3 placenta molecular samples from the middle and lower 3 parts on the placenta after the amniotic membrane with smooth surface is torn off; 1 part of paraformaldehyde fixed sample is sheared from the middle part of the placenta, and the fixed sample is not squeezable. The molecular sample is packed with tinfoil paper and put into liquid nitrogen for preservation, and the fixed sample is put into a test tube containing paraformaldehyde for preservation at room temperature.

(3) Breast milk sample collection

Collecting the sow colostrum: 8 sows are randomly selected in each group, milk collection is started when the sows give birth to 2-3 piglets, after the piglets arch the breasts of the sows with the heads and make a sound of humming, the sows make a humming sound, the milk is collected in the rapid past, the mammary tissue of the pigs is massaged by hands, milk can be collected by squeezing a mammary duct, 15mL of colostrum is collected from the front, middle and rear 3 nipple parts of the sows, and the colostrum is stored at the temperature of-80 ℃ for standby.

Collecting normal milk of sows: the piglets are transferred to the nursery house on the weaning day, and the sow is still in the delivery room. In the next morning, as no piglets suck milk, the sows can rise seriously, normal milk can be rapidly extracted at the moment, 8 sows are randomly selected from each group, 15mL of normal milk is extracted from front and rear 2 nipples, and the sows are placed at the temperature of-80 ℃ for storage for later use.

3. Measurement index and method

(1) Serum iron, milk iron and placenta iron content determination

According to the manufacturer's instructions, serum iron kit (product number: A039-1-1, nanjing institute of biological engineering, nanjing) was used to determine the iron content of the serum and cord blood of the sow and the piglet; measuring iron content in colostrum and normal milk by using tissue iron kit (product number: A039-2-1, nanjing institute of biological engineering, nanjing); placenta iron content was determined using a commercial ferrozine colorimetric assay kit (cat# ADS-F-D007, jiangsu Adio Biotech Co., ltd., jiangsu).

(2) Detection of total iron binding force, ferritin, transferrin, lactoferrin content

The total iron binding force of the serum of the sow and the piglet is detected by using a commercial kit (goods number: A040-1-1, nanjing institute of biological engineering, nanjing); serum and lactoferrin, serum transferrin and lactoferrin were each detected using the corresponding pig ELISA kit (accession numbers MM-77617O1, MM-32623O1 and MM-77794O1, enzyme-linked, jiangsu) and the assay was performed according to the instructions. Iron saturation = serum iron/total iron binding force x 100%; serum unsaturated iron binding (μmol/L) =total iron binding-serum iron.

(4) Detection of hemoglobin, number of red blood cells, hematocrit and the like in sow blood

Whole blood hemoglobin, red blood cell count and packed red blood cell volume of the sow and the piglet are detected by a full-automatic blood analyzer. The whole blood hemoglobin of the sow is also detected by using a pig blood hemoglobin ELISA kit (product number: MM-78033O1, enzyme-linked immunosorbent assay, jiangsu) and the step method is carried out according to the kit instruction developed by Jiangsu enzyme-linked biosystems.

(5) Determination of placental vascular density

HE staining, procedure was performed according to the instructions of the hubei baiao biotechnology company.

(6) Detection of mRNA expression level of placenta iron metabolic pathway

Collecting placentaRNA is extracted in a molecular sample and is reversely transcribed to obtain cDNA, and then q-PCR test is carried out according to a conventional method to detect the expression difference of placenta iron metabolism related genes (Fn, TF, TFR1, TFR2, DMT1, ZIP14, FPN), angiogenesis related genes (BFG, CD 31) and inflammation related genes (CSF 3, IL-1 beta, HIF-1 alpha, TNF-alpha, IL-6, TGF-beta, IL-10). The amplification primers are designed by using a Primer 6, the primers are verified by using Blast in NCBI, and then the primers are synthesized by Guangzhou synthesis of biological engineering Co., ltd, and fluorescent quantitative PCR test is carried out after the optimal annealing temperature is searched by common PCR and the product uniqueness is verified. Using 384 well quantitative PCR plates, the reaction system was: 2. Mu.L cDNA, 5. Mu.L 2X Color SYBR Green qPCR Master Mix, 0.2. Mu.L upstream and downstream primers, 2.6. Mu.L sterile H ₂ O. The reaction procedure is: 95 ℃ for 5min;95℃for 10sec and 60℃for 30sec for 40 cycles. Based on the threshold cycle (Ct) of the target gene and the reference, 2 was used ^-ΔΔCt The relative expression level of mRNA of each target gene in the sample is calculated by the method, and 18S rRNA is used as an internal reference gene.

(7) Detection of protein expression level of placenta iron metabolic pathway

And carrying out Western Blot test on the collected and stored placenta molecular samples, and detecting the expression levels of the key proteins TF and TFR1 of the iron metabolic pathway. Beta-actin (4970) and Anti-rabit IgG (7074) antibodies were purchased from Cell Signaling Technology company (united states); transferrin (A19130), ATPB (A11214), UQRC 1 (A3339), SDHA (A13852) and NDUFB8 (19732) antibodies were purchased from Eboltag Biotechnology Inc. of Wuhan; transferrin Receptor 1 (10084-2-AP) antibody was purchased from Proteintech (USA).

4. Data statistics and analysis

After the test data are preliminarily consolidated by Excel 2010 software, the data are subjected to single-factor analysis of variance by adopting Spass software. The normalization test of all data was performed using the Kolmogorov-Smirnov test and the variance alignment test was performed using the level's test. Duncan's method multiple comparisons were performed for those with significant differences. The results are expressed by mean value + -standard error, P.ltoreq.0.05 and the superscript of the different letters each indicate significant differences, while 0.05 < P < 0.10 indicates trending, and P > 0.10 indicates no differences between groups. The mapping was done using GraphPad Prism 8.0 software.

5. Results

(1) The effect of adding different levels of protein iron in the feed of the sow on the iron content and the lactoferrin content in serum, milk and placenta is shown in figure 2, wherein A is the serum iron content of the sow during delivery, B is the serum iron content of weaned pigs, C is the serum iron content of umbilical cord blood, D is the placenta iron content, E is the colostrum iron content, F is the normal-milk iron content, G is the colostrum lactoferrin content, and H is the normal-milk lactoferrin content; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=8. As shown in fig. 2, compared with the L-irongroup, the M-irongroup significantly increased serum Iron (P < 0.01), cord blood serum Iron (P < 0.05), colostrum Iron (P < 0.05) and normal-milk Iron content (P < 0.01) in the sow and had a tendency to increase the lactoferrin content in normal milk (p=0.09); the H-photon group remarkably improves the contents of piglet serum Iron (P is less than 0.05) and sow normal-milk Iron (P is less than 0.05), and has the trend of improving the contents of farrowing sow serum Iron (P=0.08), umbilical cord blood serum Iron (P=0.09) and colostrum Iron (P=0.06).

(2) The influence of the addition of different levels of protein iron to the serum physiological index of the sow fed diet is shown in a figure 3, wherein A is the content of the serum ferritin produced by the sow, B is the content of the transferrin produced by the sow, C is the TIBC (total iron binding capacity) produced by the sow, D is the UIBC (unsaturated iron binding capacity) produced by the sow, E is the iron saturation of the serum produced by the sow, F is the content of the ferritin produced by the piglet, G is the content of the transferrin produced by the piglet, H is the TIBC produced by the piglet, I is the UIBC produced by the piglet and J is the iron saturation of the piglet; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=8. As can be seen from FIG. 3, compared with the L-irongroup, the other two groups reduce the serum TIBC of the weaned piglets (P < 0.01), and remarkably improve the serum Iron saturation of the weaned piglets (P < 0.05), and the M-irongroup remarkably improves the serum transferrin content of the sows (P < 0.01). In addition, the M-photon group remarkably improves the serum Iron saturation of the sow (P is less than 0.05) compared with the other two groups, the H-photon group remarkably improves the serum transferrin content of the piglet (P is less than 0.01), and the method has the tendency of improving the serum ferritin of the sow (P=0.09) and reducing the serum TIBC of the piglet (P=0.08).

(3) The influence of the addition of different levels of protein iron to the blood biochemical index of the sow and the piglet is shown in a figure 4, wherein A is the content of the whole blood RBC (red blood cells) of the sow, B is the content of the whole blood HGB (hemoglobin) of the sow, C is the level of the whole blood HGB of the umbilical cord, D is the content of the whole blood WBC (white blood cells) of the sow, and E is the content of the whole blood PLT (platelets) of the sow; f is the content of weaned pig whole blood RBC, G is the content of weaned pig whole blood HGB, H is the content of weaned pig whole blood WBC, and I is the content of weaned pig whole blood PLT; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=8. As can be seen from FIG. 4, the remaining two groups increased the HGB level of sow (P < 0.01) compared with the L-photon group, the H-photon group also significantly increased the HGB level of umbilical cord blood (P < 0.05), and the M-photon group had a tendency to increase the RBC number of sow (P=0.10). In addition, the number of the PLT of the sow in the M-photon group is obviously reduced (P < 0.05) compared with that in the L-photon group (P < 0.01) and the H-photon group, and the H-photon group has the tendency of increasing the PLT number of weaned pigs (P=0.08). This suggests that the addition of moderate levels of protein iron to sow diets improves the inflammatory response of the farrowing sows, while the supplementation of high levels of iron with maternal iron instead increases the inflammatory response of piglets.

(4) The influence of different levels of protein iron added into sow diet on the iron transfer of placenta is shown in figure 5, wherein A is the mRNA expression level of iron metabolism related genes in the placenta of each group of sows, and B is the protein expression level of iron metabolism key factors TF and TFR 1; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=6-8. As can be seen from FIG. 5, the H-photon group significantly increased the mRNA expression levels of Fn and TFR2 and decreased the mRNA expression of DMT1 (P < 0.05) compared to the M-photon group. Compared with the other two groups, the mRNA and protein expression amounts of TF and TFR1 in the placenta of the M-irongroup sow are obviously up-regulated (P is less than 0.05), which indicates that the Iron content of the maternal flowing to the fetus can be increased by adding medium-level protein Iron into the diet of the sow.

(5) To explore the effect of different levels of protein iron added into sow feed on the expression and mitochondrial function of placenta inflammatory factors, the invention firstly detects the mRNA expression levels of pro-inflammatory factors CSF3, IL-1 beta, HIF-1 alpha, TNF-alpha, IL-6 and anti-inflammatory factors TGF-beta and IL-10 in pig placenta in different groups, as shown in figures 6A-6G; wherein, A-E is the mRNA expression quantity of pro-inflammatory factors CSF3 (A), IL-1 beta (B), HIF-1 alpha (C), TNF-alpha (D) and IL-6 (E) in each group of pig placenta; F-G is the mRNA expression level of anti-inflammatory factors TGF-beta (F) and IL-10 (G) in each group of pig placenta; h is the protein expression level of mitochondrial complexes SDHA, ATPB, UQCRC, NDUFB 8; l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=7-8. As can be seen from fig. 6, the expression of HIF- α was decreased in the placenta of the pig in the M-irongroup compared with that in the L-irongroup (p=0.10); compared with the H-irongroup, the expression level of TNF-alpha is obviously reduced (P is less than 0.01), the expression level of IL-6 is more reduced (P=0.07), the expression level of IL-10 is increased (P=0.10), and the expression level of TGF-beta is obviously up-regulated (P is less than 0.05) compared with the other two groups. Then the test detects the protein expression level of the mitochondrial complexes SDHA, ATPB, UQCRC and NDUFB8, and the results show that compared with the M-photon group, the protein expression levels of ATPB and SDHA of the pig placenta of the H-photon group are obviously reduced (P < 0.05), and the protein expression levels of the NDUFB8 of the L-photon group and the H-photon group are obviously reduced (P < 0.05) compared with the M-photon group. It is shown that the addition of moderate levels of protein iron to sow feed increases the anti-inflammatory capacity of the placenta, whereas high-iron may cause oxidative stress by damaging the placenta mitochondrial complex, causing damage to the placenta.

(6) In order to explore the influence of different levels of protein iron added into sow feed on placenta vascular functions, the invention firstly detects the expression of placenta angiogenesis genes, and detects the vascular density of high and low weight placenta by utilizing placenta HE staining, as shown in figure 7, wherein A-B is the mRNA expression quantity of placenta angiogenesis related genes BFGF (A) and CD31 (B); c is LBW and NBW placental vascular density statistics and representative field of view under 40-fold microscopy; LBW (Low birth weight, < 1.1kg for Low weight piglets); NBW (Normal birth weight, > 1.4kg for normal weight piglets); l-photon: a low level iron group; m-photon: a horizontal iron group; H-Iron: a high-level iron group; n=6. As can be seen from FIG. 7, BFGF expression level was significantly increased (P < 0.05) in NBW placenta of the M-irongroup sow as compared with the other two groups. In addition, CD31 expression in NBW placenta of M-irongroup sow was significantly increased (P < 0.05) compared with L-irongroup sow. Compared with the other two groups, the M-irony group has obviously increased placenta vascular density (P < 0.05) in high and low body weight. It shows that the addition of medium level protein iron to sow feed can improve placenta vascular function.

The above results indicate that:

(1) Compared with the L-photon group, the sow stillbirth rate and the ineffective piglet rate of the M-photon group are obviously reduced, and the mummy number of the sow stillbirth rate is 0;

(2) Compared with the L-photon group, the average daily gain of the suckling piglets tends to be improved;

(3) Compared with the L-photon group, the primary piglet hair color of the M-photon group is obviously improved;

(4) Compared with the L-photon group, the serum Iron saturation of the sow and the umbilical cord of the sow in the M-photon group, the serum Iron saturation of the sow and the hemoglobin level of the sow are obviously improved, compared with the M-photon group, the serum Iron saturation of the sow delivered in the H-photon group is obviously reduced, and the platelet number is obviously increased;

(5) Compared with the L-irongroup, the M-irongroup has the advantages that the milk Iron is obviously improved, and the normal milk lactoferrin has an improved trend;

(6) Compared with the other two groups, the expression levels of placenta TF, TFR1, BFG, CD31 and TGF-beta in the M-photon group are obviously up-regulated, and the expression levels of HIF-alpha, TNF-alpha and IL-6 are reduced; HE staining results show that the placenta vascular density of the M-photon group is obviously improved; compared with the M-photon group, the H-photon group obviously regulates the mRNA expression quantity of placenta Fn and TFR2, reduces the mRNA expression quantity of DMT1 and the protein expression quantity of ATPB and SDHA.

According to the invention, firstly, the influence of different levels of protein iron on the reproductive performance of the sow and the growth performance of the piglet is explored by adding the protein iron into the sow feed, and the sow feed is found that the reproductive performance of the sow and the growth performance of the piglet can be improved by adding 0.13% of protein iron (200 ppm based on iron element), the dead birth rate and the ineffective piglet rate of the sow are obviously reduced, the mummy number of the sow in the lactation period of the sow is 0, the average daily feed intake of the sow is obviously improved, and the average daily weight gain of the suckling piglet is tended to be improved. Meanwhile, the contrast of the hair color of the newborn piglet shows that the addition of 0.13% of protein iron (200 ppm calculated by iron element) into the sow feed can promote the red hair brightness of the newborn piglet skin. On the basis, the invention further discusses the influence of different levels of protein iron added into the sow feed on the iron nutrition level and the transmission efficiency of the sow and further discovers that the supplementation of 0.13% of protein iron (200 ppm calculated by iron element) not only can improve the iron nutrition level of the sow and the transmission efficiency of the mother body through blood, placenta and milk. Finally, the invention focuses on placenta tissue, and elucidates the influence and action mechanism of different levels of iron on placenta function. As a result, it was found that the mechanism may be: either iron deficiency or high-dose iron induces placental inflammatory responses, and high-dose iron induces oxidative stress by damaging the placental mitochondrial complex, resulting in insufficient placental angiogenesis, increasing the occurrence of dead fetus and mummy. The sow feed is added with 0.13% of protein iron (200 ppm calculated by iron element), so that the performance of the sow and the placenta function of the sow can be improved, the iron nutrition level of the sow and the transmission efficiency of the maternal iron are improved, and the iron storage of the sow is increased, so that the occurrence of the invalid piglet rate of the sow is reduced, and the red hair and the bright of the primary piglet skin are promoted. The research result can provide theoretical basis and technical support for improving the IDA of the sow and improving the performance of the sow and the piglet by applying the novel iron supplement in the sow production.

In conclusion, the sow feed is added with 0.13% of protein iron (200 ppm calculated by iron element), so that the performance of a sow and the placenta function of the sow can be improved, the iron nutrition level of the sow and the transmission efficiency of mother source iron are improved, and the storage of fetal pig iron is increased, so that the occurrence of invalid piglet rate of the sow is reduced, and the red hair and the bright hair of primary piglet skin are promoted.

The protein iron added into the sow feed has the advantages of good chemical stability, high biological potency and easy digestion and absorption, the biological potency is higher, the utilization rate of the protein iron is 1.85 times of that of ferrous sulfate, and the protein iron is an ideal novel feed iron supplement. In sow production, the iron requirement of the sow recommended by NRC is 80ppm, but iron cannot freely pass through the placenta due to the placenta barrier, and the iron nutrition transmission of the sow is reduced, so that the iron supplement of the sow in production is often used far higher than the recommended iron requirement of NRC. The national institute of agriculture, the state of the people's republic of China bulletin No. 2625-the feed additive safety use codes clearly state that the maximum limit for adding iron to sow ration is 750ppm (in terms of iron). If the iron content exceeds 750ppm, the excessive use of iron is considered to adversely affect the growth performance of animals. The invention screens and determines the proper level of the iron additive (0.13% of protein iron, 200ppm calculated by iron element) through a series of experiments to improve the iron nutrition level and the iron transfer efficiency of the sow and the piglet, and has important practical significance for improving the reproductive performance of the sow and the growth performance of the piglet.

The above embodiments are only illustrative of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention, and various modifications and improvements made by those skilled in the art to the technical solutions of the present invention should fall within the protection scope defined by the claims of the present invention without departing from the design spirit of the present invention.

Claims (10)

1. The sow feed for reducing the invalid piglet rate and promoting the red hair brightness of the newborn piglet skin is characterized by comprising the following raw materials in percentage by mass: 99.73-100% of basic ration, 0-0.27% of protein iron, and the protein iron is not 0.

2. The sow feed for reducing the rate of ineffective piglets and promoting the red hair brightness of pigskin of newborn piglets according to claim 1, wherein the raw materials of the basic ration comprise the following components: corn, wheat bran, soybean hulls, soybean meal, salt, stone dust, calcium bicarbonate, soybean oil, choline, baking soda, lysine, threonine, tryptophan, valine, glucose, fish meal, a mildew preventive, an antioxidant, phytase, fermented soybean meal and premix.

3. The sow feed for reducing the rate of ineffective piglets and promoting the red hair and brightness of pigskin of newborn piglets according to claim 1, wherein the raw materials comprise the following components in percentage by mass:

4. A sow feed as claimed in any one of claims 1 to 3 in which the iron content of the protein iron is 15wt.% to reduce the rate of ineffective piglets and promote the red hair lightening of the pigskin of the newborn piglets.

5. The sow feed for reducing the rate of ineffective piglets and promoting the red hair brightness of pigskin of newborn piglets according to claim 2, wherein the premix comprises the following components: iron, zinc, copper, manganese, iodine, selenium, cobalt, vitamin A, vitamin D3, vitamin E, vitamin K3, vitamin B1, vitamin B2, vitamin B6, vitamin B12, nicotinamide, calcium pantothenate, folic acid, biotin, L-ascorbic acid C, and 25-hydroxycholecalcia.

6. Sow feed for reducing the rate of ineffective piglets and promoting the red hair brightness of pigskin of newborn piglets according to claim 2, wherein the premix in 1kg of basic ration comprises the following components: 5000IU of vitamin A, 3500IU of vitamin D, 15mg of vitamin E, 31.2mg of vitamin K, 11mg of vitamin B, 25mg of vitamin B, 62.5mg of vitamin B, 120.01mg of vitamin B, 10mg of nicotinamide, 4mg of calcium pantothenate, 1.12mg of folic acid, 0.24mg of biotin, 50mg of L-ascorbic acid, 17.5 mug of 25-hydroxycholecalcia, 154mg of iron, 100mg of zinc, 22mg of copper, 50mg of manganese, 0.56mg of iodine, 0.5mg of selenium and 0.56mg of cobalt; wherein the iron is derived from inorganic iron.

7. A method for preparing sow feed for reducing ineffective piglets as claimed in any one of claims 1-6, promoting red hair and bright pigskin of newborn piglets, comprising the steps of: and weighing the raw materials of the components according to a proportion, and uniformly mixing to obtain the sow feed for reducing the invalid piglet rate and promoting the red hair brightness of the newborn piglet skin.

8. Use of a sow feed as claimed in any one of claims 1 to 6 for reducing the rate of ineffective piglets and for promoting the red hair and bright skin of newborn piglets for improving reproductive performance and growth performance of piglets.

9. A method for feeding a sow in a period from a late gestation period to a lactation period, comprising the following steps:

(1) The daily feed feeding amount of each sow is 2.5kg after 85-90 days after mating;

(2) The daily feed feeding amount of each sow is 3.0kg 91-95 days after the breeding;

(3) 96-107 days after mating, the daily feed feeding amount of each sow is 3.5kg;

(4) 108 days after mating-delivery, wherein the daily feed intake of each sow is 0-3.5kg;

(5) 1 to 6 days after delivery, the daily feed feeding amount of each sow is 1.0kg in 1 day after delivery, and 1.0kg is added in 2 to 6 days after delivery;

(6) The daily feed feeding amount of each sow is free feeding after 7-21 days after delivery;

The feed is a sow feed for reducing the rate of ineffective piglets and promoting the red hair brightness of pigskin of newborn piglets according to any one of claims 1 to 6.

10. The method of claim 9 wherein the sow is a growing binary multiparous sow.