CN115316537A

CN115316537A - Pig feed and application thereof in pig body fat regulation

Info

Publication number: CN115316537A
Application number: CN202211031520.XA
Authority: CN
Inventors: 单体中; 王力仪; 张舒; 汪以真
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 2022-08-26
Filing date: 2022-08-26
Publication date: 2022-11-11

Abstract

The invention provides a pig feed and application thereof in pig body fat regulation, and belongs to the technical field of feeds. The invention combines 60-70 parts of corn, 15-20 parts of bean pulp, 5-10 parts of bran and 0.8-5 parts of conjugated linoleic acid, overcomes the problems of complex components and poor effect of the feed for regulating and controlling the meat quality in the prior art, can obviously reduce the pig backfat thickness and obviously improve the intramuscular fat content, has important significance for improving the pork quality and producing high-quality and safe high-end pork.

Description

Pig feed and application thereof in pig body fat regulation

Technical Field

The invention relates to the technical field of feed, in particular to pig feed and application thereof in pig body fat regulation.

Background

China is the largest meat producing country and consuming country in the world, pork is the most important animal-derived food for consumers, and the production of high-quality pork and the stable market supply are related to the mass of people. With the increasing living standard of people, people are pursuing high-quality high-end pork, and the requirement on the quality of the pork is higher and higher. Quality issues and healthy production of pork have become a focus of national and consumer concern. Therefore, how to produce high-quality, safe and high-end pork while ensuring the pork yield becomes one of the key problems which need to be solved urgently in long-term development of the live pig industry. In pig production, fat deposition and muscle development are key factors affecting pork quality. Fat deposition directly affects the growth and meat production performance of pigs. Wherein, the backfat thickness can reflect the fat deposition capability of the pig, and has strong negative correlation with the lean meat percentage of the carcass, and the deposition directly influences the lean meat percentage of the pig carcass. Furthermore, fat deposition in skeletal muscle, especially muscle fat (IMF) deposition, is closely related to pork quality and nutritional value, and its content is directly related to flesh color, flavor, juiciness and tenderness of meat. The variety and nutrition are main methods for regulating and controlling fat deposition of pork, but the existing feed capable of regulating and controlling meat quality is complex in components and poor in effect, and cannot meet industrial requirements.

Disclosure of Invention

The invention aims to provide a pig feed and application thereof in pig body fat regulation so as to solve the problems that the feed for regulating and controlling meat quality in the prior art is complex in components and poor in effect.

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

the invention provides a pig feed which comprises the following components in parts by weight:

60 to 70 portions of corn, 15 to 20 portions of bean pulp, 5 to 10 portions of bran and 0.8 to 5 portions of conjugated linoleic acid.

Preferably, the conjugated linoleic acid is a mixture of the isomers t10, c12-CLA and c9, t 11-CLA.

Preferably, the mass ratio of the isomer t10, c12-CLA to the isomer c9, t11-CLA is 1.

Preferably, the components further comprise a feed additive premix.

The invention also provides application of the pig feed in regulation of pig body fat.

Preferably, the body fat regulation is reduction of pig backfat thickness and increase of intramuscular fat content.

Preferably, the feeding is carried out 21 to 56 days after the fattening period of the pigs.

The invention has the technical effects and advantages that:

according to the invention, the specific components are proportioned, so that the pig feed obviously reduces the back fat thickness of pigs, obviously improves the intramuscular fat content, has an important significance for improving the pork quality and producing high-quality and safe high-end pork.

Drawings

FIG. 1 shows the results of the detection of the form of subcutaneous fat;

FIG. 2 shows visceral fat morphology assay results;

FIG. 3 shows the result of the morphological examination of the longissimus dorsi of pigs;

FIG. 4 shows the result of the lumbar major morphology test;

FIG. 5 shows the results of detecting the mRNA expression levels of the genes involved in fat synthesis (Fabp 4 and Ppar. Gamma.);

FIG. 6 is a backfat thickness measurement;

fig. 7 shows the measurement results of fat content in the longissimus dorsi muscle.

Detailed Description

60 to 70 parts of corn, 15 to 20 parts of bean pulp, 5 to 10 parts of bran and 0.8 to 5 parts of conjugated linoleic acid.

The pig feed component provided by the invention comprises 60-70 parts of corn, wherein the corn is preferably 63-67 parts by weight, and is further preferably 64-66 parts by weight; the corn of the invention is preferably corn seeds, the corn can be in a whole corn or crushed corn state, and the invention has no special requirement on the grain diameter of the corn and can meet the requirement of feeding pigs for food.

The pig feed component provided by the invention comprises 15-20 parts of soybean meal, wherein the weight part of the soybean meal is preferably 15-20 parts, and further preferably 16-19 parts; the soybean meal refers to a byproduct obtained after soybean oil is extracted from soybeans, has no special requirement on the particle size of the soybean meal, and can meet the requirement of feeding pigs.

The components of the pig feed provided by the invention comprise 5-10 parts of bran, wherein the parts by weight of the bran are preferably 5-10 parts, and are further preferably 6-8 parts; the bran of the invention refers to the outermost epidermis of wheat and is a byproduct obtained after the wheat is processed into flour, and the invention has no special requirement on the grain diameter of the bran and can meet the requirement of feeding pigs.

The components of the pig feed provided by the invention comprise 0.8-5 parts of Conjugated linoleic acid, wherein the English name of the Conjugated linoleic acid is Conjunated linoleic acid, which is called CLA for short; the weight portion of the conjugated linoleic acid is preferably 0.8-5, more preferably 0.9-4, and still more preferably 1.5-3.5; the conjugated linoleic acid is preferably a mixture of an isomer t10, c12-CLA and an isomer c9, t 11-CLA; the mass ratio of the isomer t10, c12-CLA to the isomer c9, t11-CLA is preferably 1.

In the invention, the components of the pig feed also preferably comprise a feed additive premix, and the weight part of the feed additive premix is preferably 1 to 5 parts, and further preferably 2 to 4 parts; the invention has no special requirements on the type of the feed additive premix, and the feed additive premix containing vitamins, trace elements and carriers is adopted in the market, and in a specific embodiment of the invention, the feed additive premix is a 4% middle pig compound premix feed of a natural feed, wherein the components are as follows: each kilogram of the vitamin A health food contains 10.0-16.0 ten thousand IU vitamin A acetate and 5.0-12.0 ten thousand IU vitamin D ₃ 900mg of DL-alpha-tocopheryl acetate, 50.0mg of menadione, 40.0mg of thiamine nitrate, 160mg of riboflavin, 50.0mg of pyridoxine hydrochloride, 0.85mg of cyanocobalamin, 30.0mg of folic acid, 520mg of nicotinamide, 280mg of calcium D-pantothenate, 2.0mg of D-biontElement, 210-625mg copper, 1.50X 10 ³ -7.50×10 ³ mg of iron, 700-2.1X 10 ³ mg of manganese, 700-2.0X 10 ³ Zinc (mg), iodine (5.0-15.0 mg), selenium (3.0-9.0 mg), and stone powder (rest).

The invention also provides the application of the pig feed in pig body fat regulation, wherein the pig body fat regulation is preferably to reduce pig back fat thickness and increase intramuscular fat content, the pig feed is preferably fed on 21-56 days after the pig fattening period, the pig feed is preferably fed from 68-106 kg to 83-124 kg of body weight in a slaughtering period according to the body weight, and the average feed intake is 2.46-2.56kg/d per pig.

The technical solutions provided by the present invention are described in detail below with reference to examples, but they should not be construed as limiting the scope of the present invention.

Example 1

68.6 parts of corn, 19 parts of bean pulp, 7.6 parts of bran, 1 part of conjugated linoleic acid and 3.8 parts of feed additive premix are mixed to obtain the pig feed.

Wherein the feed additive premix is a 4% composite premix feed for middle pigs as a natural feed.

Example 2

Mixing 60 parts of corn, 15 parts of bean pulp, 5 parts of bran, 0.2 part of conjugated linoleic acid and 1 part of feed additive premix to obtain the pig feed.

Example 3

70 parts of corn, 20 parts of bean pulp, 10 parts of bran, 5 parts of conjugated linoleic acid and 5 parts of feed additive premix are mixed to obtain the pig feed.

Comparative example 1

68.6 parts of corn, 19 parts of soybean meal, 7.6 parts of bran, 1 part of rapeseed oil and 3.8 parts of feed additive premix are mixed to obtain the pig feed.

Comparative example 2

Mixing 50.1 parts of corn, 25.2 parts of soybean meal, 10 parts of wheat bran, 1 part of conjugated linoleic acid, 3.6 parts of limestone, 1.2 parts of calcium hydrophosphate, 3.6 parts of sodium chloride, 1.5 parts of lysine and 3.8 parts of feed additive premix to obtain the pig feed.

Experimental example 1 preparation of experimental group

The piglets Du-Chang and the Zaozhuang black-cover pigs are fed with the same feed under the same feeding conditions, are randomly divided into 3 groups, and are respectively fed with the feeds of example 1, comparative example 1 and comparative example 2, which are marked as an experimental group A, an experimental group B and an experimental group C.

The pre-feeding period is 5 days, the formal test period is 30 days, the fattening black-capped pigs of the 3 groups are respectively fed with corresponding daily ration from 68kg to 106kg until 95kg to 110kg are slaughtered, the growing-fattening Duchang big pigs of the experimental group A and the experimental group B are respectively fed with corresponding daily ration from 30kg to 97kg until 90kg to 172kg are slaughtered, and the feeding conditions except the feed are the same. In the whole feeding process, a conventional immunization program is executed, and the pigs have no stress reaction caused by diseases, adverse environments and the like. And recording growth indexes in the culture process. After formal feeding for 30 days, 8 black-cap pigs in each group are randomly selected for slaughtering, and relevant indexes are determined.

Experimental example 2 morphological Observation of longissimus dorsi, psoas major, subcutaneous fat and visceral fat tissue

The paraffin section steps are as follows:

1) Material taking: fresh tissue is fixed with fixative for over 24 hr. Taking out the tissue from the fixing solution, flattening the tissue of a target part in a fume hood by using a scalpel, and placing the trimmed tissue and a corresponding label in a dehydration box;

2) Dehydrating and wax dipping: and (5) putting the dehydration box into a dehydration machine to perform dehydration by gradient alcohol in sequence. 75% alcohol 4h,85% alcohol 2h,90% alcohol 2h,95% alcohol 1h, absolute ethyl alcohol I30min, absolute ethyl alcohol II30min, alcohol benzene 5-10min, xylene I5-10min, xylene II5-10min, paraffin I1h melted at 65 ℃, paraffin II1h melted at 65 ℃, paraffin III melted at 65 ℃ 1h;

3) Embedding: embedding the wax-soaked tissue in an embedding machine. Firstly, molten wax is put into an embedding frame, the tissue is taken out from the dehydration box and put into the embedding frame according to the requirements of an embedding surface before the wax is solidified, and a corresponding label is attached. Freezing at-20 deg.C, cooling, solidifying wax, taking out the wax block from the embedding frame, and trimming the wax block;

4) Slicing: and (3) putting the trimmed wax block into a freezing table at the temperature of-20 ℃ for cooling, and then putting the cooled wax block into a paraffin slicer for slicing, wherein the thickness of the wax block is 4 microns. The slices float on a spreading machine at 40 ℃ warm water to flatten the tissues, a glass slide picks up the tissues, and the slices are baked in a 60 ℃ oven. And taking out the roasted product after water roasting, drying and wax roasting, and storing the product at normal temperature for later use.

HE staining procedure was as follows:

1) Paraffin section dewaxing to water: sequentially placing the slices into xylene I20 min-xylene II 20 min-absolute ethyl alcohol I5 min-absolute ethyl alcohol II 5min-75% alcohol 5min, and washing with tap water;

2) Hematoxylin staining: staining the slices in hematoxylin staining solution for 3-5min, washing with tap water, differentiating the differentiation solution, washing with tap water, returning blue to the blue solution, and washing with running water;

3) Eosin staining: the slices are dehydrated for 5min respectively by 85 percent and 95 percent gradient alcohol in sequence and are dyed for 5min in eosin dye solution;

4) Dewatering and sealing: placing the slices in anhydrous ethanol I5 min-anhydrous ethanol II5 min-anhydrous ethanol III 5 min-dimethyl I5 min-xylene II5min for transparency, and sealing with neutral gum;

5) Microscopic examination and image acquisition and analysis.

Among them, the subcutaneous fat morphology is shown in fig. 1, the visceral fat morphology is shown in fig. 2, the longissimus dorsi morphology is shown in fig. 3, and the psoas major morphology is shown in fig. 4.

As can be seen from the graphs 1 to 4, subcutaneous fat cells of black cap pigs fed with the pig feed are obviously reduced, which shows that the feed has the function of regulating and controlling the shape of subcutaneous fat tissues; the visceral fat cells are obviously reduced, which shows that the feed has the function of regulating and controlling the shape of the visceral fat tissues; the intramuscular fat cells are obviously increased, which shows that the feed can improve the content of the fat in the longisimus muscle and the fat in the psoas major muscle of the black-capped pigs.

Experimental example 3 detection of mRNA expression level of gene involved in fat synthesis of longissimus dorsi

Taking the longissimus dorsi sample of the black-capped pig, and extracting the total RNA by a TRIzol method. The method comprises the following steps:

1) Taking out tissue, adding 500 μ LTRIzol reagent, shearing tissue, homogenizing with homogenizer for 2 times, 30s, and standing at room temperature for 15min.

2) Adding 100 μ L of chloroform, vortex oscillating for 15s, and incubating at room temperature for 10min;

3) Centrifuging at 12000rpm for 10min at 4 deg.C;

4) Separating the solution into three layers, carefully sucking the supernatant, transferring into a new DEPC-treated centrifuge tube, adding equal volume of room temperature isopropanol, mixing, and standing for 10min;

5) Centrifuging at 12000rpm for 10min at 4 deg.C to obtain white RNA precipitate on the bottom wall of the tube;

6) Pouring off the supernatant, adding 500 mu L of 75% precooled ethanol, and suspending and washing the RNA precipitate;

7) Centrifuging at 12000rpm for 5min at 4 ℃;

8) Repeating the steps 6 and 7 once;

9) Pouring off the supernatant, carefully sucking off the residual ethanol at the bottom of the tube by using a pipette, opening the centrifuge tube, and drying and precipitating at room temperature for 20min;

10 Dissolve RNA with 20. Mu.L RNase-free water, dissolve RNA with gentle pipetting with a pipette tip;

11 RNase-free water was used as a control, and the concentration and purity of RNA were measured with a spectrophotometer.

Reverse transcription

Determining the concentration of total RNA, carrying out reverse transcription on a sample with satisfactory purity and integrity, and carrying out a reverse transcription system: RNA 1000/. Mu.L, RNase free water (10-RNA). Mu.L, SYBR Mix enzyme 10. Mu.L.

10min at 30 ℃, 60min at 42 ℃ and 15min at 70 ℃, adding 80 mu L of RNase free water after the reaction is finished, and placing the cDNA at-20 ℃ for later use.

QPCR Applied Biosystems StepOnePlus ^TM Real-Time PCR System, using SYBR Green Master Mix (Roche, indianapolis, USA), with 2 ^-ΔΔCT The method analyzes relative change of gene expression, and the reaction system is as follows:

cDNA 4μL

rnasefree water 0.6 mu L

Primer 0.4 μ L:

primer 18S-F (CCCACGGAATCGAGAAGAG, shown in SEQ ID NO. 1);

primer 18S-R (TTGACGGAAGGGCACCA, shown in SEQ ID NO. 2);

primer Fabp4-F (tggaaacttgttctccagtg, shown in SEQ ID No. 3);

primer Fabp4-R (GGTACTTTCTGATCTAATGGTG, shown in SEQ ID NO. 4);

primer Ppar-F (GGCGAGGGCGATCTTGACAG, shown as SEQ ID NO. 5);

primer Ppar-R (GATGCGAATGGCCACCTCTTT, shown as SEQ ID NO. 6),

SYBR Mix enzyme 5. Mu.L.

The test data were subjected to related data statistics and mapping using SPSS 20.0 statistical software and Graphpad, and the results are shown in fig. 5.

As shown in FIG. 5, the pig feed provided by the invention can improve the fat content in the longisimus dorsi muscle of the black-cap pigs by improving the mRNA expression level of the fat synthesis related genes (Fabp 4 and Ppar gamma).

Experimental example 4 measurement of Back fat thickness, intramuscular fat content and flesh color

The back fat thickness, the intramuscular fat content and the flesh color are measured according to the method recorded in the technical specification of the measurement of the pig muscle quality NY/T8212004, the measurement results of the back fat thickness and the intramuscular fat content of the longest muscle of the black-capped pigs are shown in figures 6 to 7, the data adopt meta analysis, and the measurement results of the fat content and the flesh color of the long and large muscles of the Du pigs are shown in the following table 1:

TABLE 1 Effect on the fat content and flesh color in the longissimus dorsi of Duchen pigs

¹ L, luminance; a, red; b, yellowness.

² And (4) sample size.

³ WMD, weighted average; CI, confidence interval.

The results show that the pig feed provided by the invention can reduce the back fat thickness of the black-capped pigs, improve the content of the longest intramuscular fat of the backs of the Ducheng pigs, obviously reduce the b value of the meat color and better exert the effect of conjugated linoleic acid.

The embodiment proves that the pig feed provided by the invention can obviously reduce the back fat thickness of pigs and obviously improve the content of intramuscular fat, and has important significance for improving the quality of pork and producing high-quality safe high-end pork.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The pig feed is characterized by comprising the following components in parts by weight:

2. The swine feed of claim 1 wherein the conjugated linoleic acid is a mixture of isomers t10, c12-CLA and isomers c9, t 11-CLA.

3. The pig feed according to claim 2, characterized in that the mass ratio of the isomer t10, c12-CLA to the isomer c9, t11-CLA is 1.

4. The pig feed according to claim 1, characterized in that the components further comprise 1 to 5 parts of a feed additive premix.

5. Use of the pig feed according to any one of claims 1 to 4 for the regulation of pig body fat.

6. The use of the pig feed according to claim 5 for body fat modulation in pigs, wherein the body fat modulation is reduction of pig backfat thickness and increase of intramuscular fat content.

7. The use of the pig feed according to claim 6 for the regulation of pig body fat, characterized in that the feeding is carried out 21 to 56 days after the fattening period of the pig.