CN104155418A - Method for measuring corn poultry metabolizable energy through in-vitro enzyme digestion - Google Patents

Abstract

The invention relates to a method for measuring corn poultry metabolizable energy through in-vitro enzyme digestion. The method includes following steps: digesting corn in vitro through a two-step enzymic method (pepsin-pancreatin), and carrying out regression analysis of an in-vitro dry matter disappearance rate (DMD) and a crude protein disappearance rate (CPD) of the corn to a poultry metabolizable energy of the corn for establishing a mathematic model of the in-vitro dry matter disappearance rate (DMD) and the crude protein disappearance rate (CPD) of the corn to the poultry metabolizable energy. The method can be used for quickly evaluating the poultry metabolizable energy of the corn. The method can allow the poultry metabolizable energy of the corn to be evaluated quickly, is suitable for production application and can provide guarantee for preparing a poultry daily ration more accuraterly.

Description

A kind of method of utilizing vitro enzyme digestion method to measure corn poultry metabolizable energy

(1) technical field

The present invention relates to a kind of method of utilizing external two step enzyme digestion evaluation corn poultry metabolizable energies, belong to field of feed.

(2) background technology

Energy feed is the important component part of feed, and fodder energy level determines the performance of feed intake and the normal production performance of animal.Corn is the topmost energy feed using during China's animal and fowl fodder is produced, and its effective energy value is the principal element of restriction feed efficiency.But, in actual Feed Manufacturing, corn effective energy value (metabolizable energy of such as poultry) as the leading indicator of weighing its feeding value but because of measure required time long, to many reasons such as having relatively high expectations of instrument, except specializing in, substantially cannot measure, can only carry out formula Design according to the metabolizable energy value of demarcating in feed ingredient database.And the significant correlations such as the metabolizable energy of corn and its kind, planting area, processing mode have larger range of variation, in production, carry out formula Design according to fixed value in database, be easy to cause energy surplus or deficiency in institute's formula feed, cause production loss.Therefore, the metabolizable energy value of accurately evaluating corn is the key of reasonable preparation poultry feed, is the basis of the reasonable utilization of energy feed, and production efficiency, saving feed resource to raising poultry are significant.

(3) summary of the invention

In order to address the above problem, the invention provides a kind of method of utilizing vitro enzyme digestion method to measure corn poultry metabolizable energy; Object is: provide a kind of by vitro enzyme digestion method rapid evaluation corn poultry metabolizable energy and be suitable for the method for production application, can provide safeguard for preparing more accurately poultry diet.

The present invention is by two step enzyme methods (pepsin-pancreatin) external digestion corn, carry out the regretional analysis of the outer dry disappearance rate (DMD) of Corn, crude protein disappearance rate (CPD) and its poultry metabolizable energy, set up the mathematical model of the outer dry disappearance rate of Corn, crude protein disappearance rate and poultry metabolizable energy, can be for the poultry metabolizable energy of rapid evaluation corn.Corn poultry metabolizable energy (AME) the estimation mathematical model of setting up is as follows:

AME(kcal/kg)＝4122.24－1591.43×DMD+365.70×CPD

Utilize vitro enzyme digestion method to measure a method for corn poultry metabolizable energy, comprise the following steps:

1, corn sample is pulverized, and crosses 40～60 mesh sieves, and 105 ± 2 DEG C dry to constant weight, and measures the front crude protein content (CP of corn external digestion by GB/T 6432 methods ₀); Accurately take and pulverize rear corn sample 1.0g (M ₀, be accurate to 0.0001g), adding concentration is 1.0mg/mL pepsin aqueous solution 10～15mL (pH=1.5～3.5), sealing, 35～42 DEG C of constant temperature water bath vibrations (100～180r/min) digestion 4 hours; In corn sample by above-mentioned digestion after 4 hours, adding concentration is 1.0mol/L NaOH solution 0.1～0.5ml neutralization; Be 2.5mg/mL trypsase aqueous solution 10～15mL to adding concentration in the corn sample after above-mentioned neutralization, after mixing, transfer in the bag filter of 12000～14000D and seal; Bag filter is put into 300～500mL phosphate buffer (pH=6.5～9.0), 35～42 DEG C of constant temperature water bath vibrations (100～180r/min) digestion 20 hours; Take out bag filter, repeatedly rinse slaking residue in bag filter with distilled water, 105 ± 2 DEG C dry to constant weight residue, accurately take the quality (M of the residue that dries to constant weight ₁), and by GB/T 6432 methods measure residues crude protein content (be crude protein content after corn external digestion, CP ₁); Calculate respectively external dry disappearance rate (DMD) and the crude protein disappearance rate (CPD) of corn by following formula:

$\mathrm{DMD}=\frac{M_0\left(g\right)-M_1\left(g\right)}{M_0\left(g\right)}$

Wherein, DMD is corn dry disappearance rate;

M ₀for the quality before corn external digestion, the g of unit;

M ₁for the outer postdigestive quality of Corn, the g of unit;

$\mathrm{CPD}=\frac{C{P}_0(\%)-C{P}_1(\%)}{C{P}_0(\%)}$

Wherein, CPD is From The Corn Protein disappearance rate;

CP ₀for crude protein content before corn external digestion;

CP ₁for crude protein content after corn external digestion.

2, need are measured to external dry disappearance rate (DMD) and crude protein disappearance rate (CPD) substitution mathematical model AME (kcal/kg)=4122.24-1591.43 × DMD+365.70 × CPD of corn sample, drawn the poultry metabolizable energy of corn.

Result of use of the present invention is: as a kind of method of evaluating corn poultry metabolizable energy, be applicable to the Fast Measurement of corn metabolizable energy value in producing, can effectively improve the accuracy that feed formula calculates, improve capacity usage ratio, save feed resource.

(3) embodiment

Embodiment 1

1, gather 5 corn samples, be numbered respectively 1,2,3,4 and No. 5; Measure respectively external dry disappearance rate (DMD) and the crude protein disappearance rate (CPD) of each corn sample according to method of the present invention, in mathematical model AME (kcal/kg)=4122.24-1591.43 × DMD+365.70 × CPD that measured result substitution is built, obtain the assessed value (table 1) of corn metabolizable energy.

For the degree of agreement of checking assessed value and corn metabolizable energy actual value, measure in accordance with the following methods the measured value of five kinds of corn metabolizable energies: with the blue brown cock in adult sea healthy, body weight is close, being placed in the indoor single cage list of ring control metabolic determination only raises, house temperature is 24 DEG C ± 3 DEG C, intensity of illumination 20LX, every day, light application time was 16h.In the non-test phase, feed and can meet the full price ration formulation of cock physiological requirements, freely drink water and search for food.Before on-test, test chicken is divided into 5 groups (measuring respectively 5 corn samples) at random, every group of 4 repetitions, 3 of each repetitions, normally feed and adapt to after 7 days, test chicken fasting, freely drink water, continuous emptying 32 hours, raise by force afterwards the corn sample that 40g pulverizes, collect continuously the excreta of 32 hours.Respectively analytical unit quality corn sample and corresponding excremental can value, the difference of the two is the measured value (table 1) of corn metabolizable energy.

2. test findings

Test findings shows, corn metabolizable energy assessed value and measured value difference are less, and the variation amplitude of 5 samples is 0.17%～1.70%, and the measurement result of Evaluation model is (table 1) accurately.

Table 1 corn sample metabolizable energy measured value and assessed value contrast (kcal/kg)

Embodiment 2

1. be the practicality of the constructed assessment method of checking the present invention, and with produce in the method for carrying out feed formulation with corn metabolizable energy value in database that generally adopts compare, test as follows.

Gather 2 of corn samples, be labeled as respectively 1# and 2#; Use respectively method of the present invention to carry out the mensuration of metabolizable energy these 2 corn samples, and prepare meat-chicken complete feedstuff with the metabolizable energy value of evaluation and test daily ration as test group, be labeled as respectively evaluation 1# and evaluation 2#, use 1# and 2# corn sample to test as a control group daily ration according to the data preparation broiler fodder of corn metabolizable energy value in Chinese feed ingredient and nutritive value table (2010), be labeled as respectively contrast 1# and contrast 2#.

576 of 1 age in days AA meat chicks for test, ground bedding and padding are flat supports, and is divided at random 4 groups, the evaluation 1# that feeds respectively, evaluation 2#, contrast 1# and contrast 2# test daily ration, every group of 3 repetitions, 48 of each repetitions.Feed by prepared daily ration grouping, free choice feeding and drinking-water, illumination in 24 hours.42 days experimental periods.Relatively according to the impact of numerical value formula feed on meat chicken production performance and Slaughter in corn metabolizable energy assessed value and database.

2. test findings

Test findings (in table 2 and table 3) shows, utilize the corn metabolizable energy value of the mathematical model evaluation building, with using the data formula feed in feed ingredient and nutritive value table, broiler chicken is delivered for sale to body weight, average daily ingestion amount, average daily gain is all without significant impact (P>0.05), but the former material anharmonic ratio is all lower than the latter, especially 2# corn sample significantly reduces (1.84VS1.70, P=0.019), show to utilize corn metabolizable energy assessed value that the inventive method calculates can effectively improve the transformation efficiency of feed compared with usage data storehouse numerical value preparation broiler fodder, reduce feed waste, reduce aquaculture cost.Presentation of results, the mathematical model that this method builds is applicable to the rapid evaluation of corn metabolizable energy value in production, and can better ensure the accuracy of feed formulation, ensures the performance of meat chicken production performance.

The impact of table 2 1# corn sample on meat chick production performance

The impact of table 3 2# corn sample on meat chick production performance

Note: ^a,bwith the different significant differences (P<0.05) that represent of a line acceptance of the bid note.

Claims (1)

1. utilize vitro enzyme digestion method to measure a method for corn poultry metabolizable energy, it is characterized in that comprising the following steps:

1) corn sample is pulverized, and crosses 40～60 mesh sieves, and 105 ± 2 DEG C dry to constant weight, and measures the front crude protein content CP of corn external digestion by GB/T 6432 methods ₀; Accurately take and pulverize rear corn sample M ₀1.0g, adding concentration is the pepsin aqueous solution 10～15mL of 1.0mg/mL pH=1.5～3.5, sealing, 35～42 DEG C of constant temperature water bath vibration 100～180r/min digestion 4 hours; In corn sample by above-mentioned digestion after 4 hours, adding concentration is 1.0mol/L NaOH solution 0.1～0.5ml neutralization; Be 2.5mg/mL trypsase aqueous solution 10～15mL to adding concentration in the corn sample after above-mentioned neutralization, after mixing, transfer in the bag filter of 12000～14000D and seal; Bag filter is put into the phosphate buffer of 300～500mL pH=6.5～9.0,35～42 DEG C of constant temperature water bath vibration 100～180r/min digestion 20 hours; Take out bag filter, repeatedly rinse slaking residue in bag filter with distilled water, 105 ± 2 DEG C dry to constant weight residue, accurately take the mass M of the residue that dries to constant weight ₁, and to measure the crude protein content of residues by GB/T 6432 methods be crude protein content CP after corn external digestion ₁; Calculate respectively external dry disappearance rate DMD and the crude protein disappearance rate CPD of corn by following formula:

$\mathrm{DMD}=\frac{M_0\left(g\right)-M_1\left(g\right)}{M_0\left(g\right)}$

Wherein, DMD is corn dry disappearance rate;

M ₀for the quality before corn external digestion, the g of unit;

M ₁for the outer postdigestive quality of Corn, the g of unit;

$\mathrm{CPD}=\frac{C{P}_0(\%)-C{P}_1(\%)}{C{P}_0(\%)}$

Wherein, CPD is From The Corn Protein disappearance rate;

CP ₀for crude protein content before corn external digestion;

CP ₁for crude protein content after corn external digestion;

2) need are measured to external dry disappearance rate DMD and crude protein disappearance rate CPD substitution mathematical model AME (kcal/kg)=4122.24-1591.43 × DMD+365.70 × CPD of corn sample, drawn the poultry metabolizable energy of corn.